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path: root/fs/cifs/connect.c
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2022-04-04cifs: force new session setup and tcon for dfsPaulo Alcantara
Do not reuse existing sessions and tcons in DFS failover as it might connect to different servers and shares. Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Cc: stable@vger.kernel.org Reviewed-by: Enzo Matsumiya <ematsumiya@suse.de> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-04-04cifs: fix potential race with cifsd threadPaulo Alcantara
To avoid racing with demultiplex thread while it is handling data on socket, use cifs_signal_cifsd_for_reconnect() helper for marking current server to reconnect and let the demultiplex thread handle the rest. Fixes: dca65818c80c ("cifs: use a different reconnect helper for non-cifsd threads") Reviewed-by: Enzo Matsumiya <ematsumiya@suse.de> Reviewed-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-03-28smb3: cleanup and clarify status of tree connectionsSteve French
Currently the way the tid (tree connection) status is tracked is confusing. The same enum is used for structs cifs_tcon and cifs_ses and TCP_Server_info, but each of these three has different states that they transition among. The current code also unnecessarily uses camelCase. Convert from use of statusEnum to a new tid_status_enum for tree connections. The valid states for a tid are: TID_NEW = 0, TID_GOOD, TID_EXITING, TID_NEED_RECON, TID_NEED_TCON, TID_IN_TCON, TID_NEED_FILES_INVALIDATE, /* unused, considering removing in future */ TID_IN_FILES_INVALIDATE It also removes CifsNeedTcon, CifsInTcon, CifsNeedFilesInvalidate and CifsInFilesInvalidate from the statusEnum used for session and TCP_Server_Info since they are not relevant for those. A follow on patch will fix the places where we use the tcon->need_reconnect flag to be more consistent with the tid->status. Also fixes a bug that was: Reported-by: kernel test robot <lkp@intel.com> Reviewed-by: Shyam Prasad N <sprasad@microsoft.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-03-21cifs: do not skip link targets when an I/O failsPaulo Alcantara
When I/O fails in one of the currently connected DFS targets, retry it from other targets as specified in MS-DFSC "3.1.5.2 I/O Operation to +Target Fails with an Error Other Than STATUS_PATH_NOT_COVERED." Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Cc: stable@vger.kernel.org Signed-off-by: Steve French <stfrench@microsoft.com>
2022-03-18cifs: use a different reconnect helper for non-cifsd threadsShyam Prasad N
The cifs_demultiplexer_thread should only call cifs_reconnect. If any other thread wants to trigger a reconnect, they can do so by updating the server tcpStatus to CifsNeedReconnect. The last patch attempted to use the same helper function for both types of threads, but that causes other issues with lock dependencies. This patch creates a new helper for non-cifsd threads, that will indicate to cifsd that the server needs reconnect. Fixes: 2a05137a0575 ("cifs: mark sessions for reconnection in helper function") Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-03-16smb3: fix incorrect session setup check for multiuser mountsSteve French
A recent change to how the SMB3 server (socket) and session status is managed regressed multiuser mounts by changing the check for whether session setup is needed to the socket (TCP_Server_info) structure instead of the session struct (cifs_ses). Add additional check in cifs_setup_sesion to fix this. Fixes: 73f9bfbe3d81 ("cifs: maintain a state machine for tcp/smb/tcon sessions") Reported-by: Ronnie Sahlberg <lsahlber@redhat.com> Acked-by: Ronnie Sahlberg <lsahlber@redhat.com> Reviewed-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-02-08cifs: mark sessions for reconnection in helper functionShyam Prasad N
Today we have the code to mark connections and sessions (and tcons) for reconnect clubbed with the code to close the socket and abort all mids in the same function. Sometimes, we need to mark connections and sessions outside cifsd thread. So as a part of this change, I'm splitting this function into two different functions and calling them one after the other in cifs_reconnect. Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-02-08cifs: call cifs_reconnect when a connection is markedShyam Prasad N
In cifsd thread, we should continue to call cifs_reconnect whenever server->tcpStatus is marked as CifsNeedReconnect. This was inexplicably removed by one of my recent commits. Fixing that here. Fixes: a05885ce13bd ("cifs: fix the connection state transitions with multichannel") Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-02-06[smb3] improve error message when mount options conflict with posixSteve French
