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* smb3: fix crediting for compounding when only one request in flightPavel Shilovsky2021-02-051-3/+15
| | | | | | | | | | | | | | | | | | Currently we try to guess if a compound request is going to succeed waiting for credits or not based on the number of requests in flight. This approach doesn't work correctly all the time because there may be only one request in flight which is going to bring multiple credits satisfying the compound request. Change the behavior to fail a request only if there are no requests in flight at all and proceed waiting for credits otherwise. Cc: <stable@vger.kernel.org> # 5.1+ Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Reviewed-by: Tom Talpey <tom@talpey.com> Reviewed-by: Shyam Prasad N <nspmangalore@gmail.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* cifs: do not fail __smb_send_rqst if non-fatal signals are pendingRonnie Sahlberg2021-01-231-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | RHBZ 1848178 The original intent of returning an error in this function in the patch: "CIFS: Mask off signals when sending SMB packets" was to avoid interrupting packet send in the middle of sending the data (and thus breaking an SMB connection), but we also don't want to fail the request for non-fatal signals even before we have had a chance to try to send it (the reported problem could be reproduced e.g. by exiting a child process when the parent process was in the midst of calling futimens to update a file's timestamps). In addition, since the signal may remain pending when we enter the sending loop, we may end up not sending the whole packet before TCP buffers become full. In this case the code returns -EINTR but what we need here is to return -ERESTARTSYS instead to allow system calls to be restarted. Fixes: b30c74c73c78 ("CIFS: Mask off signals when sending SMB packets") Cc: stable@vger.kernel.org # v5.1+ Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* cifs: Tracepoints and logs for tracing credit changes.Shyam Prasad N2020-12-151-0/+15
| | | | | | | | | | | | | | There is at least one suspected bug in crediting changes in cifs.ko which has come up a few times in the discussions and in a customer case. This change adds tracepoints to the code which modifies the server credit values in any way. The goal is to be able to track the changes to the credit values of the session to be able to catch when there is a crediting bug. Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* cifs: allow syscalls to be restarted in __smb_send_rqst()Paulo Alcantara2020-11-301-2/+2
| | | | | | | | | | | | | | | | | | | | | | | A customer has reported that several files in their multi-threaded app were left with size of 0 because most of the read(2) calls returned -EINTR and they assumed no bytes were read. Obviously, they could have fixed it by simply retrying on -EINTR. We noticed that most of the -EINTR on read(2) were due to real-time signals sent by glibc to process wide credential changes (SIGRT_1), and its signal handler had been established with SA_RESTART, in which case those calls could have been automatically restarted by the kernel. Let the kernel decide to whether or not restart the syscalls when there is a signal pending in __smb_send_rqst() by returning -ERESTARTSYS. If it can't, it will return -EINTR anyway. Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz> CC: Stable <stable@vger.kernel.org> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* smb3: add dynamic trace point to trace when credits obtainedSteve French2020-10-201-2/+3
| | | | | | | | | | | | | | | SMB3 crediting is used for flow control, and it can be useful to trace for problem determination how many credits were acquired and for which operation. Here is an example ("trace-cmd record -e *add_credits"): cifsd-9522    [010] ....  5995.202712: smb3_add_credits: server=localhost current_mid=0x12 credits=373 credits_to_add=10 cifsd-9522    [010] ....  5995.204040: smb3_add_credits: server=localhost current_mid=0x15 credits=400 credits_to_add=30 Reviewed-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* cifs`: handle ERRBaduid for SMB1Roberto Bergantinos Corpas2020-08-021-1/+1
