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Cc: Reported-by: syzbot+03c68e42ce4b33f7ce9b@syzkaller.appspotmail.com Tested-by: syzbot+03c68e42ce4b33f7ce9b@syzkaller.appspotmail.com Link: https://syzkaller.appspot.com/bug?extid=03c68e42ce4b33f7ce9b Signed-off-by: Adriano Cordova --- fs/ecryptfs/ecryptfs_kernel.h | 6 ++++++ fs/ecryptfs/keystore.c | 7 +++++++ 2 files changed, 13 insertions(+) diff --git a/fs/ecryptfs/ecryptfs_kernel.h b/fs/ecryptfs/ecryptfs_kernel.h index 58165928ed1e..4315c18ba1cd 100644 --- a/fs/ecryptfs/ecryptfs_kernel.h +++ b/fs/ecryptfs/ecryptfs_kernel.h @@ -88,6 +88,9 @@ ecryptfs_get_encrypted_key_payload_data(struct key *key) if (!payload) return ERR_PTR(-EKEYREVOKED); + if (payload->payload_datalen < sizeof(struct ecryptfs_auth_tok)) + return ERR_PTR(-EINVAL); + return (struct ecryptfs_auth_tok *)payload->payload_data; } @@ -124,6 +127,9 @@ ecryptfs_get_key_payload_data(struct key *key) if (!ukp) return ERR_PTR(-EKEYREVOKED); + if (ukp->datalen < sizeof(struct ecryptfs_auth_tok)) + return ERR_PTR(-EINVAL); + return (struct ecryptfs_auth_tok *)ukp->data; } diff --git a/fs/ecryptfs/keystore.c b/fs/ecryptfs/keystore.c index 51651314b7a6..7f2dbc81fcbc 100644 --- a/fs/ecryptfs/keystore.c +++ b/fs/ecryptfs/keystore.c @@ -477,6 +477,13 @@ ecryptfs_verify_auth_tok_from_key(struct key *auth_tok_key, rc = -EINVAL; goto out; } + if ((*auth_tok)->token_type == ECRYPTFS_PASSWORD + && (*auth_tok)->token.password.session_key_encryption_key_bytes + > ECRYPTFS_MAX_KEY_BYTES) { + printk(KERN_ERR "Invalid password auth_tok sKEK size\n"); + rc = -EINVAL; + goto out; + } out: return rc; } -- 2.51.0