POSIX extensions require SMB3.1.1 (so improve the error message when vers=3.0, 2.1 or 2.0 is specified on mount) Signed-off-by: Steve French <stfrench@microsoft.com>
2022-02-03cifs: fix workstation_name for multiuser mountsRyan Bair
Set workstation_name from the master_tcon for multiuser mounts. Just in case, protect size_of_ntlmssp_blob against a NULL workstation_name. Fixes: 49bd49f983b5 ("cifs: send workstation name during ntlmssp session setup") Cc: stable@vger.kernel.org # 5.16 Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Signed-off-by: Ryan Bair <ryandbair@gmail.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-29cifs: unlock chan_lock before calling cifs_put_tcp_sessionShyam Prasad N
While removing an smb session, we need to free up the tcp session for each channel for that session. We were doing this with chan_lock held. This results in a cyclic dependency with cifs_tcp_ses_lock. For now, unlock the chan_lock temporarily before calling cifs_put_tcp_session. This should not cause any problem for now, since we do not remove channels anywhere else. And this code segment will not be called by two threads. When we do implement the code for removing channels, we will need to execute proper ref counting here. Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-28Fix a warning about a malformed kernel doc comment in cifsDavid Howells
Fix by removing the extra asterisk. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Rohith Surabattula <rohiths@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-19cifs: Support fscache indexing rewriteDavid Howells
Change the cifs filesystem to take account of the changes to fscache's indexing rewrite and reenable caching in cifs. The following changes have been made: (1) The fscache_netfs struct is no more, and there's no need to register the filesystem as a whole. (2) The session cookie is now an fscache_volume cookie, allocated with fscache_acquire_volume(). That takes three parameters: a string representing the "volume" in the index, a string naming the cache to use (or NULL) and a u64 that conveys coherency metadata for the volume. For cifs, I've made it render the volume name string as: "cifs,<ipaddress>,<sharename>" where the sharename has '/' characters replaced with ';'. This probably needs rethinking a bit as the total name could exceed the maximum filename component length. Further, the coherency data is currently just set to 0. It needs something else doing with it - I wonder if it would suffice simply to sum the resource_id, vol_create_time and vol_serial_number or maybe hash them. (3) The fscache_cookie_def is no more and needed information is passed directly to fscache_acquire_cookie(). The cache no longer calls back into the filesystem, but rather metadata changes are indicated at other times. fscache_acquire_cookie() is passed the same keying and coherency information as before. (4) The functions to set/reset cookies are removed and fscache_use_cookie() and fscache_unuse_cookie() are used instead. fscache_use_cookie() is passed a flag to indicate if the cookie is opened for writing. fscache_unuse_cookie() is passed updates for the metadata if we changed it (ie. if the file was opened for writing). These are called when the file is opened or closed. (5) cifs_setattr_*() are made to call fscache_resize() to change the size of the cache object. (6) The functions to read and write data are stubbed out pending a conversion to use netfslib. Changes ======= ver #8: - Abstract cache invalidation into a helper function. - Fix some checkpatch warnings[3]. ver #7: - Removed the accidentally added-back call to get the super cookie in cifs_root_iget(). - Fixed the right call to cifs_fscache_get_super_cookie() to take account of the "-o fsc" mount flag. ver #6: - Moved the change of gfpflags_allow_blocking() to current_is_kswapd() for cifs here. - Fixed one of the error paths in cifs_atomic_open() to jump around the call to use the cookie. - Fixed an additional successful return in the middle of cifs_open() to use the cookie on the way out. - Only get a volume cookie (and thus inode cookies) when "-o fsc" is supplied to mount. ver #5: - Fixed a couple of bits of cookie handling[2]: - The cookie should be released in cifs_evict_inode(), not cifsFileInfo_put_final(). The cookie needs to persist beyond file closure so that writepages will be able to write to it. - fscache_use_cookie() needs to be called in cifs_atomic_open() as it is for cifs_open(). ver #4: - Fixed the use of sizeof with memset. - tcon->vol_create_time is __le64 so doesn't need cpu_to_le64(). ver #3: - Canonicalise the cifs coherency data to make the cache portable. - Set volume coherency data. ver #2: - Use gfpflags_allow_blocking() rather than using flag directly. - Upgraded to -rc4 to allow for upstream changes[1]. - fscache_acquire_volume() now returns errors. