CVSS3
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
AI Score
Confidence
High
EPSS
Percentile
5.1%
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)
OS | Version | Architecture | Package | Version | Filename |
---|---|---|---|---|---|
ubuntu | 20.04 | noarch | linux-intel-iotg-5.15 | < any | UNKNOWN |
git.kernel.org/linus/c993ee0f9f81caf5767a50d1faeba39a0dc82af2 (5.17-rc8)
git.kernel.org/stable/c/1b09f28f70a5046acd64138075ae3f095238b045
git.kernel.org/stable/c/648895da69ced90ca770fd941c3d9479a9d72c16
git.kernel.org/stable/c/b36588ebbcef74583824c08352e75838d6fb4ff2
git.kernel.org/stable/c/c993ee0f9f81caf5767a50d1faeba39a0dc82af2
launchpad.net/bugs/cve/CVE-2022-48847
nvd.nist.gov/vuln/detail/CVE-2022-48847
security-tracker.debian.org/tracker/CVE-2022-48847
www.cve.org/CVERecord?id=CVE-2022-48847