cifs: return correct error in ->calc_signature()

[ Upstream commit 09a1f9a168ae1f69f701689429871793174417d2 ]

If an error happens while getting the key or session in the
->calc_signature implementations, 0 (success) is returned. Fix it by
returning a proper error code.

Since it seems to be highly unlikely to happen wrap the rc check in
unlikely() too.

Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Fixes: 32811d242ff6 ("cifs: Start using per session key for smb2/3 for signature generation")
Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/cifs/smb2transport.c b/fs/cifs/smb2transport.c
index f59b956f9d2502cdaea6bcb9e89319d24c4d4100..390cc5e8c74670a57d79072903893a3901f408a3 100644 (file)
--- a/fs/cifs/smb2transport.c
+++ b/fs/cifs/smb2transport.c
@@ -221,9 +221,9 @@ smb2_calc_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server,
        struct smb_rqst drqst;
 
        ses = smb2_find_smb_ses(server, shdr->SessionId);
-       if (!ses) {
+       if (unlikely(!ses)) {
                cifs_server_dbg(VFS, "%s: Could not find session\n", __func__);
-               return 0;
+               return -ENOENT;
        }
 
        memset(smb2_signature, 0x0, SMB2_HMACSHA256_SIZE);
@@ -542,8 +542,10 @@ smb3_calc_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server,
        u8 key[SMB3_SIGN_KEY_SIZE];
 
        rc = smb2_get_sign_key(shdr->SessionId, server, key);
-       if (rc)
-               return 0;
+       if (unlikely(rc)) {
+               cifs_server_dbg(VFS, "%s: Could not get signing key\n", __func__);
+               return rc;
+       }
 
        if (allocate_crypto) {
                rc = cifs_alloc_hash("cmac(aes)", &hash, &sdesc);