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Jeff Layton <jlayton@kernel.org> cc: Steve French <smfrench@gmail.com> cc: Shyam Prasad N <nspmangalore@gmail.com> cc: linux-cifs@vger.kernel.org cc: linux-cachefs@redhat.com Link: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=23b55d673d7527b093cd97b7c217c82e70cd1af0 [1] Link: https://lore.kernel.org/r/3419813.1641592362@warthog.procyon.org.uk/ [2] Link: https://lore.kernel.org/r/CAH2r5muTanw9pJqzAHd01d9A8keeChkzGsCEH6=0rHutVLAF-A@mail.gmail.com/ [3] Link: https://lore.kernel.org/r/163819671009.215744.11230627184193298714.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/163906982979.143852.10672081929614953210.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/163967187187.1823006.247415138444991444.stgit@warthog.procyon.org.uk/ # v3 Link: https://lore.kernel.org/r/164021579335.640689.2681324337038770579.stgit@warthog.procyon.org.uk/ # v4 Link: https://lore.kernel.org/r/3462849.1641593783@warthog.procyon.org.uk/ # v5 Link: https://lore.kernel.org/r/1318953.1642024578@warthog.procyon.org.uk/ # v6 Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-19cifs: cifs_ses_mark_for_reconnect should also update reconnect bitsShyam Prasad N
Recent restructuring of cifs_reconnect introduced a helper func named cifs_ses_mark_for_reconnect, which updates the state of tcp session for all the channels of a session for reconnect. However, this does not update the session state and chans_need_reconnect bitmask. This change fixes that. Also, cifs_mark_tcp_sess_for_reconnect should mark set the bitmask for all channels when the whole session is marked for reconnect. Fixed that here too. Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-19cifs: update tcpStatus during negotiate and sess setupShyam Prasad N
Till the end of SMB session setup, update tcpStatus and avoid updating session status field. There was a typo in cifs_setup_session, which caused ses->status to be updated instead. This was causing issues during reconnect. Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-19cifs: make status checks in version independent callersShyam Prasad N
The status of tcp session, smb session and tcon have the same flow, irrespective of the SMB version used. Hence these status checks and updates should happen in the version independent callers of these commands. Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-19cifs: remove repeated state change in dfs tree connectShyam Prasad N
cifs_tree_connect checks and sets the tidStatus for the tcon. cifs_tree_connect also calls a dfs specific tree connect function, which also does similar checks. This should not happen. Removing it with this change. Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-19cifs: fix the cifs_reconnect path for DFSShyam Prasad N
Recently, the cifs_reconnect code was refactored into two branches for regular vs dfs codepath. Some of my recent changes were missing in the dfs path, namely the code to enable periodic DNS query, and a missing lock. Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-19cifs: protect all accesses to chan_* with chan_lockShyam Prasad N
A spin lock called chan_lock was introduced recently. But not all accesses were protected. Doing that with this change. To make sure that a channel is not freed when in use, we need to introduce a ref count. But today, we don't ever free channels. Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-19cifs: fix the connection state transitions with multichannelShyam Prasad N
Recent changes to multichannel required some adjustments in the way connection states transitioned during/after reconnect. Also some minor fixes: 1. A pending switch of GlobalMid_Lock to cifs_tcp_ses_lock 2. Relocations of the code that logs reconnect 3. Changed some code in allocate_mid to suit the new scheme Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-19cifs: check reconnects for channels of active tcons tooShyam Prasad N
With the new multichannel logic, when a channel needs reconnection, the tree connect and other channels can still be active. This fix will handle cases of checking for channel reconnect, when the tcon does not need reconnect. Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-17cifs: quirk for STATUS_OBJECT_NAME_INVALID returned for non-ASCII dfs refsEugene Korenevsky