| | | | | | | | | | | | | | | If server returns ERRBaduid but does not reset transport connection, we'll keep sending command with a non-valid UID for the server as long as transport is healthy, without actually recovering. This have been observed on the field. This patch adds ERRBaduid handling so that we set CifsNeedReconnect. map_and_check_smb_error() can be modified to extend use cases. Signed-off-by: Roberto Bergantinos Corpas <rbergant@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
* cifs: prevent truncation from long to int in wait_for_free_creditsRonnie Sahlberg2020-07-011-1/+1
| | | | | | | | | The wait_event_... defines evaluate to long so we should not assign it an int as this may truncate the value. Reported-by: Marshall Midden <marshallmidden@gmail.com> Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* Merge tag '5.8-rc-smb3-fixes-part-1' of git://git.samba.org/sfrench/cifs-2.6Linus Torvalds2020-06-051-30/+45
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull cifs updates from Steve French: "22 changesets, 2 for stable. Includes big performance improvement for large i/o when using multichannel, also includes DFS fixes" * tag '5.8-rc-smb3-fixes-part-1' of git://git.samba.org/sfrench/cifs-2.6: (22 commits) cifs: update internal module version number cifs: multichannel: try to rebind when reconnecting a channel cifs: multichannel: use pointer for binding channel smb3: remove static checker warning cifs: multichannel: move channel selection above transport layer cifs: multichannel: always zero struct cifs_io_parms cifs: dump Security Type info in DebugData smb3: fix incorrect number of credits when ioctl MaxOutputResponse > 64K smb3: default to minimum of two channels when multichannel specified cifs: multichannel: move channel selection in function cifs: fix minor typos in comments and log messages smb3: minor update to compression header definitions cifs: minor fix to two debug messages cifs: Standardize logging output smb3: Add new parm "nodelete" cifs: move some variables off the stack in smb2_ioctl_query_info cifs: reduce stack use in smb2_compound_op cifs: get rid of unused parameter in reconn_setup_dfs_targets() cifs: handle hostnames that resolve to same ip in failover cifs: set up next DFS target before generic_ip_connect() ...
| * cifs: multichannel: move channel selection above transport layerAurelien Aptel2020-06-041-7/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move the channel (TCP_Server_Info*) selection from the tranport layer to higher in the call stack so that: - credit handling is done with the server that will actually be used to send. * ->wait_mtu_credit * ->set_credits / set_credits * ->add_credits / add_credits * add_credits_and_wake_if - potential reconnection (smb2_reconnect) done when initializing a request is checked and done with the server that will actually be used to send. To do this: - remove the cifs_pick_channel() call out of compound_send_recv() - select channel and pass it down by adding a cifs_pick_channel(ses) call in: - smb311_posix_mkdir - SMB2_open - SMB2_ioctl - __SMB2_close - query_info - SMB2_change_notify - SMB2_flush - smb2_async_readv (if none provided in context param) - SMB2_read (if none provided in context param) - smb2_async_writev (if none provided in context param) - SMB2_write (if none provided in context param) - SMB2_query_directory - send_set_info - SMB2_oplock_break - SMB311_posix_qfs_info - SMB2_QFS_info - SMB2_QFS_attr - smb2_lockv - SMB2_lease_break - smb2_compound_op - smb2_set_ea - smb2_ioctl_query_info - smb2_query_dir_first - smb2_query_info_comound - smb2_query_symlink - cifs_writepages - cifs_write_from_iter - cifs_send_async_read - cifs_read - cifs_readpages - add TCP_Server_Info *server param argument to: - cifs_send_recv - compound_send_recv - SMB2_open_init - SMB2_query_info_init - SMB2_set_info_init - SMB2_close_init - SMB2_ioctl_init - smb2_iotcl_req_init - SMB2_query_directory_init - SMB2_notify_init - SMB2_flush_init - build_qfs_info_req - smb2_hdr_assemble - smb2_reconnect - fill_small_buf - smb2_plain_req_init - __smb2_plain_req_init The read/write codepath is different than the rest as it is using pages, io iterators and async calls. To deal with those we add a server pointer in the cifs_writedata/cifs_readdata/cifs_io_parms context struct and set it in: - cifs_writepages (wdata) - cifs_write_from_iter (wdata) - cifs_readpages (rdata) - cifs_send_async_read (rdata) The [rw]data->server pointer is eventually copied to cifs_io_parms->server to pass it down to SMB2_read/SMB2_write. If SMB2_read/SMB2_write is called from a different place that doesn't set the server field it will pick a channel. Some places do not pick a channel and just use ses->server or cifs_ses_server(ses). All cifs_ses_server(ses) calls are in codepaths involving negprot/sess.setup. - SMB2_negotiate (binding channel) - SMB2_sess_alloc_buffer (binding channel) - SMB2_echo (uses provided one) - SMB2_logoff (uses master) - SMB2_tdis (uses master) (list not exhaustive) Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
