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David Howells 1b09f28f70 watch_queue: Fix filter limit check
commit c993ee0f9f upstream.

In watch_queue_set_filter(), there are a couple of places where we check
that the filter type value does not exceed what the type_filter bitmap
can hold.  One place calculates the number of bits by:

   if (tf[i].type >= sizeof(wfilter->type_filter) * 8)

which is fine, but the second does:

   if (tf[i].type >= sizeof(wfilter->type_filter) * BITS_PER_LONG)

which is not.  This can lead to a couple of out-of-bounds writes due to
a too-large type:

 (1) __set_bit() on wfilter->type_filter
 (2) Writing more elements in wfilter->filters[] than we allocated.

Fix this by just using the proper WATCH_TYPE__NR instead, which is the
number of types we actually know about.

The bug may cause an oops looking something like:

  BUG: KASAN: slab-out-of-bounds in watch_queue_set_filter+0x659/0x740
  Write of size 4 at addr ffff88800d2c66bc by task watch_queue_oob/611
  ...
  Call Trace:
   <TASK>
   dump_stack_lvl+0x45/0x59
   print_address_description.constprop.0+0x1f/0x150
   ...
   kasan_report.cold+0x7f/0x11b
   ...
   watch_queue_set_filter+0x659/0x740
   ...
   __x64_sys_ioctl+0x127/0x190
   do_syscall_64+0x43/0x90
   entry_SYSCALL_64_after_hwframe+0x44/0xae

  Allocated by task 611:
   kasan_save_stack+0x1e/0x40
   __kasan_kmalloc+0x81/0xa0
   watch_queue_set_filter+0x23a/0x740
   __x64_sys_ioctl+0x127/0x190
   do_syscall_64+0x43/0x90
   entry_SYSCALL_64_after_hwframe+0x44/0xae

  The buggy address belongs to the object at ffff88800d2c66a0
   which belongs to the cache kmalloc-32 of size 32
  The buggy address is located 28 bytes inside of
   32-byte region [ffff88800d2c66a0, ffff88800d2c66c0)

Fixes: c73be61ced ("pipe: Add general notification queue support")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-16 14:23:44 +01:00
arch ARM: fix Thumb2 regression with Spectre BHB 2022-03-16 14:23:44 +01:00
block block-map: add __GFP_ZERO flag for alloc_page in function bio_copy_kern 2022-03-08 19:12:31 +01:00
certs certs: Add support for using elliptic curve keys for signing modules 2021-08-23 19:55:42 +03:00
crypto crypto: api - Move cryptomgr soft dependency into algapi 2022-02-11 09:10:26 +01:00
Documentation swiotlb: rework "fix info leak with DMA_FROM_DEVICE" 2022-03-16 14:23:43 +01:00
drivers net/mlx5: Fix offloading with ESWITCH_IPV4_TTL_MODIFY_ENABLE 2022-03-16 14:23:43 +01:00
fs fuse: fix pipe buffer lifetime for direct_io 2022-03-16 14:23:42 +01:00
include watch_queue: Fix filter limit check 2022-03-16 14:23:44 +01:00
init init: make unknown command line param message clearer 2021-11-18 19:17:11 +01:00
ipc ipc/sem: do not sleep with a spin lock held 2022-02-08 18:34:03 +01:00
kernel watch_queue: Fix filter limit check 2022-03-16 14:23:44 +01:00
lib lib/iov_iter: initialize "flags" in new pipe_buffer 2022-02-23 12:03:20 +01:00
LICENSES LICENSES/dual/CC-BY-4.0: Git rid of "smart quotes" 2021-07-15 06:31:24 -06:00
mm memfd: fix F_SEAL_WRITE after shmem huge page allocated 2022-03-08 19:12:48 +01:00
net ipv6: prevent a possible race condition with lifetimes 2022-03-16 14:23:41 +01:00
samples samples: bpf: Fix 'unknown warning group' build warning on Clang 2022-01-27 11:03:29 +01:00
scripts kconfig: fix failing to generate auto.conf 2022-02-23 12:03:20 +01:00
security selinux: fix misuse of mutex_is_locked() 2022-03-02 11:47:48 +01:00
sound ASoC: cs4265: Fix the duplicated control name 2022-03-08 19:12:47 +01:00
tools selftests/memfd: clean up mapping in mfd_fail_write 2022-03-16 14:23:42 +01:00
usr usr/include/Makefile: add linux/nfc.h to the compile-test coverage 2022-02-01 17:27:15 +01:00
virt KVM: Fix lockdep false negative during host resume 2022-03-16 14:23:40 +01:00
.clang-format clang-format: Update with the latest for_each macro list 2021-05-12 23:32:39 +02:00
.cocciconfig
.get_maintainer.ignore
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: ignore only top-level modules.builtin 2021-05-02 00:43:35 +09:00
.mailmap mailmap: add Andrej Shadura 2021-10-18 20:22:03 -10:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Move Daniel Drake to credits 2021-09-21 08:34:58 +03:00
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 MAINTAINERS: adjust file entry for of_net.c after movement 2022-03-08 19:12:53 +01:00
Makefile Linux 5.15.28 2022-03-11 12:22:37 +01:00
README

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.