CVE-2022-48847

HIGH EPSS 14.8%
Published Jul 16, 20241y ago · Modified Jun 17, 20262w ago
7.8 CVSS 3.1
High
Find Similar
Published Jul 16, 2024 1y ago
Last Modified Jun 17, 2026 2w ago

Description

In the Linux kernel, the following vulnerability has been resolved: watch_queue: Fix filter limit check 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)

CVSS Details

Base Score
7.8
Exploitability
1.8
Impact
5.9
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality High
Integrity High
Availability High

Threat Intelligence

EPSS Exploit Probability
14.8% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 1

CWE-787 Out-of-bounds Write Memory Safety

Affected Products 3

VendorProductVersionRange
linuxlinux_kernel*≥5.8  –  <5.10.106
linuxlinux_kernel*≥5.11  –  <5.15.29
linuxlinux_kernel*≥5.16  –  <5.16.15

References 4

  • git.kernel.org https://git.kernel.org/stable/c/1b09f28f70a5046acd64138075ae3f095238b045
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/648895da69ced90ca770fd941c3d9479a9d72c16
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/b36588ebbcef74583824c08352e75838d6fb4ff2
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/c993ee0f9f81caf5767a50d1faeba39a0dc82af2
    Patch

Remediation

  • git.kernel.org https://git.kernel.org/stable/c/1b09f28f70a5046acd64138075ae3f095238b045
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/648895da69ced90ca770fd941c3d9479a9d72c16
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/b36588ebbcef74583824c08352e75838d6fb4ff2
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/c993ee0f9f81caf5767a50d1faeba39a0dc82af2
    Patch