CVE-2022-50478

HIGH EPSS 4.7%
Published Oct 4, 20258mo ago · Modified Jun 17, 20261w ago
7.1 CVSS 3.1
High
Find Similar
Published Oct 4, 2025 8mo ago
Last Modified Jun 17, 2026 1w ago

Description

In the Linux kernel, the following vulnerability has been resolved: nilfs2: fix shift-out-of-bounds/overflow in nilfs_sb2_bad_offset() Patch series "nilfs2: fix UBSAN shift-out-of-bounds warnings on mount time". The first patch fixes a bug reported by syzbot, and the second one fixes the remaining bug of the same kind. Although they are triggered by the same super block data anomaly, I divided it into the above two because the details of the issues and how to fix it are different. Both are required to eliminate the shift-out-of-bounds issues at mount time. This patch (of 2): If the block size exponent information written in an on-disk superblock is corrupted, nilfs_sb2_bad_offset helper function can trigger shift-out-of-bounds warning followed by a kernel panic (if panic_on_warn is set): shift exponent 38983 is too large for 64-bit type 'unsigned long long' Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1b1/0x28e lib/dump_stack.c:106 ubsan_epilogue lib/ubsan.c:151 [inline] __ubsan_handle_shift_out_of_bounds+0x33d/0x3b0 lib/ubsan.c:322 nilfs_sb2_bad_offset fs/nilfs2/the_nilfs.c:449 [inline] nilfs_load_super_block+0xdf5/0xe00 fs/nilfs2/the_nilfs.c:523 init_nilfs+0xb7/0x7d0 fs/nilfs2/the_nilfs.c:577 nilfs_fill_super+0xb1/0x5d0 fs/nilfs2/super.c:1047 nilfs_mount+0x613/0x9b0 fs/nilfs2/super.c:1317 ... In addition, since nilfs_sb2_bad_offset() performs multiplication without considering the upper bound, the computation may overflow if the disk layout parameters are not normal. This fixes these issues by inserting preliminary sanity checks for those parameters and by converting the comparison from one involving multiplication and left bit-shifting to one using division and right bit-shifting.

CVSS Details

Base Score
7.1
Exploitability
1.8
Impact
5.2
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality High
Integrity None
Availability High

Threat Intelligence

EPSS Exploit Probability
4.7% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 1

CWE-125 Out-of-bounds Read Memory Safety

Affected Products 8

VendorProductVersionRange
linuxlinux_kernel*≥2.6.30  –  <4.9.337
linuxlinux_kernel*≥4.10  –  <4.14.303
linuxlinux_kernel*≥4.15  –  <4.19.270
linuxlinux_kernel*≥4.20  –  <5.4.229
linuxlinux_kernel*≥5.5  –  <5.10.163
linuxlinux_kernel*≥5.11  –  <5.15.86
linuxlinux_kernel*≥5.16  –  <6.0.16
linuxlinux_kernel*≥6.1  –  <6.1.2

References 9

  • git.kernel.org https://git.kernel.org/stable/c/1012ff77284e3bec0ec0a35a820b03ec43dec2cc
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/610a2a3d7d8be3537458a378ec69396a76c385b6
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/62d11ec205ef14d8acf172cfc9904fdbf200025a
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/6b0ea3df56cccd53398d0289f399f19d43136b2e
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/9b3ba54025357440d6c4414c670984f628c6f6bf
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/a6f89b10042baca218c8598d6db5a44c7e32625f
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/b47f5c579c8186f7f5ab5e4254e0734ea5b7bf7a
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/d464b035c0613856d012cf1704879d3ff3f057fb
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/d706485dffbbbf848e681edda29c7a46ac55698c
    Patch

Remediation

  • git.kernel.org https://git.kernel.org/stable/c/1012ff77284e3bec0ec0a35a820b03ec43dec2cc
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/610a2a3d7d8be3537458a378ec69396a76c385b6
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/62d11ec205ef14d8acf172cfc9904fdbf200025a
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/6b0ea3df56cccd53398d0289f399f19d43136b2e
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/9b3ba54025357440d6c4414c670984f628c6f6bf
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/a6f89b10042baca218c8598d6db5a44c7e32625f
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/b47f5c579c8186f7f5ab5e4254e0734ea5b7bf7a
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/d464b035c0613856d012cf1704879d3ff3f057fb
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/d706485dffbbbf848e681edda29c7a46ac55698c
    Patch