Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: lockd: Avoid hashing uninitialized bytes in nlm4svc_lookup_file() file_hash() digests the first LOCKD_FH_HASH_SIZE bytes of nfs_fh.data when bucketing nlm_files[], independent of fh.size. Commit 3de744ee4e45 ("lockd: Use xdrgen XDR functions for the NLMv4 TEST procedure") set .pc_argzero to zero for the converted procedures and moved file-handle population into nlm4svc_lookup_file(), which copies only xdr_lock->fh.len bytes into lock->fh.data. When an NLMv4 client presents a file handle shorter than LOCKD_FH_HASH_SIZE, bytes fh.len..31 retain whatever the argument buffer held from an earlier request. The same wire handle then hashes to different buckets across calls; nlm_lookup_file() misses the existing nlm_file entry, and lock-state lookups fail. Zero only the tail bytes that file_hash() would otherwise consume. Handles of LOCKD_FH_HASH_SIZE or larger already populate every byte that file_hash() reads.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected 3de744ee4e4557da0d63be8a97ad44b4dad58912 before 686c2434f9f16b87aeed18d76cc562df9f2695ab; affected 3de744ee4e4557da0d63be8a97ad44b4dad58912 before 6e4c62caecf792e8a15ad9bc7f371e57c17e3302 |
| Linux / Linux | affected 7.1; unaffected 0 before 7.1; unaffected 7.1.5 through 7.1.*; unaffected 7.2 through * |
CWE
No CWE identifiers supplied.