Support backend for console. To enable console backend, just make
console_size be greater than 0 and a multiple of 4096.
Signed-off-by: WeiXiong Liao <liaoweixiong@allwinnertech.com>
Link: https://lore.kernel.org/lkml/20200511233229.27745-5-keescook@chromium.org/
Signed-off-by: Kees Cook <keescook@chromium.org>
pstore/blk is similar to pstore/ram, but uses a block device as the
storage rather than persistent ram.
The pstore/blk backend solves two common use-cases that used to preclude
using pstore/ram:
- not all devices have a battery that could be used to persist
regular RAM across power failures.
- most embedded intelligent equipment have no persistent ram, which
increases costs, instead preferring cheaper solutions, like block
devices.
pstore/blk provides separate configurations for the end user and for the
block drivers. User configuration determines how pstore/blk operates, such
as record sizes, max kmsg dump reasons, etc. These can be set by Kconfig
and/or module parameters, but module parameter have priority over Kconfig.
Driver configuration covers all the details about the target block device,
such as total size of the device and how to perform read/write operations.
These are provided by block drivers, calling pstore_register_blkdev(),
including an optional panic_write callback used to bypass regular IO
APIs in an effort to avoid potentially destabilized kernel code during
a panic.
Signed-off-by: WeiXiong Liao <liaoweixiong@allwinnertech.com>
Link: https://lore.kernel.org/lkml/20200511233229.27745-3-keescook@chromium.org/
Co-developed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Implement a common set of APIs needed to support pstore storage zones,
based on how ramoops is designed. This will be used by pstore/blk with
the intention of migrating pstore/ram in the future.
Signed-off-by: WeiXiong Liao <liaoweixiong@allwinnertech.com>
Link: https://lore.kernel.org/lkml/20200511233229.27745-2-keescook@chromium.org/
Co-developed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Now that pstore_register() can correctly pass max_reason to the kmesg
dump facility, introduce a new "max_reason" module parameter and
"max-reason" Device Tree field.
The "dump_oops" module parameter and "dump-oops" Device
Tree field are now considered deprecated, but are now automatically
converted to their corresponding max_reason values when present, though
the new max_reason setting has precedence.
For struct ramoops_platform_data, the "dump_oops" member is entirely
replaced by a new "max_reason" member, with the only existing user
updated in place.
Additionally remove the "reason" filter logic from ramoops_pstore_write(),
as that is not specifically needed anymore, though technically
this is a change in behavior for any ramoops users also setting the
printk.always_kmsg_dump boot param, which will cause ramoops to behave as
if max_reason was set to KMSG_DUMP_MAX.
Co-developed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Link: https://lore.kernel.org/lkml/20200515184434.8470-6-keescook@chromium.org/
Signed-off-by: Kees Cook <keescook@chromium.org>
Add a new member to struct pstore_info for passing information about
kmesg dump maximum reason. This allows a finer control of what kmesg
dumps are sent to pstore storage backends.
Those backends that do not explicitly set this field (keeping it equal to
0), get the default behavior: store only Oopses and Panics, or everything
if the printk.always_kmsg_dump boot param is set.
Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Link: https://lore.kernel.org/lkml/20200515184434.8470-5-keescook@chromium.org/
Co-developed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
The pstore subsystem already had a private version of this function.
With the coming addition of the pstore/zone driver, this needs to be
shared. As it really should live with printk, move it there instead.
Link: https://lore.kernel.org/lkml/20200515184434.8470-4-keescook@chromium.org/
Acked-by: Petr Mladek <pmladek@suse.com>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
This changes the ftrace record merging code to be agnostic of
pstore/ram, as the first step to making it available as a generic
routine for other backends to use, such as pstore/zone.
Link: https://lore.kernel.org/lkml/20200510202436.63222-6-keescook@chromium.org/
Signed-off-by: Kees Cook <keescook@chromium.org>
In order to more cleanly pass around backend names, make the "name" member
const. This means the module param needs to be dynamic (technically, it
was before, so this actually cleans up a minor memory leak if a backend
was specified and then gets unloaded.)
Link: https://lore.kernel.org/lkml/20200510202436.63222-3-keescook@chromium.org/
Signed-off-by: Kees Cook <keescook@chromium.org>
The CON_ENABLED flag gets cleared during unregister_console(), so make
sure we already reset the console flags before calling register_console(),
otherwise unloading and reloading a pstore backend will not restart
console logging.
Signed-off-by: Kees Cook <keescook@chromium.org>
If a backend was unloaded without having first removed all its
associated records in pstorefs, subsequent removals would crash while
attempting to call into the now missing backend. Add automatic removal
from the tree in pstore_unregister(), so that no references to the
backend remain.
Reported-by: Luis Henriques <lhenriques@suse.com>
Link: https://lore.kernel.org/lkml/87o8yrmv69.fsf@suse.com
Link: https://lore.kernel.org/lkml/20200506152114.50375-11-keescook@chromium.org/
Signed-off-by: Kees Cook <keescook@chromium.org>
The pstore.update_ms value was being disabled during pstore_unregister(),
which would cause any prior value to go unnoticed on the next
pstore_register(). Instead, just let del_timer() stop the timer, which
was always sufficient. This additionally refactors the timer reset code
and allows the timer to be enabled if the module parameter is changed
away from the default.
Link: https://lore.kernel.org/lkml/20200506152114.50375-10-keescook@chromium.org/
Signed-off-by: Kees Cook <keescook@chromium.org>
Nothing was protecting changes to the pstorefs superblock. Add locking
and refactor away is_pstore_mounted(), instead using a helper to add a
way to safely lock the pstorefs root inode during filesystem changes.
Link: https://lore.kernel.org/lkml/20200506152114.50375-9-keescook@chromium.org/
Signed-off-by: Kees Cook <keescook@chromium.org>
The "unlink" handling should perform list removal (which can also make
sure records don't get double-erased), and the "evict" handling should
be responsible only for memory freeing.
Link: https://lore.kernel.org/lkml/20200506152114.50375-8-keescook@chromium.org/
Signed-off-by: Kees Cook <keescook@chromium.org>
The pstorefs internal list lock doesn't need to be a spinlock and will
create problems when trying to access the list in the subsequent patch
that will walk the pstorefs records during pstore_unregister(). Change
this to a mutex to avoid may_sleep() warnings when unregistering devices.
Link: https://lore.kernel.org/lkml/20200506152114.50375-6-keescook@chromium.org/
Signed-off-by: Kees Cook <keescook@chromium.org>
The name "allpstore" doesn't carry much meaning, so rename it to what it
actually is: the list of all records present in the filesystem. The lock
is also renamed accordingly.
Link: https://lore.kernel.org/lkml/20200506152114.50375-5-keescook@chromium.org/
Signed-off-by: Kees Cook <keescook@chromium.org>
Currently pstore can only have a single backend attached at a time, and it
tracks the active backend via "psinfo", under a lock. The locking for this
does not need to be a spinlock, and in order to avoid may_sleep() issues
during future changes to pstore_unregister(), switch to a mutex instead.
Link: https://lore.kernel.org/lkml/20200506152114.50375-4-keescook@chromium.org/
Signed-off-by: Kees Cook <keescook@chromium.org>
There is no reason to be doing a module get/put in pstore_register(),
since the module calling pstore_register() cannot be unloaded since it
hasn't finished its initialization. Remove it so there is no confusion
about how registration ordering works.
Link: https://lore.kernel.org/lkml/20200506152114.50375-2-keescook@chromium.org/
Signed-off-by: Kees Cook <keescook@chromium.org>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Link: https://lore.kernel.org/r/20200309202327.GA8813@embeddedor
Signed-off-by: Kees Cook <keescook@chromium.org>
In Aug 2018 NeilBrown noticed
commit 1f4aace60b ("fs/seq_file.c: simplify seq_file iteration code and interface")
"Some ->next functions do not increment *pos when they return NULL...
Note that such ->next functions are buggy and should be fixed.
A simple demonstration is
dd if=/proc/swaps bs=1000 skip=1
Choose any block size larger than the size of /proc/swaps. This will
always show the whole last line of /proc/swaps"
/proc/swaps output was fixed recently, however there are lot of other
affected files, and one of them is related to pstore subsystem.
If .next function does not change position index, following .show function
will repeat output related to current position index.
