CVE-2025-38701

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

ext4: do not BUG when INLINE_DATA_FL lacks system.data xattr

A syzbot fuzzed image triggered a BUG_ON in ext4_update_inline_data() when an inode had the INLINE_DATA_FL flag set but was missing the system.data extended attribute.

Since this can happen due to a maiciouly fuzzed file system, we shouldnt BUG, but rather, report it as a corrupted file system.

Add similar replacements of BUG_ON with EXT4_ERROR_INODE() ii ext4_create_inline_data() and ext4_inline_data_truncate().

Weakness

The product contains an assert() or similar statement that can be triggered by an attacker, which leads to an application exit or other behavior that is more severe than necessary.

Affected Software

Extended Description

While assertion is good for catching logic errors and reducing the chances of reaching more serious vulnerability conditions, it can still lead to a denial of service. For example, if a server handles multiple simultaneous connections, and an assert() occurs in one single connection that causes all other connections to be dropped, this is a reachable assertion that leads to a denial of service.

Potential Mitigations

References

• https://git.kernel.org/stable/c/099b847ccc6c1ad2f805d13cfbcc83f5b6d4bc42
• https://git.kernel.org/stable/c/1199a6399895f4767f0b9a68a6ff47c3f799b7c7
• https://git.kernel.org/stable/c/279c87ef7b9da34f65c2e4db586e730b667a6fb9
• https://git.kernel.org/stable/c/2817ac83cb4732597bf36853fe13ca616f4ee4e2
• https://git.kernel.org/stable/c/7f322c12df7aeed1755acd3c6fab48c7807795fb
• https://git.kernel.org/stable/c/8085a7324d8ec448c4a764af7853e19bbd64e17a
• https://git.kernel.org/stable/c/81e7e2e7ba07e7c8cdce43ccad2f91adbc5a919c
• https://git.kernel.org/stable/c/8a6f89d42e61788605722dd9faf98797c958a7e5
• https://git.kernel.org/stable/c/d960f4b793912f35e9d72bd9d1e90553063fcbf1
• https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html
• https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html