Description
In the Linux kernel, the following vulnerability has been resolved: hfsplus: fix uninit-value by validating catalog record size Syzbot reported a KMSAN uninit-value issue in hfsplus_strcasecmp(). The root cause is that hfs_brec_read() doesn't validate that the on-disk record size matches the expected size for the record type being read. When mounting a corrupted filesystem, hfs_brec_read() may read less data than expected. For example, when reading a catalog thread record, the debug output showed: HFSPLUS_BREC_READ: rec_len=520, fd->entrylength=26 HFSPLUS_BREC_READ: WARNING - entrylength (26) < rec_len (520) - PARTIAL READ! hfs_brec_read() only validates that entrylength is not greater than the buffer size, but doesn't check if it's less than expected. It successfully reads 26 bytes into a 520-byte structure and returns success, leaving 494 bytes uninitialized. This uninitialized data in tmp.thread.nodeName then gets copied by hfsplus_cat_build_key_uni() and used by hfsplus_strcasecmp(), triggering the KMSAN warning when the uninitialized bytes are used as array indices in case_fold(). Fix by introducing hfsplus_brec_read_cat() wrapper that: 1. Calls hfs_brec_read() to read the data 2. Validates the record size based on the type field: - Fixed size for folder and file records - Variable size for thread records (depends on string length) 3. Returns -EIO if size doesn't match expected For thread records, check against HFSPLUS_MIN_THREAD_SZ before reading nodeName.length to avoid reading uninitialized data at call sites that don't zero-initialize the entry structure. Also initialize the tmp variable in hfsplus_find_cat() as defensive programming to ensure no uninitialized data even if validation is bypassed.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to < 3003dbf62d151d47a6b90f71655292a51a05f244affected1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to < 8be69532e399eec9d9d990f6958b4ff2383b19b3affected1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to < 3bc337697c66db2e2a4a94f0509c282c1a014b86affected1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to < 61a790974ff7e533acbceca06c7d02f22bf96d4daffected1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to < c91bbd6193c70a02c50c22e0fb1f60c3c5bd053aaffected1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to < a420904450962a562ad053a41a53a27755021b48affected1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to < 93e8d613f1a01b6637f387cc93f184cf7fb881d6affected1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to < b6b592275aeff184aa82fcf6abccd833fb71b393affected
Linux Linux
Default version status: affected
2.6.12affected0 to < 2.6.12unaffected5.10.259 to ≤ 5.10.*unaffected5.15.210 to ≤ 5.15.*unaffected6.1.176 to ≤ 6.1.*unaffected6.6.140 to ≤ 6.6.*unaffected6.12.88 to ≤ 6.12.*unaffected6.18.30 to ≤ 6.18.*unaffected7.0.7 to ≤ 7.0.*unaffected7.1 to ≤ *unaffected
References
- https://git.kernel.org/stable/c/3003dbf62d151d47a6b90f71655292a51a05f244 ↗
- https://git.kernel.org/stable/c/8be69532e399eec9d9d990f6958b4ff2383b19b3 ↗
- https://git.kernel.org/stable/c/3bc337697c66db2e2a4a94f0509c282c1a014b86 ↗
- https://git.kernel.org/stable/c/61a790974ff7e533acbceca06c7d02f22bf96d4d ↗
- https://git.kernel.org/stable/c/c91bbd6193c70a02c50c22e0fb1f60c3c5bd053a ↗
- https://git.kernel.org/stable/c/a420904450962a562ad053a41a53a27755021b48 ↗
- https://git.kernel.org/stable/c/93e8d613f1a01b6637f387cc93f184cf7fb881d6 ↗
- https://git.kernel.org/stable/c/b6b592275aeff184aa82fcf6abccd833fb71b393 ↗