There are at least 2 related problems:
- read after lseek beyond end of file, described above by NeilBrown
"dd if=<AFFECTED_FILE> bs=1000 skip=1" will generate whole last list
- read after lseek on in middle of last line will output expected rest of
last line but then repeat whole last line once again.
If .show() function generates multy-line output (like
pstore_ftrace_seq_show() does ?) following bash script cycles endlessly
$ q=;while read -r r;do echo "$((++q)) $r";done < AFFECTED_FILE
Unfortunately I'm not familiar enough to pstore subsystem and was unable
to find affected pstore-related file on my test node.
If .next function does not change position index, following .show function
will repeat output related to current position index.
Cc: stable@vger.kernel.org
Fixes: 1f4aace60b ("fs/seq_file.c: simplify seq_file iteration code ...")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206283
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Link: https://lore.kernel.org/r/4e49830d-4c88-0171-ee24-1ee540028dad@virtuozzo.com
[kees: with robustness tweak from Joel Fernandes <joelaf@google.com>]
Signed-off-by: Kees Cook <keescook@chromium.org>
There is a potential mem leak when pstore_init_fs failed,
since the pstore compression maybe unlikey to initialized
successfully. We must clean up the allocation once this
unlikey issue happens.
Signed-off-by: chenqiwu <chenqiwu@xiaomi.com>
Link: https://lore.kernel.org/r/1581068800-13817-1-git-send-email-qiwuchen55@gmail.com
Signed-off-by: Kees Cook <keescook@chromium.org>
In my attempt to fix a memory leak, I introduced a double-free in the
pstore error path. Instead of trying to manage the allocation lifetime
between persistent_ram_new() and its callers, adjust the logic so
persistent_ram_new() always takes a kstrdup() copy, and leaves the
caller's allocation lifetime up to the caller. Therefore callers are
_always_ responsible for freeing their label. Before, it only needed
freeing when the prz itself failed to allocate, and not in any of the
other prz failure cases, which callers would have no visibility into,
which is the root design problem that lead to both the leak and now
double-free bugs.
Reported-by: Cengiz Can <cengiz@kernel.wtf>
Link: https://lore.kernel.org/lkml/d4ec59002ede4aaf9928c7f7526da87c@kernel.wtf
Fixes: 8df955a32a ("pstore/ram: Fix error-path memory leak in persistent_ram_new() callers")
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
The ram_core.c routines treat przs as circular buffers. When writing a
new crash dump, the old buffer needs to be cleared so that the new dump
doesn't end up in the wrong place (i.e. at the end).
The solution to this problem is to reset the circular buffer state before
writing a new Oops dump.
Signed-off-by: Aleksandr Yashkin <a.yashkin@inango-systems.com>
Signed-off-by: Nikolay Merinov <n.merinov@inango-systems.com>
Signed-off-by: Ariel Gilman <a.gilman@inango-systems.com>
Link: https://lore.kernel.org/r/20191223133816.28155-1-n.merinov@inango-systems.com
Fixes: 896fc1f0c4 ("pstore/ram: Switch to persistent_ram routines")
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
The pstore_choose_compression() function is not exported so make it
static to avoid the following sparse warning:
fs/pstore/platform.c:796:13: warning: symbol 'pstore_choose_compression' was not declared. Should it be static?
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Link: https://lore.kernel.org/r/20191016123317.3154-1-ben.dooks@codethink.co.uk
Fixes: cb095afd44 ("pstore: Centralize init/exit routines")
Signed-off-by: Kees Cook <keescook@chromium.org>
Leaving granularity at 1ns because it is dependent on the specific
attached backing pstore module. ramoops has microsecond resolution.
Fix the readback of ramoops fractional timestamp microseconds,
which has incorrectly been reporting the value as nanoseconds.
Fixes: 3f8f80f0cf ("pstore/ram: Read and write to the 'compressed' flag of pstore").
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Jeff Layton <jlayton@kernel.org>
Cc: anton@enomsg.org
Cc: ccross@android.com
Cc: keescook@chromium.org
Cc: tony.luck@intel.com
The pstore_mkfile() function is passed a pointer to a struct
pstore_record. On success it consumes this 'record' pointer and
references it from the created inode.
On failure, however, it may or may not free the record. There are even
two different code paths which return -ENOMEM -- one of which does and
the other doesn't free the record.
Make the behaviour deterministic by never consuming and freeing the
record when returning failure, allowing the caller to do the cleanup
consistently.
Signed-off-by: Norbert Manthey <nmanthey@amazon.de>
Link: https://lore.kernel.org/r/1562331960-26198-1-git-send-email-nmanthey@amazon.de
Fixes: 83f70f0769 ("pstore: Do not duplicate record metadata")
Fixes: 1dfff7dd67 ("pstore: Pass record contents instead of copying")
Cc: stable@vger.kernel.org
[kees: also move "private" allocation location, rename inode cleanup label]
Signed-off-by: Kees Cook <keescook@chromium.org>
When calling debugfs functions, there is no need to ever check the
return value. The function can work or not, but the code logic should
never do something different based on this.
Cc: Kees Cook <keescook@chromium.org>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
When you try to run an upstream kernel on an old ARM-based Chromebook
you'll find that console-ramoops doesn't work.
Old ARM-based Chromebooks, before <https://crrev.com/c/439792>
("ramoops: support upstream {console,pmsg,ftrace}-size properties")
used to create a "ramoops" node at the top level that looked like:
/ {
ramoops {
compatible = "ramoops";
reg = <...>;
record-size = <...>;
dump-oops;
};
};
...and these Chromebooks assumed that the downstream kernel would make
console_size / pmsg_size match the record size. The above ramoops
node was added by the firmware so it's not easy to make any changes.
Let's match the expected behavior, but only for those using the old
backward-compatible way of working where ramoops is right under the
root node.
NOTE: if there are some out-of-tree devices that had ramoops at the
top level, left everything but the record size as 0, and somehow
doesn't want this behavior, we can try to add more conditions here.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Another round of SPDX header file fixes for 5.2-rc4
These are all more "GPL-2.0-or-later" or "GPL-2.0-only" tags being
added, based on the text in the files. We are slowly chipping away at
the 700+ different ways people tried to write the license text. All of
these were reviewed on the spdx mailing list by a number of different
people.
We now have over 60% of the kernel files covered with SPDX tags:
$ ./scripts/spdxcheck.py -v 2>&1 | grep Files
Files checked: 64533
Files with SPDX: 40392
Files with errors: 0
I think the majority of the "easy" fixups are now done, it's now the
start of the longer-tail of crazy variants to wade through.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'spdx-5.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull yet more SPDX updates from Greg KH:
"Another round of SPDX header file fixes for 5.2-rc4
These are all more "GPL-2.0-or-later" or "GPL-2.0-only" tags being
added, based on the text in the files. We are slowly chipping away at
the 700+ different ways people tried to write the license text. All of
these were reviewed on the spdx mailing list by a number of different
people.
We now have over 60% of the kernel files covered with SPDX tags:
$ ./scripts/spdxcheck.py -v 2>&1 | grep Files
Files checked: 64533
Files with SPDX: 40392
Files with errors: 0
I think the majority of the "easy" fixups are now done, it's now the
start of the longer-tail of crazy variants to wade through"
* tag 'spdx-5.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (159 commits)
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 450
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 449
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 448
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 446
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 445
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 444
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 443
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 442
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 440
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 438
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 437
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 436
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 435
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 434
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 433
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 432
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 431
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 430
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 429
...
