s390/dasd: Fix undersized format-check buffer
- 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- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean?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 6.6.151, 6.12.103, 6.18.44, 7.1.8
- 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: s390/dasd: Fix undersized format-check buffer fmt_buffer_size in dasd_eckd_check_device_format() is declared as int, even though one of the multiplicands, sizeof(struct eckd_count), is a size_t. The expression trkcount * rpt_max * sizeof(struct eckd_count) is therefore correctly evaluated at 64-bit width, but the result is silently truncated when it is stored back into the 32-bit fmt_buffer_size variable. For a sufficiently large track range (start_unit/stop_unit are caller-controlled) this truncation yields a buffer size far smaller than the number of tracks actually requested. kzalloc() then succeeds with an undersized allocation, while the subsequent channel program build still operates on the untruncated track count and writes past the end of that buffer. Compute the buffer size with check_mul_overflow() and keep it in a size_t, so that a value that no longer fits results in -EINVAL instead of a silently truncated allocation size.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: total
- Record last updated
Affected versions
- Linux Linux
From 8fd575200db5b53f6ea6818dd017f1b43190db12 · fixed in aca18289c86f22d3fc2f3f6ff615286e7b1702f6; From 8fd575200db5b53f6ea6818dd017f1b43190db12 · fixed in 9f88dda2f22927d22498801a92cab6a9424eaf86; From 8fd575200db5b53f6ea6818dd017f1b43190db12 · fixed in e16e0fc54120cee3c6f0362de95aab6792865857; From 8fd575200db5b53f6ea6818dd017f1b43190db12 · fixed in 87f3389cd3920714c53e704778f7ca7f1cf0c39c; From 8fd575200db5b53f6ea6818dd017f1b43190db12 · fixed in 7f40b346462f563a0d6e841a77b5163d2a882a04
- Linux Linux
4.7
- KernelLinux
From 4.7.0 · fixed in 6.6.151; From 6.7.0 · fixed in 6.12.103; From 6.13.0 · fixed in 6.18.44; From 6.19.0 · fixed in 7.1.8