| * cifs: multichannel: move channel selection in functionAurelien Aptel2020-06-021-11/+27
| | | | | | | | | | | | | | This commit moves channel picking code in separate function. Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
| * cifs: Standardize logging outputJoe Perches2020-06-011-13/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use pr_fmt to standardize all logging for fs/cifs. Some logging output had no CIFS: specific prefix. Now all output has one of three prefixes: o CIFS: o CIFS: VFS: o Root-CIFS: Miscellanea: o Convert printks to pr_<level> o Neaten macro definitions o Remove embedded CIFS: prefixes from formats o Convert "illegal" to "invalid" o Coalesce formats o Add missing '\n' format terminations o Consolidate multiple cifs_dbg continuations into single calls o More consistent use of upper case first word output logging o Multiline statement argument alignment and wrapping Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* | tcp: add tcp_sock_set_corkChristoph Hellwig2020-05-281-6/+2
|/ | | | | | | | | Add a helper to directly set the TCP_CORK sockopt from kernel space without going through a fake uaccess. Cleanup the callers to avoid pointless wrappers now that this is a simple function call. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
* cifs: Allocate encryption header through kmallocLong Li2020-03-291-11/+17
| | | | | | | | | | | When encryption is used, smb2_transform_hdr is defined on the stack and is passed to the transport. This doesn't work with RDMA as the buffer needs to be DMA'ed. Fix it by using kmalloc. Signed-off-by: Long Li <longli@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* CIFS: Fix task struct use-after-free on reconnectVincent Whitchurch2020-01-261-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The task which created the MID may be gone by the time cifsd attempts to call the callbacks on MIDs from cifs_reconnect(). This leads to a use-after-free of the task struct in cifs_wake_up_task: ================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x31a0/0x3270 Read of size 8 at addr ffff8880103e3a68 by task cifsd/630 CPU: 0 PID: 630 Comm: cifsd Not tainted 5.5.0-rc6+ #119 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014 Call Trace: dump_stack+0x8e/0xcb print_address_description.constprop.5+0x1d3/0x3c0 ? __lock_acquire+0x31a0/0x3270 __kasan_report+0x152/0x1aa ? __lock_acquire+0x31a0/0x3270 ? __lock_acquire+0x31a0/0x3270 kasan_report+0xe/0x20 __lock_acquire+0x31a0/0x3270 ? __wake_up_common+0x1dc/0x630 ? _raw_spin_unlock_irqrestore+0x4c/0x60 ? mark_held_locks+0xf0/0xf0 ? _raw_spin_unlock_irqrestore+0x39/0x60 ? __wake_up_common_lock+0xd5/0x130 ? __wake_up_common+0x630/0x630 lock_acquire+0x13f/0x330 ? try_to_wake_up+0xa3/0x19e0 _raw_spin_lock_irqsave+0x38/0x50 ? try_to_wake_up+0xa3/0x19e0 try_to_wake_up+0xa3/0x19e0 ? cifs_compound_callback+0x178/0x210 ? set_cpus_allowed_ptr+0x10/0x10 cifs_reconnect+0xa1c/0x15d0 ? generic_ip_connect+0x1860/0x1860 ? rwlock_bug.part.0+0x90/0x90 cifs_readv_from_socket+0x479/0x690 cifs_read_from_socket+0x9d/0xe0 ? cifs_readv_from_socket+0x690/0x690 ? mempool_resize+0x690/0x690 ? rwlock_bug.part.0+0x90/0x90 ? memset+0x1f/0x40 ? allocate_buffers+0xff/0x340 cifs_demultiplex_thread+0x388/0x2a50 ? cifs_handle_standard+0x610/0x610 ? rcu_read_lock_held_common+0x120/0x120 ? mark_lock+0x11b/0xc00 ? __lock_acquire+0x14ed/0x3270 ? __kthread_parkme+0x78/0x100 ? lockdep_hardirqs_on+0x3e8/0x560 ? lock_downgrade+0x6a0/0x6a0 ? lockdep_hardirqs_on+0x3e8/0x560 ? _raw_spin_unlock_irqrestore+0x39/0x60 ? cifs_handle_standard+0x610/0x610 kthread+0x2bb/0x3a0 ? kthread_create_worker_on_cpu+0xc0/0xc0 ret_from_fork+0x3a/0x50 Allocated by task 649: save_stack+0x19/0x70 __kasan_kmalloc.constprop.5+0xa6/0xf0 kmem_cache_alloc+0x107/0x320 copy_process+0x17bc/0x5370 _do_fork+0x103/0xbf0 __x64_sys_clone+0x168/0x1e0 do_syscall_64+0x9b/0xec0 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 0: save_stack+0x19/0x70 __kasan_slab_free+0x11d/0x160 kmem_cache_free+0xb5/0x3d0 rcu_core+0x52f/0x1230 __do_softirq+0x24d/0x962 The buggy address belongs to the object at ffff8880103e32c0 which belongs to the cache task_struct of size 6016 The buggy address is located 1960 bytes inside of 6016-byte region [ffff8880103e32c0, ffff8880103e4a40) The buggy address belongs to the page: page:ffffea000040f800 refcount:1 mapcount:0 mapping:ffff8880108da5c0 index:0xffff8880103e4c00 compound_mapcount: 0 raw: 4000000000010200 ffffea00001f2208 ffffea00001e3408 ffff8880108da5c0 raw: ffff8880103e4c00 0000000000050003 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880103e3900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880103e3980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880103e3a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880103e3a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880103e3b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== This can be reliably reproduced by adding the below delay to cifs_reconnect(), running find(1) on the mount, restarting the samba server while find is running, and killing find during the delay: spin_unlock(&GlobalMid_Lock); mutex_unlock(&server->srv_mutex); + msleep(10000); + cifs_dbg(FYI, "%s: issuing mid callbacks\n", __func__); list_for_each_safe(tmp, tmp2, &retry_list) { mid_entry = list_entry(tmp, struct mid_q_entry, qhead); Fix this by holding a reference to the task struct until the MID is freed. Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com> Signed-off-by: Steve French <stfrench@microsoft.com> CC: Stable <stable@vger.kernel.org> Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
* cifs: try opening channels after mountingAurelien Aptel2019-11-251-1/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After doing mount() successfully we call cifs_try_adding_channels() which will open as many channels as it can. Channels are closed when the master session is closed. The master connection becomes the first channel. ,-------------> global cifs_tcp_ses_list <-------------------------. | | '- TCP_Server_Info <--> TCP_Server_Info <--> TCP_Server_Info <-' (master con) (chan#1 con) (chan#2 con) | ^ ^ ^ v '--------------------|--------------------' cifs_ses | - chan_count = 3 | - chans[] ---------------------' - smb3signingkey[] (master signing key) Note how channel connections don't have sessions. That's because cifs_ses can only be part of one linked list (list_head are internal to the elements). For signing keys, each channel has its own signing key which must be used only after the channel has been bound. While it's binding it must use the master session signing key. For encryption keys, since channel connections do not have sessions attached we must now find matching session by looping over all sessions in smb2_get_enc_key(). Each channel is opened like a regular server connection but at the session setup request step it must set the SMB2_SESSION_REQ_FLAG_BINDING flag and use the session id to bind to. Finally, while sending in compound_send_recv() for requests that aren't negprot, ses-setup or binding related, use a channel by cycling through the available ones (round-robin). Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* cifs: add server paramAurelien Aptel2019-11-251-2/+3
| | | | | | | | | | | As we get down to the transport layer, plenty of functions are passed the session pointer and assume the transport to use is ses->server. Instead we modify those functions to pass (ses, server) so that we can decouple the session from the server. Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* cifs: smbd: Return -EAGAIN when transport is reconnectingLong Li2019-11-251-2/+5
| | | | | | | | | | During reconnecting, the transport may have already been destroyed and is in the process being reconnected. In this case, return -EAGAIN to not fail and to retry this I/O. Signed-off-by: Long Li <longli@microsoft.com> Cc: stable@vger.kernel.org Signed-off-by: Steve French <stfrench@microsoft.com>
* CIFS: Do not miss cancelled OPEN responsesPavel Shilovsky2019-11-251-2/+8
