diff options
| author | Shyam Prasad N <sprasad@microsoft.com> | 2023-03-20 06:08:19 +0000 |
|---|---|---|
| committer | Steve French <stfrench@microsoft.com> | 2023-03-24 09:03:55 -0500 |
| commit | bc962159e8e326af634a506508034a375bf2b858 (patch) | |
| tree | 733ddaf358a6b9473122feca390378103bac5f58 /fs/cifs/smb2transport.c | |
| parent | fddc6ccc487e5de07b98df8d04118d5dcb5e0407 (diff) | |
cifs: avoid race conditions with parallel reconnects
When multiple processes/channels do reconnects in parallel
we used to return success immediately
negotiate/session-setup/tree-connect, causing race conditions
between processes that enter the function in parallel.
This caused several errors related to session not found to
show up during parallel reconnects.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
Diffstat (limited to 'fs/cifs/smb2transport.c')
| -rw-r--r-- | fs/cifs/smb2transport.c | 17 |
1 files changed, 14 insertions, 3 deletions
diff --git a/fs/cifs/smb2transport.c b/fs/cifs/smb2transport.c index d827b7547ffa..790acf65a092 100644 --- a/fs/cifs/smb2transport.c +++ b/fs/cifs/smb2transport.c @@ -81,6 +81,7 @@ int smb2_get_sign_key(__u64 ses_id, struct TCP_Server_Info *server, u8 *key) struct cifs_ses *ses = NULL; int i; int rc = 0; + bool is_binding = false; spin_lock(&cifs_tcp_ses_lock); @@ -97,9 +98,12 @@ int smb2_get_sign_key(__u64 ses_id, struct TCP_Server_Info *server, u8 *key) goto out; found: + spin_lock(&ses->ses_lock); spin_lock(&ses->chan_lock); - if (cifs_chan_needs_reconnect(ses, server) && - !CIFS_ALL_CHANS_NEED_RECONNECT(ses)) { + + is_binding = (cifs_chan_needs_reconnect(ses, server) && + ses->ses_status == SES_GOOD); + if (is_binding) { /* * If we are in the process of binding a new channel * to an existing session, use the master connection @@ -107,6 +111,7 @@ found: */ memcpy(key, ses->smb3signingkey, SMB3_SIGN_KEY_SIZE); spin_unlock(&ses->chan_lock); + spin_unlock(&ses->ses_lock); goto out; } @@ -119,10 +124,12 @@ found: if (chan->server == server) { memcpy(key, chan->signkey, SMB3_SIGN_KEY_SIZE); spin_unlock(&ses->chan_lock); + spin_unlock(&ses->ses_lock); goto out; } } spin_unlock(&ses->chan_lock); + spin_unlock(&ses->ses_lock); cifs_dbg(VFS, "%s: Could not find channel signing key for session 0x%llx\n", @@ -392,11 +399,15 @@ generate_smb3signingkey(struct cifs_ses *ses, bool is_binding = false; int chan_index = 0; + spin_lock(&ses->ses_lock); spin_lock(&ses->chan_lock); - is_binding = !CIFS_ALL_CHANS_NEED_RECONNECT(ses); + is_binding = (cifs_chan_needs_reconnect(ses, server) && + ses->ses_status == SES_GOOD); + chan_index = cifs_ses_get_chan_index(ses, server); /* TODO: introduce ref counting for channels when the can be freed */ spin_unlock(&ses->chan_lock); + spin_unlock(&ses->ses_lock); /* * All channels use the same encryption/decryption keys but |