Windows SMB server responds with STATUS_OBJECT_NAME_INVALID code to SMB2 QUERY_INFO request for "\<server>\<dfsname>\<linkpath>" DFS reference, where <dfsname> contains non-ASCII unicode symbols. Check such DFS reference and emulate -EREMOTE if it is actual. BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=215440 Signed-off-by: Eugene Korenevsky <ekorenevsky@astralinux.ru> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-17Merge tag '5.17-rc-part1-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6Linus Torvalds
Pull cifs updates from Steve French: - multichannel patches mostly related to improving reconnect behavior - minor cleanup patches * tag '5.17-rc-part1-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6: cifs: fix FILE_BOTH_DIRECTORY_INFO definition cifs: move superblock magic defitions to magic.h cifs: Fix smb311_update_preauth_hash() kernel-doc comment cifs: avoid race during socket reconnect between send and recv cifs: maintain a state machine for tcp/smb/tcon sessions cifs: fix hang on cifs_get_next_mid() cifs: take cifs_tcp_ses_lock for status checks cifs: reconnect only the connection and not smb session where possible cifs: add WARN_ON for when chan_count goes below minimum cifs: adjust DebugData to use chans_need_reconnect for conn status cifs: use the chans_need_reconnect bitmap for reconnect status cifs: track individual channel status using chans_need_reconnect cifs: remove redundant assignment to pointer p
2022-01-17Merge branch 'signal-for-v5.17' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull signal/exit/ptrace updates from Eric Biederman: "This set of changes deletes some dead code, makes a lot of cleanups which hopefully make the code easier to follow, and fixes bugs found along the way. The end-game which I have not yet reached yet is for fatal signals that generate coredumps to be short-circuit deliverable from complete_signal, for force_siginfo_to_task not to require changing userspace configured signal delivery state, and for the ptrace stops to always happen in locations where we can guarantee on all architectures that the all of the registers are saved and available on the stack. Removal of profile_task_ext, profile_munmap, and profile_handoff_task are the big successes for dead code removal this round. A bunch of small bug fixes are included, as most of the issues reported were small enough that they would not affect bisection so I simply added the fixes and did not fold the fixes into the changes they were fixing. There was a bug that broke coredumps piped to systemd-coredump. I dropped the change that caused that bug and replaced it entirely with something much more restrained. Unfortunately that required some rebasing. Some successes after this set of changes: There are few enough calls to do_exit to audit in a reasonable amount of time. The lifetime of struct kthread now matches the lifetime of struct task, and the pointer to struct kthread is no longer stored in set_child_tid. The flag SIGNAL_GROUP_COREDUMP is removed. The field group_exit_task is removed. Issues where task->exit_code was examined with signal->group_exit_code should been examined were fixed. There are several loosely related changes included because I am cleaning up and if I don't include them they will probably get lost. The original postings of these changes can be found at: https://lkml.kernel.org/r/87a6ha4zsd.fsf@email.froward.int.ebiederm.org https://lkml.kernel.org/r/87bl1kunjj.fsf@email.froward.int.ebiederm.org https://lkml.kernel.org/r/87r19opkx1.fsf_-_@email.froward.int.ebiederm.org I trimmed back the last set of changes to only the obviously correct once. Simply because there was less time for review than I had hoped" * 'signal-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (44 commits) ptrace/m68k: Stop open coding ptrace_report_syscall ptrace: Remove unused regs argument from ptrace_report_syscall ptrace: Remove second setting of PT_SEIZED in ptrace_attach taskstats: Cleanup the use of task->exit_code exit: Use the correct exit_code in /proc/<pid>/stat exit: Fix the exit_code for wait_task_zombie exit: Coredumps reach do_group_exit exit: Remove profile_handoff_task exit: Remove profile_task_exit & profile_munmap signal: clean up kernel-doc comments signal: Remove the helper signal_group_exit signal: Rename group_exit_task group_exec_task coredump: Stop setting signal->group_exit_task signal: Remove SIGNAL_GROUP_COREDUMP signal: During coredumps set SIGNAL_GROUP_EXIT in zap_process signal: Make coredump handling explicit in complete_signal signal: Have prepare_signal detect coredumps using signal->core_state signal: Have the oom killer detect coredumps using signal->core_state exit: Move force_uaccess back into do_exit exit: Guarantee make_task_dead leaks the tsk when calling do_task_exit ...