- Avoid NULL deref when unloading/reloading ramoops module (Pi-Hsun Shih)
- Run ramoops without crash dump region
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Comment: Kees Cook <kees@outflux.net>
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Merge tag 'pstore-v5.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull pstore fixes from Kees Cook:
- Avoid NULL deref when unloading/reloading ramoops module (Pi-Hsun
Shih)
- Run ramoops without crash dump region
* tag 'pstore-v5.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
pstore/ram: Run without kernel crash dump region
pstore: Set tfm to NULL on free_buf_for_compression
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation this program is
distributed in the hope that it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details you should have received a copy of the gnu general
public license along with this program if not write to the free
software foundation inc 51 franklin st fifth floor boston ma 02110
1301 usa
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 246 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190530000436.674189849@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation this program is
distributed in the hope that it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details you should have received a copy of the gnu general
public license along with this program if not write to the free
software foundation inc 59 temple place suite 330 boston ma 02111
1307 usa
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 136 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190530000436.384967451@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Based on 1 normalized pattern(s):
this software is licensed under the terms of the gnu general public
license version 2 as published by the free software foundation and
may be copied distributed and modified under those terms this
program is distributed in the hope that it will be useful but
without any warranty without even the implied warranty of
merchantability or fitness for a particular purpose see the gnu
general public license for more details
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 285 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141900.642774971@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The ram pstore backend has always had the crash dumper frontend enabled
unconditionally. However, it was possible to effectively disable it
by setting a record_size=0. All the machinery would run (storing dumps
to the temporary crash buffer), but 0 bytes would ultimately get stored
due to there being no przs allocated for dumps. Commit 89d328f637
("pstore/ram: Correctly calculate usable PRZ bytes"), however, assumed
that there would always be at least one allocated dprz for calculating
the size of the temporary crash buffer. This was, of course, not the
case when record_size=0, and would lead to a NULL deref trying to find
the dprz buffer size:
BUG: unable to handle kernel NULL pointer dereference at (null)
...
IP: ramoops_probe+0x285/0x37e (fs/pstore/ram.c:808)
cxt->pstore.bufsize = cxt->dprzs[0]->buffer_size;
Instead, we need to only enable the frontends based on the success of the
prz initialization and only take the needed actions when those zones are
available. (This also fixes a possible error in detecting if the ftrace
frontend should be enabled.)
Reported-and-tested-by: Yaro Slav <yaro330@gmail.com>
Fixes: 89d328f637 ("pstore/ram: Correctly calculate usable PRZ bytes")
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Set tfm to NULL on free_buf_for_compression() after crypto_free_comp().
This avoid a use-after-free when allocate_buf_for_compression()
and free_buf_for_compression() are called twice. Although
free_buf_for_compression() freed the tfm, allocate_buf_for_compression()
won't reinitialize the tfm since the tfm pointer is not NULL.
Fixes: 95047b0519 ("pstore: Refactor compression initialization")
Signed-off-by: Pi-Hsun Shih <pihsun@chromium.org>
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Add SPDX license identifiers to all Make/Kconfig files which:
- Have no license information of any form
These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:
GPL-2.0-only
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since the header is a fixed small maximum size, just use a stack variable
to avoid memory allocation in the write path.
Signed-off-by: Kees Cook <keescook@chromium.org>
If zero-length header happened in ramoops_write_kmsg_hdr(), that means
we will not be able to read back dmesg record later, since it will be
treated as invalid header in ramoops_pstore_read(). So we should not
execute the following code but return the error.
Signed-off-by: Yue Hu <huyue2@yulong.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Since only one single ramoops area allowed at a time, other probes
(like device tree) are meaningless, as it will waste CPU resources.
So let's check for being already initialized first.
Signed-off-by: Yue Hu <huyue2@yulong.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Sometimes pstore_console_write() will write records with zero size
to persistent ram zone, which is unnecessary. It will only increase
resource consumption. Also adjust ramoops_write_kmsg_hdr() to have
same logic if memory allocation fails.
Signed-off-by: Yue Hu <huyue2@yulong.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
In ramoops_register_dummy() dummy_data is allocated via kzalloc()
then it will always occupy the heap space after register platform
device via platform_device_register_data(), but it will not be
used any more. So let's free it for system usage, replace it with
stack memory is better due to small size.
Signed-off-by: Yue Hu <huyue2@yulong.com>
[kees: add required memset and adjust sizeof() argument]
Signed-off-by: Kees Cook <keescook@chromium.org>
Yue Hu noticed that when parsing device tree the allocated platform data
was never freed. Since it's not used beyond the function scope, this
switches to using a stack variable instead.
Reported-by: Yue Hu <huyue2@yulong.com>
Fixes: 35da60941e ("pstore/ram: add Device Tree bindings")
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
commit b05c950698 ("pstore/ram: Simplify ramoops_get_next_prz()
arguments") changed update assignment in getting next persistent ram zone
by adding a check for record type. But the check always returns true since
the record type is assigned 0. And this breaks console ramoops by showing
current console log instead of previous log on warm reset and hard reset
(actually hard reset should not be showing any logs).
Fix this by having persistent ram zone type check instead of record type
check. Tested this on SDM845 MTP and dragonboard 410c.
Reproducing this issue is simple as below:
1. Trigger hard reset and mount pstore. Will see console-ramoops
record in the mounted location which is the current log.
2. Trigger warm reset and mount pstore. Will see the current
console-ramoops record instead of previous record.
Fixes: b05c950698 ("pstore/ram: Simplify ramoops_get_next_prz() arguments")
Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Acked-by: Joel Fernandes (Google) <joel@joelfernandes.org>
[kees: dropped local variable usage]
Signed-off-by: Kees Cook <keescook@chromium.org>
Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.
It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access. But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.
A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model. And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.
This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.
There were a couple of notable cases:
- csky still had the old "verify_area()" name as an alias.
- the iter_iov code had magical hardcoded knowledge of the actual
values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
really used it)
- microblaze used the type argument for a debug printout
but other than those oddities this should be a total no-op patch.
I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something. Any missed conversion should be trivially fixable, though.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Given corruption in the ftrace records, it might be possible to allocate
tmp_prz without assigning prz to it, but still marking it as needing to
be freed, which would cause at least a NULL dereference.
smatch warnings:
fs/pstore/ram.c:340 ramoops_pstore_read() error: we previously assumed 'prz' could be null (see line 255)
https://lists.01.org/pipermail/kbuild-all/2018-December/055528.html
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: 2fbea82bbb ("pstore: Merge per-CPU ftrace records into one")
Cc: "Joel Fernandes (Google)" <joel@joelfernandes.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Instead of running with interrupts disabled, use a semaphore. This should
make it easier for backends that may need to sleep (e.g. EFI) when
performing a write:
|BUG: sleeping function called from invalid context at kernel/sched/completion.c:99
|in_atomic(): 1, irqs_disabled(): 1, pid: 2236, name: sig-xstate-bum
|Preemption disabled at:
|[<ffffffff99d60512>] pstore_dump+0x72/0x330
|CPU: 26 PID: 2236 Comm: sig-xstate-bum Tainted: G D 4.20.0-rc3 #45
|Call Trace:
| dump_stack+0x4f/0x6a
| ___might_sleep.cold.91+0xd3/0xe4
| __might_sleep+0x50/0x90
| wait_for_completion+0x32/0x130
| virt_efi_query_variable_info+0x14e/0x160
| efi_query_variable_store+0x51/0x1a0
| efivar_entry_set_safe+0xa3/0x1b0
| efi_pstore_write+0x109/0x140
| pstore_dump+0x11c/0x330
| kmsg_dump+0xa4/0xd0
| oops_exit+0x22/0x30
...
Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Fixes: 21b3ddd39f ("efi: Don't use spinlocks for efi vars")
Signed-off-by: Kees Cook <keescook@chromium.org>
Bool initializations should use true and false. Bool tests don't need
comparisons.
Signed-off-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Kees Cook <keescook@chromium.org>
The ramoops backend currently calls persistent_ram_save_old() even
if a buffer is empty. While this appears to work, it is does not seem
like the right thing to do and could lead to future bugs so lets avoid
that. It also prevents misleading prints in the logs which claim the
buffer is valid.
I got something like:
found existing buffer, size 0, start 0
When I was expecting:
no valid data in buffer (sig = ...)
This bails out early (and reports with pr_debug()), since it's an
acceptable state.
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Co-developed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
(1) remove type argument from ramoops_get_next_prz()
Since we store the type of the prz when we initialize it, we no longer
need to pass it again in ramoops_get_next_prz() since we can just use
that to setup the pstore record. So lets remove it from the argument list.
(2) remove max argument from ramoops_get_next_prz()
Looking at the code flow, the 'max' checks are already being done on
the prz passed to ramoops_get_next_prz(). Lets remove it to simplify
this function and reduce its arguments.
(3) further reduce ramoops_get_next_prz() arguments by passing record
Both the id and type fields of a pstore_record are set by
ramoops_get_next_prz(). So we can just pass a pointer to the pstore_record
instead of passing individual elements. This results in cleaner more
readable code and fewer lines.
