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Manuel Ullmann cbe6c3a8f8 net: atlantic: invert deep par in pm functions, preventing null derefs
This will reset deeply on freeze and thaw instead of suspend and
resume and prevent null pointer dereferences of the uninitialized ring
0 buffer while thawing.

The impact is an indefinitely hanging kernel. You can't switch
consoles after this and the only possible user interaction is SysRq.

BUG: kernel NULL pointer dereference
RIP: 0010:aq_ring_rx_fill+0xcf/0x210 [atlantic]
aq_vec_init+0x85/0xe0 [atlantic]
aq_nic_init+0xf7/0x1d0 [atlantic]
atl_resume_common+0x4f/0x100 [atlantic]
pci_pm_thaw+0x42/0xa0

resolves in aq_ring.o to

```
0000000000000ae0 <aq_ring_rx_fill>:
{
/* ... */
 baf:	48 8b 43 08          	mov    0x8(%rbx),%rax
 		buff->flags = 0U; /* buff is NULL */
```

The bug has been present since the introduction of the new pm code in
8aaa112a57 ("net: atlantic: refactoring pm logic") and was hidden
until 8ce8427169 ("net: atlantic: changes for multi-TC support"),
which refactored the aq_vec_{free,alloc} functions into
aq_vec_{,ring}_{free,alloc}, but is technically not wrong. The
original functions just always reinitialized the buffers on S3/S4. If
the interface is down before freezing, the bug does not occur. It does
not matter, whether the initrd contains and loads the module before
thawing.

So the fix is to invert the boolean parameter deep in all pm function
calls, which was clearly intended to be set like that.

First report was on Github [1], which you have to guess from the
resume logs in the posted dmesg snippet. Recently I posted one on
Bugzilla [2], since I did not have an AQC device so far.

#regzbot introduced: 8ce8427169
#regzbot from: koo5 <kolman.jindrich@gmail.com>
#regzbot monitor: https://github.com/Aquantia/AQtion/issues/32

Fixes: 8aaa112a57 ("net: atlantic: refactoring pm logic")
Link: https://github.com/Aquantia/AQtion/issues/32 [1]
Link: https://bugzilla.kernel.org/show_bug.cgi?id=215798 [2]
Cc: stable@vger.kernel.org
Reported-by: koo5 <kolman.jindrich@gmail.com>
Signed-off-by: Manuel Ullmann <labre@posteo.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-18 13:34:36 +01:00
arch x86: 2022-04-12 14:16:33 -10:00
block for-5.18/block-2022-04-01 2022-04-01 16:20:00 -07:00
certs Kbuild updates for v5.18 2022-03-31 11:59:03 -07:00
crypto for-5.18/64bit-pi-2022-03-25 2022-03-26 12:01:35 -07:00
Documentation Networking fixes for 5.18-rc3, including fixes from wireless and 2022-04-14 11:58:19 -07:00
drivers net: atlantic: invert deep par in pm functions, preventing null derefs 2022-04-18 13:34:36 +01:00
fs for-5.18-rc2-tag 2022-04-14 10:58:27 -07:00
include ipv6: make ip6_rt_gc_expire an atomic_t 2022-04-15 14:28:50 -07:00
init Kbuild updates for v5.18 2022-03-31 11:59:03 -07:00
ipc fs: allocate inode by using alloc_inode_sb() 2022-03-22 15:57:03 -07:00
kernel - A couple of fixes to cgroup-related handling of perf events 2022-04-10 07:08:22 -10:00
lib Driver core changes for 5.18-rc2 2022-04-10 09:55:09 -10:00
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mm - Allow the compiler to optimize away unused percpu accesses and change 2022-04-10 06:56:46 -10:00
net can: isotp: stop timeout monitoring when no first frame was sent 2022-04-17 17:21:22 +02:00
samples dma-mapping updates for Linux 5.18 2022-03-29 08:50:14 -07:00
scripts hardening fixes for v5.18-rc3 2022-04-12 14:29:40 -10:00
security hardening updates for v5.18-rc1-fix1 2022-03-31 11:43:01 -07:00
sound sound fixes for 5.18-rc3 2022-04-14 11:08:12 -07:00
tools x86: 2022-04-12 14:16:33 -10:00
usr Kbuild updates for v5.18 2022-03-31 11:59:03 -07:00
virt KVM/arm64 fixes for 5.18, take #1 2022-04-08 12:30:04 -04:00
.clang-format genirq/msi: Make interrupt allocation less convoluted 2021-12-16 22:22:20 +01:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
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.mailmap mailmap: update Vasily Averin's email address 2022-04-08 14:20:36 -10:00
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Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS powerpc: Update MAINTAINERS for ibmvnic and VAS 2022-04-15 12:07:33 +01:00
Makefile Linux 5.18-rc2 2022-04-10 14:21:36 -10:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.