2022-01-07cifs: avoid race during socket reconnect between send and recvShyam Prasad N
When a TCP connection gets reestablished by the sender in cifs_reconnect, There is a chance for race condition with demultiplex thread waiting in cifs_readv_from_socket on the old socket. It will now return -ECONNRESET. This condition is handled by comparing socket pointer before and after sock_recvmsg. If the socket pointer has changed, we should not call cifs_reconnect again, but instead retry with new socket. Also fixed another bug in my prev mchan commits. We should always reestablish session (even if binding) on a channel that needs reconnection. Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-07cifs: maintain a state machine for tcp/smb/tcon sessionsShyam Prasad N
If functions like cifs_negotiate_protocol, cifs_setup_session, cifs_tree_connect are called in parallel on different channels, each of these will be execute the requests. This maybe unnecessary in some cases, and only the first caller may need to do the work. This is achieved by having more states for the tcp/smb/tcon session status fields. And tracking the state of reconnection based on the state machine. For example: for tcp connections: CifsNew/CifsNeedReconnect -> CifsNeedNegotiate -> CifsInNegotiate -> CifsNeedSessSetup -> CifsInSessSetup -> CifsGood for smb sessions: CifsNew/CifsNeedReconnect -> CifsGood for tcon: CifsNew/CifsNeedReconnect -> CifsInFilesInvalidate -> CifsNeedTcon -> CifsInTcon -> CifsGood If any channel reconnect sees that it's in the middle of transition to CifsGood, then they can skip the function. Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-07cifs: take cifs_tcp_ses_lock for status checksShyam Prasad N
While checking/updating status for tcp ses, smb ses or tcon, we take GlobalMid_Lock. This doesn't make any sense. Replaced it with cifs_tcp_ses_lock. Ideally, we should take a spin lock per struct. But since tcp ses, smb ses and tcon objects won't add up to a lot, I think there should not be too much contention. Also, in few other places, these are checked without locking. Added locking for these. Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-02cifs: reconnect only the connection and not smb session where possibleShyam Prasad N
With the new per-channel bitmask for reconnect, we have an option to reconnect the tcp session associated with the channel without reconnecting the smb session. i.e. if there are still channels to operate on, we can continue to use the smb session and tcon. However, there are cases where it makes sense to reconnect the smb session even when there are active channels underneath. For example for SMB session expiry. With this patch, we'll have an option to do either, and use the correct option for specific cases. Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-02cifs: use the chans_need_reconnect bitmap for reconnect statusShyam Prasad N
We use the concept of "binding" when one of the secondary channel is in the process of connecting/reconnecting to the server. Till this binding process completes, and the channel is bound to an existing session, we redirect traffic from other established channels on the binding channel, effectively blocking all traffic till individual channels get reconnected. With my last set of commits, we can get rid of this binding serialization. We now have a bitmap of connection states for each channel. We will use this bitmap instead for tracking channel status. Having a bitmap also now enables us to keep the session alive, as long as even a single channel underneath is alive. Unfortunately, this also meant that we need to supply the tcp connection info for the channel during all negotiate and session setup functions. These changes have resulted in a slightly bigger code churn. However, I expect perf and robustness improvements in the mchan scenario after this change. Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-02cifs: track individual channel status using chans_need_reconnectShyam Prasad N
We needed a way to identify the channels under the smb session which are in reconnect, so that the traffic to other channels can continue. So I replaced the bool need_reconnect with a bitmask identifying all the channels that need reconnection (named chans_need_reconnect). When a channel needs reconnection, the bit corresponding to the index of the server in ses->chans is used to set this bitmask. Checking if no channels or all the channels need reconnect then becomes very easy. Also wrote some helper macros for checking and setting the bits. Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-12-17cifs: ignore resource_id while getting fscache super cookieShyam Prasad N
