A mirror of the official Linux kernel repository just in case
Go to file
Alexander Shishkin 05b686b573 intel_th: msu: Fix window switching without windows
Commit 6cac7866c2 ("intel_th: msu: Add a sysfs attribute to trigger
window switch") adds a NULL pointer dereference in the case when there are
no windows allocated:

> BUG: kernel NULL pointer dereference, address: 0000000000000000
> #PF: supervisor read access in kernel mode
> #PF: error_code(0x0000) - not-present page
> PGD 0 P4D 0
> Oops: 0000 1 SMP
> CPU: 5 PID: 1110 Comm: bash Not tainted 5.5.0-rc1+ #1
> RIP: 0010:msc_win_switch+0xa/0x80 [intel_th_msu]
> Call Trace:
> ? win_switch_store+0x9b/0xc0 [intel_th_msu]
> dev_attr_store+0x17/0x30
> sysfs_kf_write+0x3e/0x50
> kernfs_fop_write+0xda/0x1b0
> __vfs_write+0x1b/0x40
> vfs_write+0xb9/0x1a0
> ksys_write+0x67/0xe0
> __x64_sys_write+0x1a/0x20
> do_syscall_64+0x57/0x1d0
> entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fix that by disallowing window switching with multiwindow buffers without
windows.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Fixes: 6cac7866c2 ("intel_th: msu: Add a sysfs attribute to trigger window switch")
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reported-by: Ammy Yi <ammy.yi@intel.com>
Tested-by: Ammy Yi <ammy.yi@intel.com>
Cc: stable@vger.kernel.org # v5.2+
Link: https://lore.kernel.org/r/20191217115527.74383-5-alexander.shishkin@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-12-17 15:45:59 +01:00
arch RISC-V updates for v5.5-rc2 2019-12-15 12:27:31 -08:00
block for-linus-20191212 2019-12-13 14:27:19 -08:00
certs certs: Add wrapper function to check blacklisted binary hash 2019-11-12 12:25:50 +11:00
crypto treewide: Use sizeof_field() macro 2019-12-09 10:36:44 -08:00
Documentation SCSI fixes on 20191214 2019-12-14 12:51:57 -08:00
drivers intel_th: msu: Fix window switching without windows 2019-12-17 15:45:59 +01:00
fs Merge branch 'remove-ksys-mount-dup' of git://git.kernel.org/pub/scm/linux/kernel/git/brodo/linux 2019-12-15 11:36:12 -08:00
include Pull request for 5.5-rc2 2019-12-15 14:58:13 -08:00
init fs: remove ksys_dup() 2019-12-12 19:00:36 +01:00
ipc treewide: Use sizeof_field() macro 2019-12-09 10:36:44 -08:00
kernel treewide conversion from FIELD_SIZEOF() to sizeof_field() 2019-12-13 14:02:12 -08:00
lib lib: raid6: fix awk build warnings 2019-12-09 18:55:03 +01:00
LICENSES LICENSES: Rename other to deprecated 2019-05-03 06:34:32 -06:00
mm Merge branch 'akpm' (patches from Andrew) 2019-12-05 09:46:26 -08:00
net io_uring-5.5-20191212 2019-12-13 14:24:54 -08:00
samples samples/bpf: Fix broken xdp_rxq_info due to map order assumptions 2019-12-04 17:54:15 -08:00
scripts pr_warning() removal for 5.5 2019-12-09 11:48:21 -08:00
security treewide: Use sizeof_field() macro 2019-12-09 10:36:44 -08:00
sound sound fixes for 5.5-rc2 2019-12-13 14:40:38 -08:00
tools Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-12-08 13:28:11 -08:00
usr arch: sembuf.h: make uapi asm/sembuf.h self-contained 2019-12-04 19:44:14 -08:00
virt KVM: Fix jump label out_free_* in kvm_init() 2019-11-23 11:29:17 +01:00
.clang-format clang-format: Update with the latest for_each macro list 2019-08-31 10:00:51 +02:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore modpost: dump missing namespaces into a single modules.nsdeps file 2019-11-11 20:10:01 +09:00
.mailmap Update mailmap info for Steve Wise 2019-12-09 13:49:25 -05:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS Linux 5.4-rc4 2019-10-29 04:43:29 -06:00
Kbuild kbuild: do not descend to ./Kbuild when cleaning 2019-08-21 21:03:58 +09:00
Kconfig docs: kbuild: convert docs to ReST and rename to *.rst 2019-06-14 14:21:21 -06:00
MAINTAINERS overlayfs fixes for 5.5-rc2 2019-12-14 11:13:54 -08:00
Makefile Linux 5.5-rc2 2019-12-15 15:16:08 -08:00
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.