CVE-2025-38222
CVE-2025-38222CVE-2025-38222
linux / linux_kernel
Description
In the Linux kernel, the following vulnerability has been resolved:
ext4: inline: fix len overflow in ext4_prepare_inline_data
When running the following code on an ext4 filesystem with inline_data
feature enabled, it will lead to the bug below.
fd = open("file1", O_RDWR | O_CREAT | O_TRUNC, 0666);
ftruncate(fd, 30);
pwrite(fd, "a", 1, (1UL << 40) + 5UL);
That happens because write_begin will succeed as when
ext4_generic_write_inline_data calls ext4_prepare_inline_data, pos + len
will be truncated, leading to ext4_prepare_inline_data parameter to be 6
instead of 0x10000000006.
Then, later when write_end is called, we hit:
BUG_ON(pos + len > EXT4_I(inode)->i_inline_size);
at ext4_write_inline_data.
Fix it by using a loff_t type for the len parameter in
ext4_prepare_inline_data instead of an unsigned int.
[ 44.545164] ------------[ cut here ]------------
[ 44.545530] kernel BUG at fs/ext4/inline.c:240!
[ 44.545834] Oops: invalid opcode: 0000
Scoring
| CVSS | 5.5 () |
| Vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
| Last modified | 2026-11-05 |