In addition lets also remove the 'update' argument since we can detect
that. Changes are squashed into a single patch to reduce fixup conflicts.
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
In later patches we will need to map types to names, so create a
constant table for that which can also be used in different parts of
old and new code. This saves the type in the PRZ which will be useful
in later patches.
Instead of having an explicit PSTORE_TYPE_UNKNOWN, just use ..._MAX.
This includes removing the now redundant filename templates which can use
a single format string. Also, there's no reason to limit the "is it still
compressed?" test to only PSTORE_TYPE_DMESG when building the pstorefs
filename. Records are zero-initialized, so a backend would need to have
explicitly set compressed=1.
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Co-developed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
This improves and updates some comments:
- dump handler comment out of sync from calling convention
- fix kern-doc typo
and improves status output:
- reminder that only kernel crash dumps are compressed
- do not be silent about ECC infrastructure failures
Signed-off-by: Kees Cook <keescook@chromium.org>
In order to more easily perform automated regression testing, this
adds pr_debug() calls to report each prz allocation which can then be
verified against persistent storage. Specifically, seeing the dividing
line between header, data, any ECC bytes. (And the general assignment
output is updated to remove the bogus ECC blocksize which isn't actually
recorded outside the prz instance.)
Signed-off-by: Kees Cook <keescook@chromium.org>
With both ram.c and ram_core.c built into ramoops.ko, it doesn't make
sense to have differing pr_fmt prefixes. This fixes ram_core.c to use
the module name (as ram.c already does). Additionally improves region
reservation error to include the region name.
Signed-off-by: Kees Cook <keescook@chromium.org>
When initialing a prz, if invalid data is found (no PERSISTENT_RAM_SIG),
the function call path looks like this:
ramoops_init_prz ->
persistent_ram_new -> persistent_ram_post_init -> persistent_ram_zap
persistent_ram_zap
As we can see, persistent_ram_zap() is called twice.
We can avoid this by adding an option to persistent_ram_new(), and
only call persistent_ram_zap() when it is needed.
Signed-off-by: Peng Wang <wangpeng15@xiaomi.com>
[kees: minor tweak to exit path and commit log]
Signed-off-by: Kees Cook <keescook@chromium.org>
Since the console writer does not use the preallocated crash dump buffer
any more, there is no reason to perform locking around it.
Fixes: 70ad35db33 ("pstore: Convert console write to use ->write_buf")
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
The pre-allocated compression buffer used for crash dumping was also
being used for decompression. This isn't technically safe, since it's
possible the kernel may attempt a crashdump while pstore is populating the
pstore filesystem (and performing decompression). Instead, just allocate
a separate buffer for decompression. Correctness is preferred over
performance here.
Signed-off-by: Kees Cook <keescook@chromium.org>
The actual number of bytes stored in a PRZ is smaller than the
bytes requested by platform data, since there is a header on each
PRZ. Additionally, if ECC is enabled, there are trailing bytes used
as well. Normally this mismatch doesn't matter since PRZs are circular
buffers and the leading "overflow" bytes are just thrown away. However, in
the case of a compressed record, this rather badly corrupts the results.
This corruption was visible with "ramoops.mem_size=204800 ramoops.ecc=1".
Any stored crashes would not be uncompressable (producing a pstorefs
"dmesg-*.enc.z" file), and triggering errors at boot:
[ 2.790759] pstore: crypto_comp_decompress failed, ret = -22!
Backporting this depends on commit 70ad35db33 ("pstore: Convert console
write to use ->write_buf")
Reported-by: Joel Fernandes <joel@joelfernandes.org>
Fixes: b0aad7a99c ("pstore: Add compression support to pstore")
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
All architecures use memblock for early memory management. There is no need
for the CONFIG_HAVE_MEMBLOCK configuration option.
[rppt@linux.vnet.ibm.com: of/fdt: fixup #ifdefs]
Link: http://lkml.kernel.org/r/20180919103457.GA20545@rapoport-lnx
[rppt@linux.vnet.ibm.com: csky: fixups after bootmem removal]
Link: http://lkml.kernel.org/r/20180926112744.GC4628@rapoport-lnx
[rppt@linux.vnet.ibm.com: remove stale #else and the code it protects]
Link: http://lkml.kernel.org/r/1538067825-24835-1-git-send-email-rppt@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1536927045-23536-4-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Tested-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Serge Semin <fancer.lancer@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When ramoops reserved a memory region in the kernel, it had an unhelpful
label of "persistent_memory". When reading /proc/iomem, it would be
repeated many times, did not hint that it was ramoops in particular,
and didn't clarify very much about what each was used for:
400000000-407ffffff : Persistent Memory (legacy)
400000000-400000fff : persistent_memory
400001000-400001fff : persistent_memory
...
4000ff000-4000fffff : persistent_memory
Instead, this adds meaningful labels for how the various regions are
being used:
400000000-407ffffff : Persistent Memory (legacy)
400000000-400000fff : ramoops:dump(0/252)
400001000-400001fff : ramoops:dump(1/252)
...
4000fc000-4000fcfff : ramoops:dump(252/252)
4000fd000-4000fdfff : ramoops:console
4000fe000-4000fe3ff : ramoops:ftrace(0/3)
4000fe400-4000fe7ff : ramoops:ftrace(1/3)
4000fe800-4000febff : ramoops:ftrace(2/3)
4000fec00-4000fefff : ramoops:ftrace(3/3)
4000ff000-4000fffff : ramoops:pmsg
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Tested-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Tested-by: Guenter Roeck <groeck@chromium.org>
This refactors compression initialization slightly to better handle
getting potentially called twice (via early pstore_register() calls
and later pstore_init()) and improves the comments and reporting to be
more verbose.
Signed-off-by: Kees Cook <keescook@chromium.org>
Tested-by: Guenter Roeck <groeck@chromium.org>
ramoops's call of pstore_register() was recently moved to run during
late_initcall() because the crypto backend may not have been ready during
postcore_initcall(). This meant early-boot crash dumps were not getting
caught by pstore any more.
Instead, lets allow calls to pstore_register() earlier, and once crypto
is ready we can initialize the compression.
Reported-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Tested-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Fixes: cb3bee0369 ("pstore: Use crypto compress API")
[kees: trivial rebase]
Signed-off-by: Kees Cook <keescook@chromium.org>
Tested-by: Guenter Roeck <groeck@chromium.org>
In preparation for having additional actions during init/exit, this moves
the init/exit into platform.c, centralizing the logic to make call outs
to the fs init/exit.
Signed-off-by: Kees Cook <keescook@chromium.org>
Tested-by: Guenter Roeck <groeck@chromium.org>
As reported by nixiaoming, with some minor clarifications:
1) memory leak in ramoops_register_dummy():
dummy_data = kzalloc(sizeof(*dummy_data), GFP_KERNEL);
but no kfree() if platform_device_register_data() fails.
2) memory leak in ramoops_init():
Missing platform_device_unregister(dummy) and kfree(dummy_data)
if platform_driver_register(&ramoops_driver) fails.
I've clarified the purpose of ramoops_register_dummy(), and added a
common cleanup routine for all three failure paths to call.
Reported-by: nixiaoming <nixiaoming@huawei.com>
Cc: stable@vger.kernel.org
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
persistent_ram_vmap() returns the page start vaddr.
persistent_ram_iomap() supports non-page-aligned mapping.
persistent_ram_buffer_map() always adds offset-in-page to the vaddr
returned from these two functions, which causes incorrect mapping of
non-page-aligned persistent ram buffer.
By default ftrace_size is 4096 and max_ftrace_cnt is nr_cpu_ids. Without
this patch, the zone_sz in ramoops_init_przs() is 4096/nr_cpu_ids which
might not be page aligned. If the offset-in-page > 2048, the vaddr will be
in next page. If the next page is not mapped, it will cause kernel panic:
[ 0.074231] BUG: unable to handle kernel paging request at ffffa19e0081b000
...
[ 0.075000] RIP: 0010:persistent_ram_new+0x1f8/0x39f
...
