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Diffstat (limited to 'drivers/md/dm-pcache/cache.h')
| -rw-r--r-- | drivers/md/dm-pcache/cache.h | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/drivers/md/dm-pcache/cache.h b/drivers/md/dm-pcache/cache.h index 27613b56be54..afc112b79496 100644 --- a/drivers/md/dm-pcache/cache.h +++ b/drivers/md/dm-pcache/cache.h @@ -491,6 +491,27 @@ static inline u32 cache_key_data_crc(struct pcache_cache_key *key) return crc32c(PCACHE_CRC_SEED, data, key->len); } +/** + * kset_onmedia_valid - Validate a kset header read from the cache device. + * @kset_onmedia: Pointer to the kset copied from on-media metadata. + * + * The magic and CRC are attacker-computable (fixed public seed). A non-last + * kset stores key_num keys inline, and cache_kset_crc() and the replay loop + * read struct_size(.., data, key_num) bytes from a buffer sized for + * PCACHE_KSET_KEYS_MAX keys, so key_num must be bounded before any such use. + */ +static inline bool kset_onmedia_valid(struct pcache_cache_kset_onmedia *kset_onmedia) +{ + if (kset_onmedia->magic != PCACHE_KSET_MAGIC) + return false; + + if (!(kset_onmedia->flags & PCACHE_KSET_FLAGS_LAST) && + kset_onmedia->key_num > PCACHE_KSET_KEYS_MAX) + return false; + + return true; +} + static inline u32 cache_kset_crc(struct pcache_cache_kset_onmedia *kset_onmedia) { u32 crc_size; |