| | | | | | | | | | | | | | | | | | | | When an OPEN command is cancelled we mark a mid as cancelled and let the demultiplex thread process it by closing an open handle. The problem is there is a race between a system call thread and the demultiplex thread and there may be a situation when the mid has been already processed before it is set as cancelled. Fix this by processing cancelled requests when mids are being destroyed which means that there is only one thread referencing a particular mid. Also set mids as cancelled unconditionally on their state. Cc: Stable <stable@vger.kernel.org> Tested-by: Frank Sorenson <sorenson@redhat.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* cifs: rename a variable in SendReceive()Dan Carpenter2019-11-251-1/+1
| | | | | | | | | Smatch gets confused because we sometimes refer to "server->srv_mutex" and sometimes to "sess->server->srv_mutex". They refer to the same lock so let's just make this consistent. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* CIFS: Fix retry mid list corruption on reconnectsPavel Shilovsky2019-10-241-19/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the client hits reconnect it iterates over the mid pending queue marking entries for retry and moving them to a temporary list to issue callbacks later without holding GlobalMid_Lock. In the same time there is no guarantee that mids can't be removed from the temporary list or even freed completely by another thread. It may cause a temporary list corruption: [ 430.454897] list_del corruption. prev->next should be ffff98d3a8f316c0, but was 2e885cb266355469 [ 430.464668] ------------[ cut here ]------------ [ 430.466569] kernel BUG at lib/list_debug.c:51! [ 430.468476] invalid opcode: 0000 [#1] SMP PTI [ 430.470286] CPU: 0 PID: 13267 Comm: cifsd Kdump: loaded Not tainted 5.4.0-rc3+ #19 [ 430.473472] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 [ 430.475872] RIP: 0010:__list_del_entry_valid.cold+0x31/0x55 ... [ 430.510426] Call Trace: [ 430.511500] cifs_reconnect+0x25e/0x610 [cifs] [ 430.513350] cifs_readv_from_socket+0x220/0x250 [cifs] [ 430.515464] cifs_read_from_socket+0x4a/0x70 [cifs] [ 430.517452] ? try_to_wake_up+0x212/0x650 [ 430.519122] ? cifs_small_buf_get+0x16/0x30 [cifs] [ 430.521086] ? allocate_buffers+0x66/0x120 [cifs] [ 430.523019] cifs_demultiplex_thread+0xdc/0xc30 [cifs] [ 430.525116] kthread+0xfb/0x130 [ 430.526421] ? cifs_handle_standard+0x190/0x190 [cifs] [ 430.528514] ? kthread_park+0x90/0x90 [ 430.530019] ret_from_fork+0x35/0x40 Fix this by obtaining extra references for mids being retried and marking them as MID_DELETED which indicates that such a mid has been dequeued from the pending list. Also move mid cleanup logic from DeleteMidQEntry to _cifs_mid_q_entry_release which is called when the last reference to a particular mid is put. This allows to avoid any use-after-free of response buffers. The patch needs to be backported to stable kernels. A stable tag is not mentioned below because the patch doesn't apply cleanly to any actively maintained stable kernel. Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> Reviewed-and-tested-by: David Wysochanski <dwysocha@redhat.com> Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* smb3: display max smb3 requests in flight at any one timeSteve French2019-09-161-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Displayed in /proc/fs/cifs/Stats once for each socket we are connected to. This allows us to find out what the maximum number of requests that had been in flight (at any one time). Note that /proc/fs/cifs/Stats can be reset if you want to look for maximum over a small period of time. Sample output (immediately after mount): Resources in use CIFS Session: 1 Share (unique mount targets): 2 SMB Request/Response Buffer: 1 Pool size: 5 SMB Small Req/Resp Buffer: 1 Pool size: 30 Operations (MIDs): 0 0 session 0 share reconnects Total vfs operations: 5 maximum at one time: 2 Max requests in flight: 2 1) \\localhost\scratch SMBs: 18 Bytes read: 0 Bytes written: 0 ... Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
* cifs: add a debug macro that prints \\server\share for errorsRonnie Sahlberg2019-09-161-2/+2
| | | | | | | | Where we have a tcon available we can log \\server\share as part of the message. Only do this for the VFS log level. Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* cifs: fix dereference on ses before it is null checkedColin Ian King2019-09-161-1/+2
