Description

In the Linux kernel, the following vulnerability has been resolved:

jfs: Fix uninit-value access of new_ea in ea_buffer

syzbot reports that lzo1x_1_do_compress is using uninit-value:

=====================================================
BUG: KMSAN: uninit-value in lzo1x_1_do_compress+0x19f9/0x2510 lib/lzo/lzo1x_compress.c:178

...

Uninit was stored to memory at:
ea_put fs/jfs/xattr.c:639 [inline]

...

Local variable ea_buf created at:
__jfs_setxattr+0x5d/0x1ae0 fs/jfs/xattr.c:662
__jfs_xattr_set+0xe6/0x1f0 fs/jfs/xattr.c:934

=====================================================

The reason is ea_buf->new_ea is not initialized properly.

Fix this by using memset to empty its content at the beginning
in ea_get().

Classification

CVE ID: CVE-2024-49900

CVSS Base Severity: HIGH

CVSS Base Score: 7.1

CVSS Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

Affected Products

Vendor: Linux

Product: Linux

Exploit Prediction Scoring System (EPSS)

EPSS Score: 0.03% (probability of being exploited)

EPSS Percentile: 6.36% (scored less or equal to compared to others)

EPSS Date: 2025-06-02 (when was this score calculated)

Stakeholder-Specific Vulnerability Categorization (SSVC)

SSVC Exploitation: none

SSVC Technical Impact: partial

SSVC Automatable: false

References

https://nvd.nist.gov/vuln/detail/CVE-2024-49900
https://git.kernel.org/stable/c/7b24d41d47a6805c45378debf8bd115675d41da8
https://git.kernel.org/stable/c/dac398ed272a378d2f42ac68ae408333a51baf52
https://git.kernel.org/stable/c/8b1dcf25c26d42e4a68c4725ce52a0543c7878cc
https://git.kernel.org/stable/c/d7444f91a9f93eaa48827087ed0f3381c194181d
https://git.kernel.org/stable/c/6041536d18c5f51a84bc37cd568cbab61870031e
https://git.kernel.org/stable/c/c076b3746224982eebdba5c9e4b1467e146c0d64
https://git.kernel.org/stable/c/7c244d5b48284a770d96ff703df2dfeadf804a73
https://git.kernel.org/stable/c/8ad8b531de79c348bcb8133e7f5e827b884226af
https://git.kernel.org/stable/c/2b59ffad47db1c46af25ccad157bb3b25147c35c

Timeline