[ 0.075000] Call Trace:
[ 0.075000] ramoops_init_przs.part.10.constprop.15+0x105/0x260
[ 0.075000] ramoops_probe+0x232/0x3a0
[ 0.075000] platform_drv_probe+0x3e/0xa0
[ 0.075000] driver_probe_device+0x2cd/0x400
[ 0.075000] __driver_attach+0xe4/0x110
[ 0.075000] ? driver_probe_device+0x400/0x400
[ 0.075000] bus_for_each_dev+0x70/0xa0
[ 0.075000] driver_attach+0x1e/0x20
[ 0.075000] bus_add_driver+0x159/0x230
[ 0.075000] ? do_early_param+0x95/0x95
[ 0.075000] driver_register+0x70/0xc0
[ 0.075000] ? init_pstore_fs+0x4d/0x4d
[ 0.075000] __platform_driver_register+0x36/0x40
[ 0.075000] ramoops_init+0x12f/0x131
[ 0.075000] do_one_initcall+0x4d/0x12c
[ 0.075000] ? do_early_param+0x95/0x95
[ 0.075000] kernel_init_freeable+0x19b/0x222
[ 0.075000] ? rest_init+0xbb/0xbb
[ 0.075000] kernel_init+0xe/0xfc
[ 0.075000] ret_from_fork+0x3a/0x50
Signed-off-by: Bin Yang <bin.yang@intel.com>
[kees: add comments describing the mapping differences, updated commit log]
Fixes: 24c3d2f342 ("staging: android: persistent_ram: Make it possible to use memory outside of bootmem")
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
This patch added the 6th compression algorithm support for pstore: zstd.
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
The pstore conversion to timespec64 introduces its own method of passing
seconds into sscanf() and sprintf() type functions to work around the
timespec64 definition on 64-bit systems that redefine it to 'timespec'.
That hack is now finally getting removed, but that means we get a (harmless)
warning once both patches are merged:
fs/pstore/ram.c: In function 'ramoops_read_kmsg_hdr':
fs/pstore/ram.c:39:29: error: format '%ld' expects argument of type 'long int *', but argument 3 has type 'time64_t *' {aka 'long long int *'} [-Werror=format=]
#define RAMOOPS_KERNMSG_HDR "===="
^~~~~~
fs/pstore/ram.c:167:21: note: in expansion of macro 'RAMOOPS_KERNMSG_HDR'
This removes the pstore specific workaround and uses the same method that
we have in place for all other functions that print a timespec64.
Related to this, I found that the kasprintf() output contains an incorrect
nanosecond values for any number starting with zeroes, and I adapt the
format string accordingly.
Link: https://lkml.org/lkml/2018/5/19/115
Link: https://lkml.org/lkml/2018/5/16/1080
Fixes: 0f0d83b99ef7 ("pstore: Convert internal records to timespec64")
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
This prepares pstore for converting the VFS layer to timespec64.
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Commit 58eb5b6707 ("pstore: fix crypto dependencies") fixed up the crypto
dependencies but missed the case when no compression is selected.
With CONFIG_PSTORE=y, CONFIG_PSTORE_COMPRESS=n and CONFIG_CRYPTO=m we see
the following link error:
fs/pstore/platform.o: In function `pstore_register':
(.text+0x1b1): undefined reference to `crypto_has_alg'
(.text+0x205): undefined reference to `crypto_alloc_base'
fs/pstore/platform.o: In function `pstore_unregister':
(.text+0x3b0): undefined reference to `crypto_destroy_tfm'
Fix this by checking at compile-time if CONFIG_PSTORE_COMPRESS is enabled.
Fixes: 58eb5b6707 ("pstore: fix crypto dependencies")
Signed-off-by: Tobias Regnery <tobias.regnery@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Kees Cook <keescook@chromium.org>
The new crypto API use causes some problems with Kconfig dependencies,
including this link error:
fs/pstore/platform.o: In function `pstore_register':
platform.c:(.text+0x248): undefined reference to `crypto_has_alg'
platform.c:(.text+0x2a0): undefined reference to `crypto_alloc_base'
fs/pstore/platform.o: In function `pstore_unregister':
platform.c:(.text+0x498): undefined reference to `crypto_destroy_tfm'
crypto/lz4hc.o: In function `lz4hc_sdecompress':
lz4hc.c:(.text+0x1a): undefined reference to `LZ4_decompress_safe'
crypto/lz4hc.o: In function `lz4hc_decompress_crypto':
lz4hc.c:(.text+0x5a): undefined reference to `LZ4_decompress_safe'
crypto/lz4hc.o: In function `lz4hc_scompress':
lz4hc.c:(.text+0xaa): undefined reference to `LZ4_compress_HC'
crypto/lz4hc.o: In function `lz4hc_mod_init':
lz4hc.c:(.init.text+0xf): undefined reference to `crypto_register_alg'
lz4hc.c:(.init.text+0x1f): undefined reference to `crypto_register_scomp'
lz4hc.c:(.init.text+0x2f): undefined reference to `crypto_unregister_alg'
The problem is that with CONFIG_CRYPTO=m, we must not 'select CRYPTO_LZ4'
from a bool symbol, or call crypto API functions from a built-in
module.
This turns the sub-options into 'tristate' ones so the dependencies
are honored, and makes the pstore itself select the crypto core
if necessary.
Fixes: cb3bee0369 ("pstore: Use crypto compress API")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Kees Cook <keescook@chromium.org>
In the pstore compression part, we use zlib/lzo/lz4/lz4hc/842
compression algorithm API to implement pstore compression backends. But
there are many repeat codes in these implementations. This patch uses
crypto compress API to simplify these codes.
1) rewrite allocate_buf_for_compression, free_buf_for_compression,
pstore_compress, pstore_decompress functions using crypto compress API.
2) drop compress, decompress, allocate, free functions in pstore_zbackend,
and add zbufsize function to get each different compress buffer size.
3) use late_initcall to call ramoops_init later, to make sure the crypto
subsystem has already initialized.
4) use 'unsigned int' type instead of 'size_t' in pstore_compress,
pstore_decompress functions' length arguments.
5) rename 'zlib' to 'deflate' to follow the crypto API's name convention.
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
[kees: tweaked error messages on allocation failures and Kconfig help]
Signed-off-by: Kees Cook <keescook@chromium.org>
Instead of using a stack VLA for the parity workspace, preallocate a
memory region. The preallocation is done to keep from needing to perform
allocations during crash dump writing, etc. This also fixes a missed
release of librs on free.
Signed-off-by: Kees Cook <keescook@chromium.org>
To allow for easier build test coverage and run-time testing, this allows
multiple compression algorithms to be built into pstore. Still only one
is supported to operate at a time (which can be selected at build time
or at boot time, similar to how LSMs are selected).
Signed-off-by: Kees Cook <keescook@chromium.org>
Instead of casting, make sure we don't end up with giant values and just
perform regular assignments with unsigned int instead of re-cast size_t.
Signed-off-by: Kees Cook <keescook@chromium.org>
Currently, pstore has supported three compression algorithms: zlib,
lzo and lz4. This patch added two more compression algorithms: lz4hc
and 842.
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
[kees: tweaked Kconfig help text slightly]
Signed-off-by: Kees Cook <keescook@chromium.org>
Preempt counter APIs have been split out, currently, hardirq.h just
includes irq_enter/exit APIs which are not used by pstore at all.
So, remove the unused hardirq.h.
Signed-off-by: Yang Shi <yang.s@alibaba-inc.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
This changes all DEFINE_TIMER() callbacks to use a struct timer_list
pointer instead of unsigned long. Since the data argument has already been
removed, none of these callbacks are using their argument currently, so
this renames the argument to "unused".
Done using the following semantic patch:
@match_define_timer@
declarer name DEFINE_TIMER;
identifier _timer, _callback;
@@
DEFINE_TIMER(_timer, _callback);
@change_callback depends on match_define_timer@
identifier match_define_timer._callback;
type _origtype;
identifier _origarg;
@@
void
-_callback(_origtype _origarg)
+_callback(struct timer_list *unused)
{ ... }
Signed-off-by: Kees Cook <keescook@chromium.org>
Pull misc vfs updates from Al Viro:
"Assorted stuff, really no common topic here"
* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
vfs: grab the lock instead of blocking in __fd_install during resizing
vfs: stop clearing close on exec when closing a fd
include/linux/fs.h: fix comment about struct address_space
fs: make fiemap work from compat_ioctl
coda: fix 'kernel memory exposure attempt' in fsync
pstore: remove unneeded unlikely()
vfs: remove unneeded unlikely()
stubs for mount_bdev() and kill_block_super() in !CONFIG_BLOCK case
make vfs_ustat() static
do_handle_open() should be static
elf_fdpic: fix unused variable warning
fold destroy_super() into __put_super()
new helper: destroy_unused_super()
fix address space warnings in ipc/
acct.h: get rid of detritus
Pull timer updates from Thomas Gleixner:
"Yet another big pile of changes:
- More year 2038 work from Arnd slowly reaching the point where we
need to think about the syscalls themself.
