Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: ext4: fix out-of-bounds read in ext4_read_inline_dir() ext4_read_inline_dir() can read a dirent header past the end of its inline buffer, triggering a slab-out-of-bounds read during getdents64(): BUG: KASAN: slab-out-of-bounds in __ext4_check_dir_entry Read of size 2 at addr ffff88800f3dd23c by task exploit/148 ... __ext4_check_dir_entry ext4_read_inline_dir iterate_dir The dirent payload lives in a buffer of exactly inline_size bytes: dir_buf = kmalloc(inline_size, GFP_NOFS); but iteration runs in a position space extra_offset bytes larger (extra_size = extra_offset + inline_size) so the synthetic "." and ".." land at their block-dir offsets. A dirent is formed at "dir_buf + pos - extra_offset", yet the ext4_check_dir_entry() length argument uses the larger extra_size. A position whose dirent header would extend past extra_size is therefore accepted, and the rescan loop's rec_len probe and ext4_check_dir_entry() dereference de->rec_len before the entry is rejected. Reject a position whose minimum-size dirent header would not fit within extra_size before forming de, in both the rescan and main loops, and pass inline_size rather than extra_size to ext4_check_dir_entry() so the length check matches the physical buffer.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected c4d8b0235aa98f8c26bf94d308be3fdd24154572 before d1e7c186555ad65554fd2f2b02f5a539aa35ae48; affected c4d8b0235aa98f8c26bf94d308be3fdd24154572 before 5fd20d4e50dd6e460b3ea8e4396f8553d4526f8f; affected c4d8b0235aa98f8c26bf94d308be3fdd24154572 before 1a1dea633b724a1c042dbcdb1fed27f410916688; affected c4d8b0235aa98f8c26bf94d308be3fdd24154572 before b060861f662d4826dc700a1c3584243bb3474cfe; affected c4d8b0235aa98f8c26bf94d308be3fdd24154572 before 6702c7da86d8cdb88d0fc57166286e115ffeb8c0; affected c4d8b0235aa98f8c26bf94d308be3fdd24154572 before 36bf17bb90cdf7a623499b624b05acde4d2feef5; affected c4d8b0235aa98f8c26bf94d308be3fdd24154572 before 9333cc809f0a89e001b814155a6cb8903a6274df |
| Linux / Linux | affected 3.10; unaffected 0 before 3.10; unaffected 5.15.221 through 5.15.*; unaffected 6.1.188 through 6.1.*; unaffected 6.6.157 through 6.6.*; unaffected 6.12.110 through 6.12.*; unaffected 6.18.52 through 6.18.*; unaffected 7.2.6 through 7.2.*; unaffected 7.3 through * |
CWE
No CWE identifiers supplied.
References
- https://git.kernel.org/stable/c/d1e7c186555ad65554fd2f2b02f5a539aa35ae48
- https://git.kernel.org/stable/c/5fd20d4e50dd6e460b3ea8e4396f8553d4526f8f
- https://git.kernel.org/stable/c/1a1dea633b724a1c042dbcdb1fed27f410916688
- https://git.kernel.org/stable/c/b060861f662d4826dc700a1c3584243bb3474cfe
- https://git.kernel.org/stable/c/6702c7da86d8cdb88d0fc57166286e115ffeb8c0
- https://git.kernel.org/stable/c/36bf17bb90cdf7a623499b624b05acde4d2feef5
- https://git.kernel.org/stable/c/9333cc809f0a89e001b814155a6cb8903a6274df