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path: root/fs/cifs/connect.c
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2022-06-24cifs: update cifs_ses::ip_addr after failoverPaulo Alcantara
cifs_ses::ip_addr wasn't being updated in cifs_session_setup() when reconnecting SMB sessions thus returning wrong value in /proc/fs/cifs/DebugData. Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Cc: stable@kernel.org Signed-off-by: Steve French <stfrench@microsoft.com>
2022-06-24cifs: avoid deadlocks while updating ifaceShyam Prasad N
We use cifs_tcp_ses_lock to protect a lot of things. Not only does it protect the lists of connections, sessions, tree connects, open file lists, etc., we also use it to protect some fields in each of it's entries. In this case, cifs_mark_ses_for_reconnect takes the cifs_tcp_ses_lock to traverse the lists, and then calls cifs_update_iface. However, that can end up calling cifs_put_tcp_session, which picks up the same lock again. Avoid this by taking a ref for the session, drop the lock, and then call update iface. Also, in cifs_update_iface, avoid nested locking of iface_lock and chan_lock, as much as possible. When unavoidable, we need to pick iface_lock first. Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-06-22cifs: periodically query network interfaces from serverShyam Prasad N
Currently, we only query the server for network interfaces information at the time of mount, and never afterwards. This can be a problem, especially for services like Azure, where the IP address of the channel endpoints can change over time. With this change, we schedule a 600s polling of this info from the server for each tree connect. An alternative for periodic polling was to do this only at the time of reconnect. But this could delay the reconnect time slightly. Also, there are some challenges w.r.t how we have cifs_reconnect implemented today. Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-06-22cifs: during reconnect, update interface if necessaryShyam Prasad N
Going forward, the plan is to periodically query the server for it's interfaces (when multichannel is enabled). This change allows checking for inactive interfaces during reconnect, and reconnect to a new interface if necessary. Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-06-22cifs: change iface_list from array to sorted linked listShyam Prasad N
A server's published interface list can change over time, and needs to be updated. We've storing iface_list as a simple array, which makes it difficult to manipulate an existing list. With this change, iface_list is modified into a linked list of interfaces, which is kept sorted by speed. Also added a reference counter for an iface entry, so that each channel can maintain a backpointer to the iface and drop it easily when needed. Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-06-10cifs: populate empty hostnames for extra channelsShyam Prasad N
Currently, the secondary channels of a multichannel session also get hostname populated based on the info in primary channel. However, this will end up with a wrong resolution of hostname to IP address during reconnect. This change fixes this by not populating hostname info for all secondary channels. Fixes: 5112d80c162f ("cifs: populate server_hostname for extra channels") Cc: stable@vger.kernel.org Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-06-01cifs: fix potential deadlock in direct reclaimVincent Whitchurch
The srv_mutex is used during writeback so cifs should ensure that allocations done when that mutex is held are done with GFP_NOFS, to avoid having direct reclaim ending up waiting for the same mutex and causing a deadlock. This is detected by lockdep with the splat below: ====================================================== WARNING: possible circular locking dependency detected 5.18.0 #70 Not tainted ------------------------------------------------------ kswapd0/49 is trying to acquire lock: ffff8880195782e0 (&tcp_ses->srv_mutex){+.+.}-{3:3}, at: compound_send_recv but task is already holding lock: ffffffffa98e66c0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (fs_reclaim){+.+.}-{0:0}: fs_reclaim_acquire kmem_cache_alloc_trace __request_module crypto_alg_mod_lookup crypto_alloc_tfm_node crypto_alloc_shash cifs_alloc_hash smb311_crypto_shash_allocate smb311_update_preauth_hash compound_send_recv cifs_send_recv SMB2_negotiate smb2_negotiate cifs_negotiate_protocol cifs_get_smb_ses cifs_mount cifs_smb3_do_mount smb3_get_tree vfs_get_tree path_mount __x64_sys_mount do_syscall_64 entry_SYSCALL_64_after_hwframe -> #0 (&tcp_ses->srv_mutex){+.+.