Unauthenticated Remote Vulnerability in Linux Linux Kernel Rates 9.8 CVSS

Status: UPDATED  |  Advisory ID: CVE-2026-74350

Key Details

Affected Products, Subsystems & Sectors

What to Know

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

ocfs2: validate fast symlink target during inode read

ocfs2_validate_inode_block() already rejects several inconsistent

self-contained dinodes before they are exposed to the rest of the

filesystem. Fast symlinks need the same treatment.

A zero-cluster symlink is treated as a fast symlink and later read through

page_get_link() and ocfs2_fast_symlink_read_folio(). That path uses

strnlen() on the inline payload and then copies len + 1 bytes into the

folio. If a corrupt dinode stores an i_size that does not fit the inline

area or omits the terminating NUL at i_size, that copy reads past the end

of the inode block buffer.

Reject zero-cluster symlink dinodes whose i_size exceeds the inline

fast-symlink capacity or whose inline payload is not NUL-terminated

exactly at i_size when the inode block is validated. This keeps malformed

fast symlinks from reaching the read path.

Validation reproduced this kernel report:

KASAN use-after-free in ocfs2_fast_symlink_read_folio+0x12c/0x1f0

RIP: 0033:0x7f5c6d859aa7

Read of size 3905

Call trace:

dump_stack_lvl+0x66/0xa0 (?:?)

print_report+0xce/0x630 (?:?)

ocfs2_fast_symlink_read_folio+0x12c/0x1f0 (fs/ocfs2/inode.c:?)

srso_alias_return_thunk+0x5/0xfbef5 (?:?)

__virt_addr_valid+0x19f/0x330 (?:?)

kasan_report+0xe0/0x110 (?:?)

kasan_check_range+0x105/0x1b0 (?:?)

__asan_memcpy+0x23/0x60 (?:?)

filemap_read_folio+0x27/0xe0 (?:?)

filemap_read_folio+0x35/0xe0 (?:?)

do_read_cache_folio+0x138/0x230 (?:?)

__page_get_link+0x26/0x110 (?:?)

page_get_link+0x2e/0x70 (?:?)

vfs_readlink+0x15e/0x250 (?:?)

touch_atime+0x4d/0x370 (?:?)

do_readlinkat+0x186/0x200 (?:?)

do_user_addr_fault+0x65a/0x890 (?:?)

__x64_sys_readlink+0x46/0x60 (?:?)

do_syscall_64+0x115/0x6a0 (arch/x86/entry/syscall_64.c:87)

entry_SYSCALL_64_after_hwframe+0x77/0x7f (?:?) (NVD)

What to Do

Monitor Linux's web page for any future patch releases.

References