CVE-2022-50334
Unknown Unknown - Not Provided
BaseFortify

Publication date: 2025-09-15

Last updated on: 2025-12-04

Assigner: kernel.org

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 Scores
EPSS Scores
Probability:
Percentile:
Meta Information
Published
2025-09-15
Last Modified
2025-12-04
Generated
2026-05-06
AI Q&A
2025-09-15
EPSS Evaluated
2026-05-05
NVD
CVE-2022-50334
Affected Vendors & Products
Showing 5 associated CPEs
Vendor Product Version / Range
linux linux_kernel to 5.4.229 (exc)
linux linux_kernel From 5.5 (inc) to 5.10.163 (exc)
linux linux_kernel From 5.11 (inc) to 5.15.86 (exc)
linux linux_kernel From 5.16 (inc) to 6.0.16 (exc)
linux linux_kernel From 6.1 (inc) to 6.1.2 (exc)
Helpful Resources
Exploitability
CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-476 The product dereferences a pointer that it expects to be valid but is NULL.
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?

This vulnerability is a null pointer dereference in the Linux kernel's hugetlbfs_parse_param() function. When parsing mount parameters for hugetlbfs, if an illegal parameter like "size=," is given, the kernel creates a struct with a null pointer for the parameter string. The hugetlbfs_parse_param() function then dereferences this null pointer without checking, causing a null pointer dereference bug. This can lead to a kernel crash or denial of service. The issue was fixed by adding a sanity check for the null pointer before dereferencing.


How can this vulnerability impact me? :

This vulnerability can cause a kernel crash or denial of service if an attacker or user provides an illegal mount parameter to the hugetlbfs filesystem. This could disrupt system availability or stability, potentially leading to system downtime or requiring a reboot.


Ask Our AI Assistant
Need more information? Ask your question to get an AI reply (Powered by our expertise)
0/70
EPSS Chart