We have a cyclic dependency between fscache super cookie and root inode cookie. The super cookie relies on tcon->resource_id, which gets populated from the root inode number. However, fetching the root inode initializes inode cookie as a child of super cookie, which is yet to be populated. resource_id is only used as auxdata to check the validity of super cookie. We can completely avoid setting resource_id to remove the circular dependency. Since vol creation time and vol serial numbers are used for auxdata, we should be fine. Additionally, there will be auxiliary data check for each inode cookie as well. Fixes: 5bf91ef03d98 ("cifs: wait for tcon resource_id before getting fscache super") CC: David Howells <dhowells@redhat.com> Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-12-13exit: Rename module_put_and_exit to module_put_and_kthread_exitEric W. Biederman
Update module_put_and_exit to call kthread_exit instead of do_exit. Change the name to reflect this change in functionality. All of the users of module_put_and_exit are causing the current kthread to exit so this change makes it clear what is happening. There is no functional change. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2021-12-03cifs: add server conn_id to fscache client cookieShyam Prasad N
The fscache client cookie uses the server address (and port) as the cookie key. This is a problem when nosharesock is used. Two different connections will use duplicate cookies. Avoid this by adding server->conn_id to the key, so that it's guaranteed that cookie will not be duplicated. Also, for secondary channels of a session, copy the fscache pointer from the primary channel. The primary channel is guaranteed not to go away as long as secondary channels are in use. Also addresses minor problem found by kernel test robot. Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-12-03cifs: wait for tcon resource_id before getting fscache superShyam Prasad N
The logic for initializing tcon->resource_id is done inside cifs_root_iget. fscache super cookie relies on this for aux data. So we need to push the fscache initialization to this later point during mount. Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-12-03cifs: fix missed refcounting of ipc tconPaulo Alcantara
Fix missed refcounting of IPC tcon used for getting domain-based DFS root referrals. We want to keep it alive as long as mount is active and can be refreshed. For standalone DFS root referrals it wouldn't be a problem as the client ends up having an IPC tcon for both mount and cache. Fixes: c88f7dcd6d64 ("cifs: support nested dfs links over reconnect") Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Reviewed-by: Enzo Matsumiya <ematsumiya@suse.de> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-23cifs: nosharesock should be set on new serverShyam Prasad N
Recent fix to maintain a nosharesock state on the server struct caused a regression. It updated this field in the old tcp session, and not the new one. This caused the multichannel scenario to misbehave. Fixes: c9f1c19cf7c5 (cifs: nosharesock should not share socket with future sessions) Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-16cifs: introduce cifs_ses_mark_for_reconnect() helperPaulo Alcantara
Use new cifs_ses_mark_for_reconnect() helper to mark all session channels for reconnect instead of duplicating it in different places. Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-16cifs: protect srv_count with cifs_tcp_ses_lockSteve French
Updates to the srv_count field are protected elsewhere with the cifs_tcp_ses_lock spinlock. Add one missing place (cifs_get_tcp_sesion). CC: Shyam Prasad N <sprasad@microsoft.com> Addresses-Coverity: 1494149 ("Data Race Condition") Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-12cifs: do not duplicate fscache cookie for secondary channelsShyam Prasad N
We allocate index cookies for each connection from the client. However, we don't need this index for each channel in case of multichannel. So making sure that we avoid creating duplicate cookies by instantiating only for primary channel. Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-12cifs: connect individual channel servers to primary channel serverShyam Prasad N
Today, we don't have any way to get the smb session for any of the secondary channels. Introducing a pointer to the primary server from server struct of any secondary channel. The value will be NULL for the server of the primary channel. This will enable us to get the smb session for any channel. This will be needed for some of the changes that I'm planning to make soon. Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-12cifs: protect session channel fields with chan_lockShyam Prasad N
Introducing a new spin lock to protect all the channel related fields in a cifs_ses struct. This lock should be taken whenever dealing with the channel fields, and should be held only for very short intervals which will not sleep. Currently, all channel related fields in cifs_ses structure are protected by session_mutex. However, this mutex is held for long periods (sometimes while waiting for a reply from server). This makes the codepath quite tricky to change. Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-12cifs: do not negotiate session if session already existsShyam Prasad N