- A new timer function which allows to conditionally (re)arm a timer
only when it's either not running or the new expiry time is sooner
than the armed expiry time. This allows to use a single timer for
multiple timeout requirements w/o caring about the first expiry
time at the call site.
- A new NMI safe accessor to clock real time for the printk timestamp
work. Can be used by tracing, perf as well if required.
- A large number of timer setup conversions from Kees which got
collected here because either maintainers requested so or they
simply got ignored. As Kees pointed out already there are a few
trivial merge conflicts and some redundant commits which was
unavoidable due to the size of this conversion effort.
- Avoid a redundant iteration in the timer wheel softirq processing.
- Provide a mechanism to treat RTC implementations depending on their
hardware properties, i.e. don't inflict the write at the 0.5
seconds boundary which originates from the PC CMOS RTC to all RTCs.
No functional change as drivers need to be updated separately.
- The usual small updates to core code clocksource drivers. Nothing
really exciting"
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (111 commits)
timers: Add a function to start/reduce a timer
pstore: Use ktime_get_real_fast_ns() instead of __getnstimeofday()
timer: Prepare to change all DEFINE_TIMER() callbacks
netfilter: ipvs: Convert timers to use timer_setup()
scsi: qla2xxx: Convert timers to use timer_setup()
block/aoe: discover_timer: Convert timers to use timer_setup()
ide: Convert timers to use timer_setup()
drbd: Convert timers to use timer_setup()
mailbox: Convert timers to use timer_setup()
crypto: Convert timers to use timer_setup()
drivers/pcmcia: omap1: Fix error in automated timer conversion
ARM: footbridge: Fix typo in timer conversion
drivers/sgi-xp: Convert timers to use timer_setup()
drivers/pcmcia: Convert timers to use timer_setup()
drivers/memstick: Convert timers to use timer_setup()
drivers/macintosh: Convert timers to use timer_setup()
hwrng/xgene-rng: Convert timers to use timer_setup()
auxdisplay: Convert timers to use timer_setup()
sparc/led: Convert timers to use timer_setup()
mips: ip22/32: Convert timers to use timer_setup()
...
__getnstimeofday() is a rather odd interface, with a number of quirks:
- The caller may come from NMI context, but the implementation is not NMI safe,
one way to get there from NMI is
NMI handler:
something bad
panic()
kmsg_dump()
pstore_dump()
pstore_record_init()
__getnstimeofday()
- The calling conventions are different from any other timekeeping functions,
to deal with returning an error code during suspended timekeeping.
Address the above issues by using a completely different method to get the
time: ktime_get_real_fast_ns() is NMI safe and has a reasonable behavior
when timekeeping is suspended: it returns the time at which it got
suspended. As Thomas Gleixner explained, this is safe, as
ktime_get_real_fast_ns() does not call into the clocksource driver that
might be suspended.
The result can easily be transformed into a timespec structure. Since
ktime_get_real_fast_ns() was not exported to modules, add the export.
The pstore behavior for the suspended case changes slightly, as it now
stores the timestamp at which timekeeping was suspended instead of storing
a zero timestamp.
This change is not addressing y2038-safety, that's subject to a more
complex follow up patch.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Colin Cross <ccross@android.com>
Link: https://lkml.kernel.org/r/20171110152530.1926955-1-arnd@arndb.de
IS_ERR() macro it is already including unlikely().
Signed-off-by: Hirofumi Nakagawa <nklabs@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 68c4a4f8ab, with
various conflict clean-ups.
The capability check required too much privilege compared to simple DAC
controls. A system builder was forced to have crash handler processes
run with CAP_SYSLOG which would give it the ability to read (and wipe)
the _current_ dmesg, which is much more access than being given access
only to the historical log stored in pstorefs.
With the prior commit to make the root directory 0750, the files are
protected by default but a system builder can now opt to give access
to a specific group (via chgrp on the pstorefs root directory) without
being forced to also give away CAP_SYSLOG.
Suggested-by: Nick Kralevich <nnk@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Petr Mladek <pmladek@suse.cz>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Currently only DMESG and CONSOLE record types are protected, and it isn't
obvious that they are using a capability check. Instead switch to explicit
root directory mode of 0750 to keep files private by default. This will
allow the removal of the capability check, which was non-obvious and
forces a process to have possibly too much privilege when simple post-boot
chgrp for readers would be possible without it.
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Pull ->s_options removal from Al Viro:
"Preparations for fsmount/fsopen stuff (coming next cycle). Everything
gets moved to explicit ->show_options(), killing ->s_options off +
some cosmetic bits around fs/namespace.c and friends. Basically, the
stuff needed to work with fsmount series with minimum of conflicts
with other work.
It's not strictly required for this merge window, but it would reduce
the PITA during the coming cycle, so it would be nice to have those
bits and pieces out of the way"
* 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
isofs: Fix isofs_show_options()
VFS: Kill off s_options and helpers
orangefs: Implement show_options
9p: Implement show_options
isofs: Implement show_options
afs: Implement show_options
affs: Implement show_options
befs: Implement show_options
spufs: Implement show_options
bpf: Implement show_options
ramfs: Implement show_options
pstore: Implement show_options
omfs: Implement show_options
hugetlbfs: Implement show_options
VFS: Don't use save/replace_mount_options if not using generic_show_options
VFS: Provide empty name qstr
VFS: Make get_filesystem() return the affected filesystem
VFS: Clean up whitespace in fs/namespace.c and fs/super.c
Provide a function to create a NUL-terminated string from unterminated data
Implement the show_options superblock op for pstore as part of a bid to get
rid of s_options and generic_show_options() to make it easier to implement
a context-based mount where the mount options can be passed individually
over a file descriptor.
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Kees Cook <keescook@chromium.org>
cc: Anton Vorontsov <anton@enomsg.org>
cc: Colin Cross <ccross@android.com>
cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Use memdup_user() helper instead of open-coding to simplify the code.
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
The current time will be initially available in the record->time field
for all pstore_read() and pstore_write() calls. Backends can either
update the field during read(), or use the field during write() instead
of fetching time themselves.
Signed-off-by: Kees Cook <keescook@chromium.org>
In preparation for setting timestamps in the pstore core, create a common
initializer routine, instead of using static initializers.
Signed-off-by: Kees Cook <keescook@chromium.org>
If a backend does not correctly iterate through its records, pstore will
get stuck loading entries. Detect this with a large record count, and
announce if we ever hit the limit. This will let future backend reading
bugs less annoying to debug. Additionally adjust the error about
pstore_mkfile() failing.
Signed-off-by: Kees Cook <keescook@chromium.org>
When the "if (record->size <= 0)" test is true in
pstore_get_backend_records() it's pretty clear that nobody holds a
reference to the allocated pstore_record, yet we don't free it.
Let's free it.
Fixes: 2a2b0acf76 ("pstore: Allocate records on heap instead of stack")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
commit 9abdcccc3d ("pstore: Extract common arguments into structure")
moved record decompression to function. decompress_record() gets
called without checking type and compressed flag. Warning will be
reported if data is uncompressed. Pstore type PSTORE_TYPE_PPC_OPAL,
PSTORE_TYPE_PPC_COMMON doesn't contain compressed data and warning get
printed part of dmesg.
Partial dmesg log:
[ 35.848914] pstore: ignored compressed record type 6
[ 35.848927] pstore: ignored compressed record type 8
Above warning should not get printed as it is known that data won't be
compressed for above type and it is valid condition.
This patch returns if data is not compressed and print warning only if
data is compressed and type is not PSTORE_TYPE_DMESG.