}-{3:3}: __lock_acquire lock_acquire __mutex_lock mutex_lock_nested compound_send_recv cifs_send_recv SMB2_write smb2_sync_write cifs_write cifs_writepage_locked cifs_writepage shrink_page_list shrink_lruvec shrink_node balance_pgdat kswapd kthread ret_from_fork other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(&tcp_ses->srv_mutex); lock(fs_reclaim); lock(&tcp_ses->srv_mutex); *** DEADLOCK *** 1 lock held by kswapd0/49: #0: ffffffffa98e66c0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat stack backtrace: CPU: 2 PID: 49 Comm: kswapd0 Not tainted 5.18.0 #70 Call Trace: <TASK> dump_stack_lvl dump_stack print_circular_bug.cold check_noncircular __lock_acquire lock_acquire __mutex_lock mutex_lock_nested compound_send_recv cifs_send_recv SMB2_write smb2_sync_write cifs_write cifs_writepage_locked cifs_writepage shrink_page_list shrink_lruvec shrink_node balance_pgdat kswapd kthread ret_from_fork </TASK> Fix this by using the memalloc_nofs_save/restore APIs around the places where the srv_mutex is held. Do this in a wrapper function for the lock/unlock of the srv_mutex, and rename the srv_mutex to avoid missing call sites in the conversion. Note that there is another lockdep warning involving internal crypto locks, which was masked by this problem and is visible after this fix, see the discussion in this thread: https://lore.kernel.org/all/20220523123755.GA13668@axis.com/ Link: https://lore.kernel.org/r/CANT5p=rqcYfYMVHirqvdnnca4Mo+JQSw5Qu12v=kPfpk5yhhmg@mail.gmail.com/ Reported-by: Shyam Prasad N <nspmangalore@gmail.com> Suggested-by: Lars Persson <larper@axis.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> Reviewed-by: Enzo Matsumiya <ematsumiya@suse.de> Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-05-31cifs: remove repeated debug message on cifs_put_smb_ses()Enzo Matsumiya
Similar message is printed a few lines later in the same function Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-05-25cifs: fix ntlmssp on old serversPaulo Alcantara
Some older servers seem to require the workstation name during ntlmssp to be at most 15 chars (RFC1001 name length), so truncate it before sending when using insecure dialects. Link: https://lore.kernel.org/r/e6837098-15d9-acb6-7e34-1923cf8c6fe1@winds.org Reported-by: Byron Stanoszek <gandalf@winds.org> Tested-by: Byron Stanoszek <gandalf@winds.org> Fixes: 49bd49f983b5 ("cifs: send workstation name during ntlmssp session setup") Cc: stable@vger.kernel.org Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-05-24cifs: avoid parallel session setups on same channelShyam Prasad N
After allowing channels to reconnect in parallel, it now becomes important to take care that multiple processes do not call negotiate/session setup in parallel on the same channel. This change avoids that by marking a channel as "in_reconnect". During session setup if the channel in question has this flag set, we return immediately. Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-05-24cifs: use new enum for ses_statusShyam Prasad N
ses->status today shares statusEnum with server->tcpStatus. This has been confusing, and tcon->status has deviated to use a new enum. Follow suit and use new enum for ses_status as well. Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-05-24cifs: do not use tcpStatus after negotiate completesShyam Prasad N
Recent changes to multichannel to allow channel reconnects to work in parallel and independent of each other did so by making use of tcpStatus for the connection, and status for the session. However, this did not take into account the multiuser scenario, where same connection is used by multiple connections. However, tcpStatus should be tracked only till the end of negotiate exchange, and not used for session setup. This change fixes this. Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-05-23smb3: add mount parm nosparseSteve French
To reduce risk of applications breaking that mount to servers with only partial sparse file support, add optional mount parm "nosparse" which disables setting files sparse (and thus will return EOPNOTSUPP on certain fallocate operations). Acked-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-05-23cifs: fix minor compile warningSteve French
Add ifdef around nodfs variable from patch: "cifs: don't call cifs_dfs_query_info_nonascii_quirk() if nodfs was set" which is unused when CONFIG_DFS_UPCALL is not set. Signed-off-by: Steve French <stfrench@microsoft.com>
2022-05-20cifs: print TIDs as hexEnzo Matsumiya
Makes these debug messages easier to read Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de> Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-05-20cifs: return ENOENT for DFS lookup_cache_entry()Enzo Matsumiya
EEXIST didn't make sense to use when dfs_cache_find() couldn't find a cache entry nor retrieve a referral target. It also doesn't make sense cifs_dfs_query_info_nonascii_quirk() to emulate ENOENT anymore. Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de> Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-05-20cifs: don't call cifs_dfs_query_info_nonascii_quirk() if nodfs was setEnzo Matsumiya
Also return EOPNOTSUPP if path is remote but nodfs was set. Fixes: a2809d0e1696 ("cifs: quirk for STATUS_OBJECT_NAME_INVALID returned for non-ASCII dfs refs") Cc: stable@vger.kernel.org Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-04-20cifs: use correct lock type in cifs_reconnect()Paulo Alcantara