In cifs_get_smb_ses, if we find an existing matching session, we should not send a negotiate request for the session if a session reconnect is not necessary. Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-12smb3: do not setup the fscache_super_cookie until fsinfo initializedSteve French
We were calling cifs_fscache_get_super_cookie after tcon but before we queried the info (QFS_Info) we need to initialize the cookie properly. Also includes an additional check suggested by Paulo to make sure we don't initialize super cookie twice. Suggested-by: David Howells <dhowells@redhat.com> Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-12cifs: fix potential use-after-free bugsPaulo Alcantara
Ensure that share and prefix variables are set to NULL after kfree() when looping through DFS targets in __tree_connect_dfs_target(). Also, get rid of @ref in __tree_connect_dfs_target() and just pass a boolean to indicate whether we're handling link targets or not. Fixes: c88f7dcd6d64 ("cifs: support nested dfs links over reconnect") Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-12cifs: release lock earlier in dequeue_mid error caseSteve French
In dequeue_mid we can log an error while holding a spinlock, GlobalMid_Lock. Coverity notes that the error logging also grabs a lock so it is cleaner (and a bit safer) to release the GlobalMid_Lock before logging the warning. Addresses-Coverity: 1507573 ("Thread deadlock") Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-10smb3: remove trivial dfs compile warningSteve French
Fix warning caused by recent changes to the dfs code: symbol 'tree_connect_dfs_target' was not declared. Should it be static? Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-10cifs: support nested dfs links over reconnectPaulo Alcantara
Mounting a dfs link that has nested links was already supported at mount(2), so make it work over reconnect as well. Make the following case work: * mount //root/dfs/link /mnt -o ... - final share: /server/share * in server settings - change target folder of /root/dfs/link3 to /server/share2 - change target folder of /root/dfs/link2 to /root/dfs/link3 - change target folder of /root/dfs/link to /root/dfs/link2 * mount -o remount,... /mnt - refresh all dfs referrals - mark current connection for failover - cifs_reconnect() reconnects to root server - tree_connect() * checks that /root/dfs/link2 is a link, then chase it * checks that root/dfs/link3 is a link, then chase it * finally tree connect to /server/share2 If the mounted share is no longer accessible and a reconnect had been triggered, the client will retry it from both last referral path (/root/dfs/link3) and original referral path (/root/dfs/link). Any new referral paths found while chasing dfs links over reconnect, it will be updated to TCP_Server_Info::leaf_fullpath, accordingly. Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-09cifs: set a minimum of 120s for next dns resolutionPaulo Alcantara
With commit 506c1da44fee ("cifs: use the expiry output of dns_query to schedule next resolution") and after triggering the first reconnect, the next async dns resolution of tcp server's hostname would be scheduled based on dns_resolver's key expiry default, which happens to default to 5s on most systems that use key.dns_resolver for upcall. As per key.dns_resolver.conf(5): default_ttl=<number> The number of seconds to set as the expiration on a cached record. This will be overridden if the program manages to re- trieve TTL information along with the addresses (if, for exam- ple, it accesses the DNS directly). The default is 5 seconds. The value must be in the range 1 to INT_MAX. Make the next async dns resolution no shorter than 120s as we do not want to be upcalling too often. Cc: stable@vger.kernel.org Fixes: 506c1da44fee ("cifs: use the expiry output of dns_query to schedule next resolution") Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Reviewed-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-09cifs: split out dfs code from cifs_reconnect()Paulo Alcantara
Make two separate functions that handle dfs and non-dfs reconnect logics since cifs_reconnect() became way too complex to handle both. While at it, add some documentation. Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Reviewed-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-09cifs: convert list_for_each to entry variantPaulo Alcantara
Convert list_for_each{,_safe} to list_for_each_entry{,_safe} in cifs_mark_tcp_ses_conns_for_reconnect() function. Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Reviewed-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>