Reported-by: Anton Blanchard <anton@au1.ibm.com>
Signed-off-by: Ankit Kumar <ankit@linux.vnet.ibm.com>
Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Fixes: 9abdcccc3d ("pstore: Extract common arguments into structure")
Cc: stable@vger.kernel.org
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Merge tag 'hwparam-20170420' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs
Pull hw lockdown support from David Howells:
"Annotation of module parameters that configure hardware resources
including ioports, iomem addresses, irq lines and dma channels.
This allows a future patch to prohibit the use of such module
parameters to prevent that hardware from being abused to gain access
to the running kernel image as part of locking the kernel down under
UEFI secure boot conditions.
Annotations are made by changing:
module_param(n, t, p)
module_param_named(n, v, t, p)
module_param_array(n, t, m, p)
to:
module_param_hw(n, t, hwtype, p)
module_param_hw_named(n, v, t, hwtype, p)
module_param_hw_array(n, t, hwtype, m, p)
where the module parameter refers to a hardware setting
hwtype specifies the type of the resource being configured. This can
be one of:
ioport Module parameter configures an I/O port
iomem Module parameter configures an I/O mem address
ioport_or_iomem Module parameter could be either (runtime set)
irq Module parameter configures an I/O port
dma Module parameter configures a DMA channel
dma_addr Module parameter configures a DMA buffer address
other Module parameter configures some other value
Note that the hwtype is compile checked, but not currently stored (the
lockdown code probably won't require it). It is, however, there for
future use.
A bonus is that the hwtype can also be used for grepping.
The intention is for the kernel to ignore or reject attempts to set
annotated module parameters if lockdown is enabled. This applies to
options passed on the boot command line, passed to insmod/modprobe or
direct twiddling in /sys/module/ parameter files.
The module initialisation then needs to handle the parameter not being
set, by (1) giving an error, (2) probing for a value or (3) using a
reasonable default.
What I can't do is just reject a module out of hand because it may
take a hardware setting in the module parameters. Some important
modules, some ipmi stuff for instance, both probe for hardware and
allow hardware to be manually specified; if the driver is aborts with
any error, you don't get any ipmi hardware.
Further, trying to do this entirely in the module initialisation code
doesn't protect against sysfs twiddling.
[!] Note that in and of itself, this series of patches should have no
effect on the the size of the kernel or code execution - that is
left to a patch in the next series to effect. It does mark
annotated kernel parameters with a KERNEL_PARAM_FL_HWPARAM flag in
an already existing field"
* tag 'hwparam-20170420' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: (38 commits)
Annotate hardware config module parameters in sound/pci/
Annotate hardware config module parameters in sound/oss/
Annotate hardware config module parameters in sound/isa/
Annotate hardware config module parameters in sound/drivers/
Annotate hardware config module parameters in fs/pstore/
Annotate hardware config module parameters in drivers/watchdog/
Annotate hardware config module parameters in drivers/video/
Annotate hardware config module parameters in drivers/tty/
Annotate hardware config module parameters in drivers/staging/vme/
Annotate hardware config module parameters in drivers/staging/speakup/
Annotate hardware config module parameters in drivers/staging/media/
Annotate hardware config module parameters in drivers/scsi/
Annotate hardware config module parameters in drivers/pcmcia/
Annotate hardware config module parameters in drivers/pci/hotplug/
Annotate hardware config module parameters in drivers/parport/
Annotate hardware config module parameters in drivers/net/wireless/
Annotate hardware config module parameters in drivers/net/wan/
Annotate hardware config module parameters in drivers/net/irda/
Annotate hardware config module parameters in drivers/net/hamradio/
Annotate hardware config module parameters in drivers/net/ethernet/
...
Lockdep complains about a possible deadlock between mount and unlink
(which is technically impossible), but fixing this improves possible
future multiple-backend support, and keeps locking in the right order.
The lockdep warning could be triggered by unlinking a file in the
pstore filesystem:
-> #1 (&sb->s_type->i_mutex_key#14){++++++}:
lock_acquire+0xc9/0x220
down_write+0x3f/0x70
pstore_mkfile+0x1f4/0x460
pstore_get_records+0x17a/0x320
pstore_fill_super+0xa4/0xc0
mount_single+0x89/0xb0
pstore_mount+0x13/0x20
mount_fs+0xf/0x90
vfs_kern_mount+0x66/0x170
do_mount+0x190/0xd50
SyS_mount+0x90/0xd0
entry_SYSCALL_64_fastpath+0x1c/0xb1
-> #0 (&psinfo->read_mutex){+.+.+.}:
__lock_acquire+0x1ac0/0x1bb0
lock_acquire+0xc9/0x220
__mutex_lock+0x6e/0x990
mutex_lock_nested+0x16/0x20
pstore_unlink+0x3f/0xa0
vfs_unlink+0xb5/0x190
do_unlinkat+0x24c/0x2a0
SyS_unlinkat+0x16/0x30
entry_SYSCALL_64_fastpath+0x1c/0xb1
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&sb->s_type->i_mutex_key#14);
lock(&psinfo->read_mutex);
lock(&sb->s_type->i_mutex_key#14);
lock(&psinfo->read_mutex);
Reported-by: Marta Lofstedt <marta.lofstedt@intel.com>
Reported-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Since the vmalloc code has been removed from write_pmsg() in the commit
"5bf6d1b pstore/pmsg: drop bounce buffer", remove the unused header
vmalloc.h.
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
When the kernel is running in secure boot mode, we lock down the kernel to
prevent userspace from modifying the running kernel image. Whilst this
includes prohibiting access to things like /dev/mem, it must also prevent
access by means of configuring driver modules in such a way as to cause a
device to access or modify the kernel image.
To this end, annotate module_param* statements that refer to hardware
configuration and indicate for future reference what type of parameter they
specify. The parameter parser in the core sees this information and can
skip such parameters with an error message if the kernel is locked down.
The module initialisation then runs as normal, but just sees whatever the
default values for those parameters is.
Note that we do still need to do the module initialisation because some
drivers have viable defaults set in case parameters aren't specified and
some drivers support automatic configuration (e.g. PNP or PCI) in addition
to manually coded parameters.
This patch annotates drivers in fs/pstore/.
Suggested-by: Alan Cox <gnomes@lxorguk.ukuu.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
cc: Anton Vorontsov <anton@enomsg.org>
cc: Colin Cross <ccross@android.com>
cc: Tony Luck <tony.luck@intel.com>
Nothing actually uses write_user_compat() currently, but there is no
reason to reuse the dmesg buffer. Instead, just allocate a new record
buffer, copy in from userspace, and pass it to write() as normal.
Signed-off-by: Kees Cook <keescook@chromium.org>
Now that write() and write_buf() are functionally identical, this removes
write_buf(), and renames write_buf_user() to write_user(). Additionally
adds sanity-checks for pstore_info's declared functions and flags at
registration time.
Signed-off-by: Kees Cook <keescook@chromium.org>
Removes argument list in favor of pstore record, though the user buffer
remains passed separately since it must carry the __user annotation.
Signed-off-by: Kees Cook <keescook@chromium.org>
As with the other API updates, this removes the long argument list in favor
of passing a single pstore recaord.
Signed-off-by: Kees Cook <keescook@chromium.org>
This removes the argument list for the erase() callback and replaces it
with a pointer to the backend record details to be removed.
Signed-off-by: Kees Cook <keescook@chromium.org>
This switches the inode-private data from carrying duplicate metadata to
keeping the record passed in during pstore_mkfile().
Signed-off-by: Kees Cook <keescook@chromium.org>
In preparation for handling records off to pstore_mkfile(), allocate the
record instead of reusing stack. This still always frees the record,
though, since pstore_mkfile() isn't yet keeping it.
Signed-off-by: Kees Cook <keescook@chromium.org>
pstore_mkfile() shouldn't have to memcpy the record contents. It can use
the existing copy instead. This adjusts the allocation lifetime management
and renames the contents variable from "data" to "buf" to assist moving to
struct pstore_record in the future.
Signed-off-by: Kees Cook <keescook@chromium.org>
Currently, pstore_mkfile() performs a memcpy() of the record contents,
so it can live anywhere. However, this is needlessly wasteful. In
preparation of pstore_mkfile() keeping the record contents, always
allocate a buffer for the contents.
Signed-off-by: Kees Cook <keescook@chromium.org>
Similar to the pstore_info read() callback, there were too many arguments.
This switches to the new struct pstore_record pointer instead. This adds
"reason" and "part" to the record structure as well.