| | | | | | | | | | | | The assignment of pointer server dereferences pointer ses, however, this dereference occurs before ses is null checked and hence we have a potential null pointer dereference. Fix this by only dereferencing ses after it has been null checked. Addresses-Coverity: ("Dereference before null check") Fixes: 2808c6639104 ("cifs: add new debugging macro cifs_server_dbg") Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* cifs: add new debugging macro cifs_server_dbgRonnie Sahlberg2019-09-161-56/+59
| | | | | | | | | | | | which can be used from contexts where we have a TCP_Server_Info *server. This new macro will prepend the debugging string with "Server:<servername> " which will help when debugging issues on hosts with many cifs connections to several different servers. Convert a bunch of cifs_dbg(VFS) calls to cifs_server_dbg(VFS) Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* smb3: minor cleanup of compound_send_recvAurelien Aptel2019-07-071-22/+24
| | | | | | | | | Trivial cleanup. Will make future multichannel code smaller as well. Signed-off-by: Aurelien Aptel <aaptel@suse.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* cifs: use the right include for signal_pending()Ronnie Sahlberg2019-05-121-1/+1
| | | | | | | | This header is actually where signal_pending is defined although either would work. Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* cifs: rename and clarify CIFS_ASYNC_OP and CIFS_NO_RESPRonnie Sahlberg2019-05-071-6/+3
| | | | | | | | | | | | | | | The flags were named confusingly. CIFS_ASYNC_OP now just means that we will not block waiting for credits to become available so we thus rename this to be CIFS_NON_BLOCKING. Change CIFS_NO_RESP to CIFS_NO_RSP_BUF to clarify that we will actually get a response from the server but we will not get/do not want a response buffer. Delete CIFSSMBNotify. This is an SMB1 function that is not used. Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
* cifs: fix credits leak for SMB1 oplock breaksRonnie Sahlberg2019-05-071-5/+5
| | | | | | | | | | | | | | | | For SMB1 oplock breaks we would grab one credit while sending the PDU but we would never relese the credit back since we will never receive a response to this from the server. Eventuallt this would lead to a hang once all credits are leaked. Fix this by defining a new flag CIFS_NO_SRV_RSP which indicates that there is no server response to this command and thus we need to add any credits back immediately after sending the PDU. CC: Stable <stable@vger.kernel.org> #v5.0+ Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* cifs: smbd: take an array of reqeusts when sending upper layer dataLong Li2019-05-071-1/+1
| | | | | | | | | | | To support compounding, __smb_send_rqst() now sends an array of requests to the transport layer. Change smbd_send() to take an array of requests, and send them in as few packets as possible. Signed-off-by: Long Li <longli@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com> CC: Stable <stable@vger.kernel.org>
* SMB3: Track total time spent on roundtrips for each SMB3 commandSteve French2019-05-071-4/+23
| | | | | | Also track minimum and maximum time by command in /proc/fs/cifs/Stats Signed-off-by: Steve French <stfrench@microsoft.com>
* cifs: simplify how we handle credits in compound_send_recv()Ronnie Sahlberg2019-03-141-72/+38
| | | | | | | | | | | | | | | | | Since we can now wait for multiple requests atomically in wait_for_free_request() we can now greatly simplify the handling of the credits in this function. This fixes a potential deadlock where many concurrent compound requests could each have reserved 1 or 2 credits each but are all blocked waiting for the final credits they need to be able to issue the requests to the server. Set a default timeout of 60 seconds for compounded requests. Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
* smb3: add dynamic tracepoint for timeout waiting for creditsSteve French2019-03-141-0/+5
| | | | | | | | | To help debug credit starvation problems where we timeout waiting for server to grant the client credits. Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
* cifs: add a timeout argument to wait_for_free_creditsRonnie Sahlberg2019-03-141-10/+30
| | | | | | | | A negative timeout is the same as the current behaviour, i.e. no timeout. Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
* cifs: prevent starvation in wait_for_free_credits for multi-credit requestsRonnie Sahlberg2019-03-141-0/+28