TCP_Server_Info::origin_fullpath and TCP_Server_Info::leaf_fullpath are protected by refpath_lock mutex and not cifs_tcp_ses_lock spinlock. Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Cc: stable@vger.kernel.org Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-04-20cifs: fix NULL ptr dereference in refresh_mounts()Paulo Alcantara
Either mount(2) or automount might not have server->origin_fullpath set yet while refresh_cache_worker() is attempting to refresh DFS referrals. Add missing NULL check and locking around it. This fixes bellow crash: [ 1070.276835] general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN NOPTI [ 1070.277676] KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] [ 1070.278219] CPU: 1 PID: 8506 Comm: kworker/u8:1 Not tainted 5.18.0-rc3 #10 [ 1070.278701] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.15.0-0-g2dd4b9b-rebuilt.opensuse.org 04/01/2014 [ 1070.279495] Workqueue: cifs-dfscache refresh_cache_worker [cifs] [ 1070.280044] RIP: 0010:strcasecmp+0x34/0x150 [ 1070.280359] Code: 00 00 00 fc ff df 41 54 55 48 89 fd 53 48 83 ec 10 eb 03 4c 89 fe 48 89 ef 48 83 c5 01 48 89 f8 48 89 fa 48 c1 e8 03 83 e2 07 <42> 0f b6 04 28 38 d0 7f 08 84 c0 0f 85 bc 00 00 00 0f b6 45 ff 44 [ 1070.281729] RSP: 0018:ffffc90008367958 EFLAGS: 00010246 [ 1070.282114] RAX: 0000000000000000 RBX: dffffc0000000000 RCX: 0000000000000000 [ 1070.282691] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 1070.283273] RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff873eda27 [ 1070.283857] R10: ffffc900083679a0 R11: 0000000000000001 R12: ffff88812624c000 [ 1070.284436] R13: dffffc0000000000 R14: ffff88810e6e9a88 R15: ffff888119bb9000 [ 1070.284990] FS: 0000000000000000(0000) GS:ffff888151200000(0000) knlGS:0000000000000000 [ 1070.285625] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1070.286100] CR2: 0000561a4d922418 CR3: 000000010aecc000 CR4: 0000000000350ee0 [ 1070.286683] Call Trace: [ 1070.286890] <TASK> [ 1070.287070] refresh_cache_worker+0x895/0xd20 [cifs] [ 1070.287475] ? __refresh_tcon.isra.0+0xfb0/0xfb0 [cifs] [ 1070.287905] ? __lock_acquire+0xcd1/0x6960 [ 1070.288247] ? is_dynamic_key+0x1a0/0x1a0 [ 1070.288591] ? lockdep_hardirqs_on_prepare+0x410/0x410 [ 1070.289012] ? lock_downgrade+0x6f0/0x6f0 [ 1070.289318] process_one_work+0x7bd/0x12d0 [ 1070.289637] ? worker_thread+0x160/0xec0 [ 1070.289970] ? pwq_dec_nr_in_flight+0x230/0x230 [ 1070.290318] ? _raw_spin_lock_irq+0x5e/0x90 [ 1070.290619] worker_thread+0x5ac/0xec0 [ 1070.290891] ? process_one_work+0x12d0/0x12d0 [ 1070.291199] kthread+0x2a5/0x350 [ 1070.291430] ? kthread_complete_and_exit+0x20/0x20 [ 1070.291770] ret_from_fork+0x22/0x30 [ 1070.292050] </TASK> [ 1070.292223] Modules linked in: bpfilter cifs cifs_arc4 cifs_md4 [ 1070.292765] ---[ end trace 0000000000000000 ]--- [ 1070.293108] RIP: 0010:strcasecmp+0x34/0x150 [ 1070.293471] Code: 00 00 00 fc ff df 41 54 55 48 89 fd 53 48 83 ec 10 eb 03 4c 89 fe 48 89 ef 48 83 c5 01 48 89 f8 48 89 fa 48 c1 e8 03 83 e2 07 <42> 0f b6 04 28 38 d0 7f 08 84 c0 0f 85 bc 00 00 00 0f b6 45 ff 44 [ 1070.297718] RSP: 0018:ffffc90008367958 EFLAGS: 00010246 [ 1070.298622] RAX: 0000000000000000 RBX: dffffc0000000000 RCX: 0000000000000000 [ 1070.299428] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 1070.300296] RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff873eda27 [ 1070.301204] R10: ffffc900083679a0 R11: 0000000000000001 R12: ffff88812624c000 [ 1070.301932] R13: dffffc0000000000 R14: ffff88810e6e9a88 R15: ffff888119bb9000 [ 1070.302645] FS: 0000000000000000(0000) GS:ffff888151200000(0000) knlGS:0000000000000000 [ 1070.303462] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1070.304131] CR2: 0000561a4d922418 CR3: 000000010aecc000 CR4: 0000000000350ee0 [ 1070.305004] Kernel panic - not syncing: Fatal exception [ 1070.305711] Kernel Offset: disabled [ 1070.305971] ---[ end Kernel panic - not syncing: Fatal exception ]--- Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Cc: stable@vger.kernel.org Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-04-08cifs: Split the smb3_add_credits tracepointDavid Howells
Split the smb3_add_credits tracepoint to make it more obvious when looking at the logs which line corresponds to what credit change. Also add a tracepoint for credit overflow when it's being added back. Note that it might be better to add another field to the tracepoint for the information rather than splitting it. It would also be useful to store the MID potentially, though that isn't available when the credits are first obtained. Signed-off-by: David Howells <dhowells@redhat.com> cc: Shyam Prasad N <nspmangalore@gmail.com> cc: Rohith Surabattula <rohiths.msft@gmail.com> cc: linux-cifs@vger.kernel.org Acked-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Reviewed-by: Enzo Matsumiya <ematsumiya@suse.de> Signed-off-by: Steve French <stfrench@microsoft.com>
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>
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