iomap: fix out-of-bounds bitmap_set() with zero-length range
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 6.6.153, 6.12.101, 6.18.42, 7.1.6
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: none
- Automatable: no
- Technical impact: total
Summary
In the Linux kernel, the following vulnerability has been resolved: iomap: fix out-of-bounds bitmap_set() with zero-length range ifs_set_range_dirty() and ifs_set_range_uptodate() compute last_blk as (off + len - 1) >> i_blkbits. When off is 0 and len is 0, the unsigned subtraction underflows to SIZE_MAX, producing a huge last_blk and nr_blks value that causes bitmap_set() to write far beyond the ifs->state allocation. Regarding ifs_set_range_uptodate(), it is temporarily safe because len cannot be passed in as 0. However, for ifs_set_range_dirty() this is reachable from __iomap_write_end(): when copy_folio_from_iter_atomic() returns 0 (e.g. user buffer fault) and the folio is already uptodate, the guard at the top of __iomap_write_end() does not trigger because !folio_test_uptodate() is false, and iomap_set_range_dirty() is called with copied == 0. Add a !len guard to both functions before the computation, so that a zero-length range is a no-op.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: total
- Record last updated
Affected versions
- Linux Linux
From 4ce02c67972211be488408c275c8fbf19faf29b3 · fixed in 48829622212f6b8f49155889aecc818ba28ba680; From 4ce02c67972211be488408c275c8fbf19faf29b3 · fixed in fb4fad9105c88b1d82f1b3c39e3b6abea8249af6; From 4ce02c67972211be488408c275c8fbf19faf29b3 · fixed in 7037e7bdcd26f46c080b8ce307dee5cb471c4b7c; From 4ce02c67972211be488408c275c8fbf19faf29b3 · fixed in c5b6a48a8a716a7730e39af1cad083dc4ec955ce; From 4ce02c67972211be488408c275c8fbf19faf29b3 · fixed in 9c7d8f7c8994c790fca501dc45ce66e7356cbe05
- Linux Linux
6.6
- KernelLinux
From 6.6.0 · fixed in 6.6.153; From 6.7.0 · fixed in 6.12.101; From 6.13.0 · fixed in 6.18.42; From 6.19.0 · fixed in 7.1.6