CVE-2022-50334

Advisory lineage Upstream: 0 Downstream: 8
Analyzed
Published: 15 Sept 2025, 14:49
Last modified:11 May 2026, 19:17

Vulnerability Summary

Overall Risk (default)
low
22/100
CVSS Score
5.5 MEDIUM
v3.1 (nvd)
EPSS Score
0.02% LOW
0% probability 0.00%
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

15 Sept 2025, 14:49
Published
Vulnerability first disclosed
11 May 2026, 19:17
Last Modified
Vulnerability information updated

Description

In the Linux kernel, the following vulnerability has been resolved: hugetlbfs: fix null-ptr-deref in hugetlbfs_parse_param() Syzkaller reports a null-ptr-deref bug as follows: ====================================================== KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] RIP: 0010:hugetlbfs_parse_param+0x1dd/0x8e0 fs/hugetlbfs/inode.c:1380 [...] Call Trace: <TASK> vfs_parse_fs_param fs/fs_context.c:148 [inline] vfs_parse_fs_param+0x1f9/0x3c0 fs/fs_context.c:129 vfs_parse_fs_string+0xdb/0x170 fs/fs_context.c:191 generic_parse_monolithic+0x16f/0x1f0 fs/fs_context.c:231 do_new_mount fs/namespace.c:3036 [inline] path_mount+0x12de/0x1e20 fs/namespace.c:3370 do_mount fs/namespace.c:3383 [inline] __do_sys_mount fs/namespace.c:3591 [inline] __se_sys_mount fs/namespace.c:3568 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3568 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd [...] </TASK> ====================================================== According to commit "vfs: parse: deal with zero length string value", kernel will set the param->string to null pointer in vfs_parse_fs_string() if fs string has zero length. Yet the problem is that, hugetlbfs_parse_param() will dereference the param->string, without checking whether it is a null pointer. To be more specific, if hugetlbfs_parse_param() parses an illegal mount parameter, such as "size=,", kernel will constructs struct fs_parameter with null pointer in vfs_parse_fs_string(), then passes this struct fs_parameter to hugetlbfs_parse_param(), which triggers the above null-ptr-deref bug. This patch solves it by adding sanity check on param->string in hugetlbfs_parse_param().

CVSS Metrics

  • v3.1•MEDIUM•Score: 5.5CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS Trends

Current EPSS score: 0.02%• Percentile: 4%

Techniques & Countermeasures

  • CWE-476•NULL Pointer Dereference

    The product dereferences a pointer that it expects to be valid but is NULL.

Affected Systems

  • linux•linux

    ≥ 32021982a324dce93b4ae00c06213bf45fb319c8, < fa71639873518e3587632ae58e25e4a96b57fa90 | ≥ 32021982a324dce93b4ae00c06213bf45fb319c8, < dcd28191be9bbf307ba51a5b485773a55b0037c4 | ≥ 32021982a324dce93b4ae00c06213bf45fb319c8, < 9a8862820cbf1f18dca4f3b4c289d88561b3a384 | ≥ 32021982a324dce93b4ae00c06213bf45fb319c8, < 965e8f8ae0f642b5528f5a82b7bcaf15a659d5bd | ≥ 32021982a324dce93b4ae00c06213bf45fb319c8, < f2207145693ae5697a7b59e2add4b92f9e5b0e3c | ≥ 32021982a324dce93b4ae00c06213bf45fb319c8, < 26215b7ee923b9251f7bb12c4e5f09dc465d35f2 | 5.1

  • linux•linux_kernel

    < 5.4.229 | ≥ 5.5, < 5.10.163 | ≥ 5.11, < 5.15.86 | ≥ 5.16, < 6.0.16 | ≥ 6.1, < 6.1.2

References (6)