kernel/linux.git/fs/smb/client/dfs_cache.c, branch v6.18.22Linux kernel stable tree (mirror)https://git.radix-linux.su/kernel/linux.git/atom?h=v6.18.222025-10-30T01:13:05+00:00smb: client: handle lack of IPC in dfs_cache_refresh()2025-10-30T01:13:05+00:00Paulo Alcantarapc@manguebit.org2025-10-23T21:59:47+00:00urn:sha1:fac56c4651ae95f3f2b468c2cf1884cf0e6d18c1
In very rare cases, DFS mounts could end up with SMB sessions without
any IPC connections. These mounts are only possible when having
unexpired cached DFS referrals, hence not requiring any IPC
connections during the mount process.
Try to establish those missing IPC connections when refreshing DFS
referrals. If the server is still rejecting it, then simply ignore
and leave expired cached DFS referral for any potential DFS failovers.
Reported-by: Jay Shin <jaeshin@redhat.com>
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.org>
Cc: David Howells <dhowells@redhat.com>
Cc: linux-cifs@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
smb: client: get rid of kstrdup() in get_ses_refpath()2025-02-06T03:09:07+00:00Paulo Alcantarapc@manguebit.com2025-02-05T16:41:32+00:00urn:sha1:be1963dd4ce4e467f062b023d1e696f40c926a04
After commit 36008fe6e3dc ("smb: client: don't try following DFS links
in cifs_tree_connect()"), TCP_Server_Info::leaf_fullpath will no
longer be changed, so there is no need to kstrdup() it.
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
smb: client: get rid of TCP_Server_Info::refpath_lock2025-01-23T02:13:49+00:00Paulo Alcantarapc@manguebit.com2025-01-17T20:38:56+00:00urn:sha1:0a9b00e5e5c5fc3c77cbfd01e6ffbe77fc7fe74a
TCP_Server_Info::leaf_fullpath is allocated in cifs_get_tcp_session()
and never changed afterwards, so there is no need to serialize its
access.
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
smb: client: provide dns_resolve_{unc,name} helpers2025-01-20T01:34:00+00:00Paulo Alcantarapc@manguebit.com2025-01-07T15:22:50+00:00urn:sha1:4b1b4c8be9dee9aa1a751cfa3954b2fcfdfe9c3d
Some places pass hostnames rather than UNC paths to resolve them to ip
addresses, so provide helpers to handle both cases and then stop
converting hostnames to UNC paths by inserting path delimiters into
them. Also kill @expiry parameter as it's not used anywhere.
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
smb: client: fix DFS mount against old servers with NTLMSSP2025-01-20T01:34:00+00:00Paulo Alcantarapc@manguebit.com2025-01-03T19:58:12+00:00urn:sha1:ad46faff1afcc8db72f9954a6ea2296d31259217
Old Windows servers will return not fully qualified DFS targets by
default as specified in
MS-DFSC 3.2.5.5 Receiving a Root Referral Request or Link Referral
Request
| Servers SHOULD<30> return fully qualified DNS host names of
| targets in responses to root referral requests and link referral
| requests.
| ...
| <30> Section 3.2.5.5: By default, Windows Server 2003, Windows
| Server 2008, Windows Server 2008 R2, Windows Server 2012, and
| Windows Server 2012 R2 return DNS host names that are not fully
| qualified for targets.
Fix this by converting all NetBIOS host names from DFS targets to
FQDNs and try resolving them first if DNS domain name was provided in
NTLMSSP CHALLENGE_MESSAGE message from previous SMB2_SESSION_SETUP.
This also prevents the client from translating the DFS target
hostnames to another domain depending on the network domain search
order.
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
smb: client: allow more DFS referrals to be cached2024-11-27T00:46:15+00:00Paulo Alcantarapc@manguebit.com2024-11-26T20:19:18+00:00urn:sha1:28ec614f2f9bfb57a76dd387be67bb6054f96b04
In some DFS setups, a single DFS share may contain hundreds of DFS
links and increasing the DFS cache to allow more referrals to be
cached improves DFS failover as the client will likely find a cached
DFS referral when reconnecting and then avoiding unnecessary remounts.
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
smb: client: Use str_yes_no() helper function2024-11-18T04:20:54+00:00Thorsten Blumthorsten.blum@linux.dev2024-11-12T10:58:38+00:00urn:sha1:7460bf441656cebc2636189ab9ba9a65a0a8ab86
Remove hard-coded strings by using the str_yes_no() helper function.
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: Steve French <stfrench@microsoft.com>
smb: client: fix DFS interlink failover2024-09-25T02:51:48+00:00Paulo Alcantarapc@manguebit.com2024-09-18T05:03:55+00:00urn:sha1:4f42a8b54b5c6e36519aef3cb1f6210e54abd451
The DFS interlinks point to different DFS namespaces so make sure to
use the correct DFS root server to chase any DFS links under it by
storing the SMB session in dfs_ref_walk structure and then using it on
every referral walk.
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
smb: client: improve purging of cached referrals2024-09-25T02:51:48+00:00Paulo Alcantarapc@manguebit.com2024-09-18T05:03:45+00:00urn:sha1:9190cc0c97aafdae06015d468c6ca3991e32a23a
Purge cached referrals that have a single target when reaching maximum
of cache size as the client won't need them to failover. Otherwise
remove oldest cache entry.
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
smb: client: avoid unnecessary reconnects when refreshing referrals2024-09-25T02:51:47+00:00Paulo Alcantarapc@manguebit.com2024-09-18T05:03:35+00:00urn:sha1:242d23efc987151ecd34bc0cae4c0b737494fc40
Do not mark tcons for reconnect when current connection matches any of
the targets returned by new referral even when there is no cached
entry.
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>