CVE-2024-50067
- Source
- https://nvd.nist.gov/vuln/detail/CVE-2024-50067
- Import Source
- https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2024-50067.json
- JSON Data
- https://api.osv.dev/v1/vulns/CVE-2024-50067
- Downstream
- Related
- Published
- 2024-10-28T00:57:05Z
- Modified
- 2025-10-15T17:39:12.490239Z
- Severity
-
- 7.8 (High) CVSS_V3 - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H CVSS Calculator
- Summary
- uprobe: avoid out-of-bounds memory access of fetching args
- Details
-
In the Linux kernel, the following vulnerability has been resolved:
uprobe: avoid out-of-bounds memory access of fetching args
Uprobe needs to fetch args into a percpu buffer, and then copy to ring buffer to avoid non-atomic context problem.
Sometimes user-space strings, arrays can be very large, but the size of percpu buffer is only page size. And storetraceargs() won't check whether these data exceeds a single page or not, caused out-of-bounds memory access.
It could be reproduced by following steps: 1. build kernel with CONFIG_KASAN enabled 2. save follow program as test.c
\#include <stdio.h> \#include <stdlib.h> \#include <string.h> // If string length large than MAX_STRING_SIZE, the fetch_store_strlen() // will return 0, cause __get_data_size() return shorter size, and // store_trace_args() will not trigger out-of-bounds access. // So make string length less than 4096. \#define STRLEN 4093 void generate_string(char *str, int n) { int i; for (i = 0; i < n; ++i) { char c = i % 26 + 'a'; str[i] = c; } str[n-1] = '\0'; } void print_string(char *str) { printf("%s\n", str); } int main() { char tmp[STRLEN]; generate_string(tmp, STRLEN); print_string(tmp); return 0; }3. compile program
gcc -o test test.cget the offset of
print_string()objdump -t test | grep -w print_string 0000000000401199 g F .text 000000000000001b print_stringconfigure uprobe with offset 0x1199
off=0x1199 cd /sys/kernel/debug/tracing/ echo "p /root/test:${off} arg1=+0(%di):ustring arg2=\$comm arg3=+0(%di):ustring" > uprobe_events echo 1 > events/uprobes/enable echo 1 > tracing_on
6. run
test, and kasan will report error.BUG: KASAN: use-after-free in strncpyfromuser+0x1d6/0x1f0 Write of size 8 at addr ffff88812311c004 by task test/499CPU: 0 UID: 0 PID: 499 Comm: test Not tainted 6.12.0-rc3+ #18 Hardware name: Red Hat KVM, BIOS 1.16.0-4.al8 04/01/2014 Call Trace: <TASK> dumpstacklvl+0x55/0x70 printaddressdescription.constprop.0+0x27/0x310 kasanreport+0x10f/0x120 ? strncpyfromuser+0x1d6/0x1f0 strncpyfromuser+0x1d6/0x1f0 ? rmqueue.constprop.0+0x70d/0x2ad0 processfetchinsn+0xb26/0x1470 ? pfxprocessfetchinsn+0x10/0x10 ? rawspinlock+0x85/0xe0 ? _pfxrawspinlock+0x10/0x10 ? pteoffsetmap+0x1f/0x2d0 ? unwindnextframe+0xc5f/0x1f80 ? archstackwalk+0x68/0xf0 ? isbpftextaddress+0x23/0x30 ? kerneltextaddress.part.0+0xbb/0xd0 ? _kerneltextaddress+0x66/0xb0 ? unwindgetreturnaddress+0x5e/0xa0 ? _pfxstacktraceconsumeentry+0x10/0x10 ? archstackwalk+0xa2/0xf0 ? rawspinlockirqsave+0x8b/0xf0 ? _pfxrawspinlockirqsave+0x10/0x10 ? depotallocstack+0x4c/0x1f0 ? rawspinunlockirqrestore+0xe/0x30 ? stackdepotsaveflags+0x35d/0x4f0 ? kasansavestack+0x34/0x50 ? kasansavestack+0x24/0x50 ? mutexlock+0x91/0xe0 ? _pfxmutexlock+0x10/0x10 prepareuprobebuffer.part.0+0x2cd/0x500 uprobedispatcher+0x2c3/0x6a0 ? _pfxuprobedispatcher+0x10/0x10 ? _kasanslaballoc+0x4d/0x90 handlerchain+0xdd/0x3e0 handleswbp+0x26e/0x3d0 ? _pfxhandleswbp+0x10/0x10 ? uprobepresstepnotifier+0x151/0x1b0 irqentryexittousermode+0xe2/0x1b0 asmexcint3+0x39/0x40 RIP: 0033:0x401199 Code: 01 c2 0f b6 45 fb 88 02 83 45 fc 01 8b 45 fc 3b 45 e4 7c b7 8b 45 e4 48 98 48 8d 50 ff 48 8b 45 e8 48 01 d0 ce RSP: 002b:00007ffdf00576a8 EFLAGS: 00000206 RAX: 00007ffdf00576b0 RBX: 0000000000000000 RCX: 0000000000000ff2 RDX: 0000000000000ffc RSI: 0000000000000ffd RDI: 00007ffdf00576b0 RBP: 00007ffdf00586b0 R08: 00007feb2f9c0d20 R09: 00007feb2f9c0d20 R10: 0000000000000001 R11: 0000000000000202 R12: 0000000000401040 R13: 00007ffdf0058780 R14: 0000000000000000 R15: 0000000000000000 </TASK>
This commit enforces the buffer's maxlen less than a page-size to avoid storetraceargs() out-of-memory access.
- References
-
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- https://git.kernel.org/stable/c/0dc3ad9ad2188da7f090b3dbe4d2fcd9ae8ae64f
- https://git.kernel.org/stable/c/373b9338c9722a368925d83bc622c596896b328e
- https://git.kernel.org/stable/c/537ad4a431f6dddbf15d40d19f24bb9ee12b55cb
- https://git.kernel.org/stable/c/9e5f93788c9dd4309e75a56860a1ac44a8e117b9
Affected packages
Git / git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Affected ranges
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduceddcad1a204f72624796ae83359403898d10393b9cFixed0dc3ad9ad2188da7f090b3dbe4d2fcd9ae8ae64f
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduceddcad1a204f72624796ae83359403898d10393b9cFixed9e5f93788c9dd4309e75a56860a1ac44a8e117b9
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduceddcad1a204f72624796ae83359403898d10393b9cFixed537ad4a431f6dddbf15d40d19f24bb9ee12b55cb
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduceddcad1a204f72624796ae83359403898d10393b9cFixed373b9338c9722a368925d83bc622c596896b328e