CVE-2025-68264: Linux

EPSS: 0.2% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: ext4: refresh inline data size before write operations The cached ei->i_inline_size can become stale between the initial size check and when ext4_update_inline_data()/ext4_create_inline_data() use it. Although ext4_get_max_inline_size() reads the correct value at the time of the check, concurrent xattr operations can modify i_inline_size before ext4_write_lock_xattr() is acquired. This causes ext4_update_inline_data() and ext4_create_inline_data() to work with stale capacity values, leading to a BUG_ON() crash in ext4_write_inline_data(): kernel BUG at fs/ext4/inline.c:1331! BUG_ON(pos + len > EXT4_I(inode)->i_inline_size); The race window: 1. ext4_get_max_inline_size() reads i_inline_size = 60 (correct) 2. Size check passes for 50-byte write 3. [Another thread adds xattr, i_inline_size changes to 40] 4. ext4_write_lock_xattr() acquires lock 5. ext4_update_inline_data() uses stale i_inline_size = 60 6. Attempts to write 50 bytes but only 40 bytes actually available 7. BUG_ON() triggers Fix this by recalculating i_inline_size via ext4_find_inline_data_nolock() immediately after acquiring xattr_sem. This ensures ext4_update_inline_data() and ext4_create_inline_data() work with current values that are protected from concurrent modifications. This is similar to commit a54c4613dac1 ("ext4: fix race writing to an inline_data file while its xattrs are changing") which fixed i_inline_off staleness. This patch addresses the related i_inline_size staleness issue.

Affected products

  • Linux Linux: from 3.8, before 5.10.248 (fixed in 5.10.248); from 5.11, before 5.15.198 (fixed in 5.15.198); from 5.16, before 6.1.160 (fixed in 6.1.160); from 6.2, before 6.6.120 (fixed in 6.6.120); from 6.7, before 6.12.62 (fixed in 6.12.62); from 6.13, before 6.17.12 (fixed in 6.17.12); …
  • Siemens SIMATIC s7-1500 CPU 1518-4 Pn/dp Mfp: from V3.1.6
  • Siemens SIMATIC s7-1500 CPU 1518f-4 Pn/dp Mfp: from V3.1.6
  • Siemens Siplus s7-1500 CPU 1518-4 Pn/dp Mfp: from V3.1.6

Published 2025-12-16. Last modified 2026-07-14.