Signed-off-by: Kees Cook <keescook@chromium.org>
The argument list for the pstore_read() interface is unwieldy. This changes
passes the new struct pstore_record instead. The erst backend was already
doing something similar internally.
Signed-off-by: Kees Cook <keescook@chromium.org>
The read/mkfile pair pass the same arguments and should be cleared
between calls. Move to a structure and wipe it after every loop.
Signed-off-by: Kees Cook <keescook@chromium.org>
Uncommon errors are better to get reported to dmesg so developers can
more easily figure out why pstore is unhappy with a backend attempting
to register.
Signed-off-by: Kees Cook <keescook@chromium.org>
Technically, it might be possible for struct pstore_info to go out of
scope after the module_put(), so report the backend name first.
Signed-off-by: Kees Cook <keescook@chromium.org>
When built as a module and running with update_ms >= 0, pstore will Oops
during module unload since the work timer is still running. This makes sure
the worker is stopped before unloading.
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
The per-prz spinlock should be using the dynamic initializer so that
lockdep can correctly track it. Without this, under lockdep, we get a
warning at boot that the lock is in non-static memory.
Fixes: 109704492e ("pstore: Make spinlock per zone instead of global")
Fixes: 76d5692a58 ("pstore: Correctly initialize spinlock and flags")
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
The references of pstore_zbackend structures are stored into the
pointer zbackend of type struct pstore_zbackend. The pointer zbackend
can be made const as it is only dereferenced. After making this change
the pstore_zbackend structures whose references are stored into the
pointer zbackend can be made const too.
File size before:
text data bss dec hex filename
4817 541 172 5530 159a fs/pstore/platform.o
File size after:
text data bss dec hex filename
4865 477 172 5514 158a fs/pstore/platform.o
Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Update fs/pstore and fs/squashfs to use the updated functions from the
new LZ4 module.
Link: http://lkml.kernel.org/r/1486321748-19085-5-git-send-email-4sschmid@informatik.uni-hamburg.de
Signed-off-by: Sven Schmidt <4sschmid@informatik.uni-hamburg.de>
Cc: Bongkyu Kim <bongkyu.kim@lge.com>
Cc: Rui Salvaterra <rsalvaterra@gmail.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: David S. Miller <davem@davemloft.net>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Instead of needing additional checks in callers for unallocated przs,
perform the check in the walker, which gives us a more universal way to
handle the situation.
Signed-off-by: Kees Cook <keescook@chromium.org>
We'll OOPS in ramoops_get_next_prz() if the platform didn't ask for any
ftrace zones (i.e., cxt->fprzs will be NULL). Let's just skip this
entire FTRACE section if there's no 'fprzs'.
Regression seen on a coreboot/depthcharge-based Chromebook.
Fixes: 2fbea82bbb ("pstore: Merge per-CPU ftrace records into one")
Cc: Joel Fernandes <joelaf@google.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
- Add additional checks for bad platform data
- Remove bounce buffer in console writer
- Protect read/unlink race with a mutex
- Correctly give up during dump locking failures
- Increase ftrace bandwidth by splitting ftrace buffers per CPU
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Merge tag 'pstore-v4.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull pstore updates from Kees Cook:
"Improvements and fixes to pstore subsystem:
- add additional checks for bad platform data
- remove bounce buffer in console writer
- protect read/unlink race with a mutex
- correctly give up during dump locking failures
- increase ftrace bandwidth by splitting ftrace buffers per CPU"
* tag 'pstore-v4.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
ramoops: add pdata NULL check to ramoops_probe
pstore: Convert console write to use ->write_buf
pstore: Protect unlink with read_mutex
pstore: Use global ftrace filters for function trace filtering
ftrace: Provide API to use global filtering for ftrace ops
pstore: Clarify context field przs as dprzs
pstore: improve error report for failed setup
pstore: Merge per-CPU ftrace records into one
pstore: Add ftrace timestamp counter
ramoops: Split ftrace buffer space into per-CPU zones
pstore: Make ramoops_init_przs generic for other prz arrays
pstore: Allow prz to control need for locking
pstore: Warn on PSTORE_TYPE_PMSG using deprecated function
pstore: Make spinlock per zone instead of global
pstore: Actually give up during locking failure
This adds a check for a NULL platform data, which should only be possible
if a driver incorrectly sets up a probe request without also having defined
the platform_data structure. This is based on a patch from Geliang Tang.
Signed-off-by: Kees Cook <keescook@chromium.org>
Maybe I'm missing something, but I don't know why it needs to copy the
input buffer to psinfo->buf and then write. Instead we can write the
input buffer directly. The only implementation that supports console
message (i.e. ramoops) already does it for ftrace messages.
For the upcoming virtio backend driver, it needs to protect psinfo->buf
overwritten from console messages. If it could use ->write_buf method
instead of ->write, the problem will be solved easily.
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
When update_ms is set, pstore_get_records() will be called when there's
a new entry. But unlink can be called at the same time and might
contend with the open-read-close loop. Depending on the implementation
of platform driver, it may be safe or not. But I think it'd be better
to protect those race in the first place.
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Currently, pstore doesn't have any filters setup for function tracing.
This has the associated overhead and may not be useful for users looking
for tracing specific set of functions.
ftrace's regular function trace filtering is done writing to
tracing/set_ftrace_filter however this is not available if not requested.
In order to be able to use this feature, the support to request global
filtering introduced earlier in the series should be requested before
registering the ftrace ops. Here we do the same.
Signed-off-by: Joel Fernandes <joelaf@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Since "przs" (persistent ram zones) is a general name in the code now, so
rename the Oops-dump zones to dprzs from przs.
Based on a patch from Nobuhiro Iwamatsu.
Signed-off-by: Kees Cook <keescook@chromium.org>
When setting ramoops record sizes, sometimes it's not clear which
parameters contributed to the allocation failure. This adds a per-zone
name and expands the failure reports.
Signed-off-by: Kees Cook <keescook@chromium.org>
Up until this patch, each of the per CPU ftrace buffers appear as a
separate ftrace-ramoops-N file. In this patch we merge all the zones into
one and populate a single ftrace-ramoops-0 file.
Signed-off-by: Joel Fernandes <joelaf@google.com>
[kees: clarified variables names, added -ENOMEM handling]
Signed-off-by: Kees Cook <keescook@chromium.org>
In preparation for merging the per CPU buffers into one buffer when
we retrieve the pstore ftrace data, we store the timestamp as a
counter in the ftrace pstore record. We store the CPU number as well
if !PSTORE_CPU_IN_IP, in this case we shift the counter and may lose
ordering there but we preserve the same record size. The timestamp counter
is also racy, and not doing any locking or synchronization here results
in the benefit of lower overhead. Since we don't care much here for exact
ordering of function traces across CPUs, we don't synchronize and may lose
some counter updates but I'm ok with that.
Using trace_clock() results in much lower performance so avoid using it
since we don't want accuracy in timestamp and need a rough ordering to
perform merge.
Signed-off-by: Joel Fernandes <joelaf@google.com>
[kees: updated commit message, added comments]
Signed-off-by: Kees Cook <keescook@chromium.org>
If the RAMOOPS_FLAG_FTRACE_PER_CPU flag is passed to ramoops pdata, split
the ftrace space into multiple zones depending on the number of CPUs.
This speeds up the performance of function tracing by about 280% in my
tests as we avoid the locking. The trade off being lesser space available
per CPU. Let the ramoops user decide which option they want based on pdata
flag.
Signed-off-by: Joel Fernandes <joelaf@google.com>
[kees: added max_ftrace_cnt to track size, added DT logic and docs]
Signed-off-by: Kees Cook <keescook@chromium.org>
Currently ramoops_init_przs() is hard wired only for panic dump zone
array. In preparation for the ftrace zone array (one zone per-cpu) and pmsg
zone array, make the function more generic to be able to handle this case.
Heavily based on similar work from Joel Fernandes.
Signed-off-by: Kees Cook <keescook@chromium.org>
In preparation of not locking at all for certain buffers depending on if
there's contention, make locking optional depending on the initialization
of the prz.
Signed-off-by: Joel Fernandes <joelaf@google.com>
[kees: moved locking flag into prz instead of via caller arguments]
Signed-off-by: Kees Cook <keescook@chromium.org>