| | | | | | | | | | | | | | | Reserve the last MAX_COMPOUND credits for any request asking for >1 credit. This is to prevent future compound requests from becoming starved while waiting for potentially many requests is there is a large number of concurrent singe-credit requests. However, we need to protect from servers that are very slow to hand out new credits on new sessions so we only do this IFF there are 2*MAX_COMPOUND (arbitrary) credits already in flight. Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
* cifs: wait_for_free_credits() make it possible to wait for >=1 creditsRonnie Sahlberg2019-03-141-7/+7
| | | | | | | | | Change wait_for_free_credits() to allow waiting for >=1 credits instead of just a single credit. Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
* cifs: pass flags down into wait_for_free_credits()Ronnie Sahlberg2019-03-141-16/+14
| | | | | | Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
* cifs: change wait_for_free_request() to take flags as argumentRonnie Sahlberg2019-03-141-16/+17
| | | | | | | | and compute timeout and optyp from it. Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
* CIFS: Mask off signals when sending SMB packetsPavel Shilovsky2019-03-051-3/+38
| | | | | | | | | | | | | | | | We don't want to break SMB sessions if we receive signals when sending packets through the network. Fix it by masking off signals inside __smb_send_rqst() to avoid partial packet sends due to interrupts. Return -EINTR if a signal is pending and only a part of the packet was sent. Return a success status code if the whole packet was sent regardless of signal being pending or not. This keeps a mid entry for the request in the pending queue and allows the demultiplex thread to handle a response from the server properly. Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* CIFS: Return -EAGAIN instead of -ENOTSOCKPavel Shilovsky2019-03-051-1/+2
| | | | | | | | | | | | When we attempt to send a packet while the demultiplex thread is in the middle of cifs_reconnect() we may end up returning -ENOTSOCK to upper layers. The intent here is to retry the request once the TCP connection is up, so change it to return -EAGAIN instead. The latter error code is retryable and the upper layers will retry the request if needed. Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* CIFS: Try to acquire credits at once for compound requestsPavel Shilovsky2019-03-051-5/+34
| | | | | | | | | | | | | | | | | Currently we get one credit per compound part of the request individually. This may lead to being stuck on waiting for credits if multiple compounded operations happen in parallel. Try acquire credits for all compound parts at once. Return immediately if not enough credits and too few requests are in flight currently thus narrowing the possibility of infinite waiting for credits. The more advance fix is to return right away if not enough credits for the compound request and do not look at the number of requests in flight. The caller should handle such situations by falling back to sequential execution of SMB commands instead of compounding. Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* CIFS: Check for reconnects before sending compound requestsPavel Shilovsky2019-03-051-2/+36
| | | | | | | | | The reconnect might have happended after we obtained credits and before we acquired srv_mutex. Check for that under the mutex and retry a sync operation if the reconnect is detected. Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* CIFS: Check for reconnects before sending async requestsPavel Shilovsky2019-03-051-2/+16
| | | | | | | | | The reconnect might have happended after we obtained credits and before we acquired srv_mutex. Check for that under the mutex and retry an async operation if the reconnect is detected. Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* CIFS: Respect reconnect in non-MTU credits calculationsPavel Shilovsky2019-03-051-18/+36
| | | | | | | | | | Every time after a session reconnect we don't need to account for credits obtained in previous sessions. Make use of the recently added cifs_credits structure to properly calculate credits for non-MTU requests the same way we did for MTU ones. Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* CIFS: Respect reconnect in MTU credits calculationsPavel Shilovsky2019-03-051-6/+7
| | | | | | | | | | | | | | | | Every time after a session reconnect we don't need to account for credits obtained in previous sessions. Introduce new struct cifs_credits which contains both credits value and reconnect instance of the time those credits were taken. Modify a routine that add credits back to handle the reconnect instance by assuming zero credits if the reconnect happened after the credits were obtained and before we decided to add them back due to some errors during sending. This patch fixes the MTU credits cases. The subsequent patch will handle non-MTU ones. Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* CIFS: Do not skip SMB2 message IDs on send failuresPavel Shilovsky2019-03-041-1/+5
| | | | | | | | | | | | | | | | When we hit failures during constructing MIDs or sending PDUs through the network, we end up not using message IDs assigned to the packet. The next SMB packet will skip those message IDs and continue with the next one. This behavior may lead to a server not granting us credits until we use the skipped IDs. Fix this by reverting the current ID to the original value if any errors occur before we push the packet through the network stack. This patch fixes the generic/310 test from the xfs-tests. Cc: <stable@vger.kernel.org> # 4.19.x Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* CIFS: Fix credit calculations in compound mid callbackPavel Shilovsky2019-01-241-10/+1
| | | | | | | | | | | | | | The current code doesn't do proper accounting for credits in SMB1 case: it adds one credit per response only if we get a complete response while it needs to return it unconditionally. Fix this and also include malformed responses for SMB2+ into accounting for credits because such responses have Credit Granted field, thus nothing prevents to get a proper credit value from them. Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* CIFS: Move credit processing to mid callbacks for SMB3Pavel Shilovsky2019-01-111-17/+34
| | | | | | | | | | | | | | | Currently we account for credits in the thread initiating a request and waiting for a response. The demultiplex thread receives the response, wakes up the thread and the latter collects credits from the response buffer and add them to the server structure on the client. This approach is not accurate, because it may race with reconnect events in the demultiplex thread which resets the number of credits. Fix this by moving credit processing to new mid callbacks that collect credits granted by the server from the response in the demultiplex thread. Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* CIFS: Fix credits calculation for cancelled requestsPavel Shilovsky2019-01-111-2/+26
| | | | | | | | | | | | | | | If a request is cancelled, we can't assume that the server returns 1 credit back. Instead we need to wait for a response and process the number of credits granted by the server. Create a separate mid callback for cancelled request, parse the number of credits in a response buffer and add them to the client's credits. If the didn't get a response (no response buffer available) assume 0 credits granted. The latter most probably happens together with session reconnect, so the client's credits are adjusted anyway. Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* CIFS: Do not hide EINTR after sending network packetsPavel Shilovsky2019-01-111-1/+1
| | | | | | | | | | | | Currently we hide EINTR code returned from sock_sendmsg() and return 0 instead. This makes a caller think that we successfully completed the network operation which is not true. Fix this by properly returning EINTR to callers. Cc: <stable@vger.kernel.org> Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
* CIFS: Fix credit computation for compounded requestsPavel Shilovsky2019-01-101-18/+41
| | | | | | | | | | | | | | | In SMB3 protocol every part of the compound chain consumes credits individually, so we need to call wait_for_free_credits() for each of the PDUs in the chain. If an operation is interrupted, we must ensure we return all credits taken from the server structure back. Without this patch server can sometimes disconnect the session due to credit mismatches, especially when first operation(s) are large writes. Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com> CC: Stable <stable@vger.kernel.org>
generated by cgit v1.2.3 (git 2.25.1) at 2024-08-08 06:27:54 +0000