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2019-12-06Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfsLinus Torvalds
Pull vfs d_inode/d_flags memory ordering fixes from Al Viro: "Fallout from tree-wide audit for ->d_inode/->d_flags barriers use. Basically, the problem is that negative pinned dentries require careful treatment - unless ->d_lock is locked or parent is held at least shared, another thread can make them positive right under us. Most of the uses turned out to be safe - the main surprises as far as filesystems are concerned were - race in dget_parent() fastpath, that might end up with the caller observing the returned dentry _negative_, due to insufficient barriers. It is positive in memory, but we could end up seeing the wrong value of ->d_inode in CPU cache. Fixed. - manual checks that result of lookup_one_len_unlocked() is positive (and rejection of negatives). Again, insufficient barriers (we might end up with inconsistent observed values of ->d_inode and ->d_flags). Fixed by switching to a new primitive that does the checks itself and returns ERR_PTR(-ENOENT) instead of a negative dentry. That way we get rid of boilerplate converting negatives into ERR_PTR(-ENOENT) in the callers and have a single place to deal with the barrier-related mess - inside fs/namei.c rather than in every caller out there. The guts of pathname resolution *do* need to be careful - the race found by Ritesh is real, as well as several similar races. Fortunately, it turns out that we can take care of that with fairly local changes in there. The tree-wide audit had not been fun, and I hate the idea of repeating it. I think the right approach would be to annotate the places where we are _not_ guaranteed ->d_inode/->d_flags stability and have sparse catch regressions. But I'm still not sure what would be the least invasive way of doing that and it's clearly the next cycle fodder" * 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fs/namei.c: fix missing barriers when checking positivity fix dget_parent() fastpath race new helper: lookup_positive_unlocked() fs/namei.c: pull positivity check into follow_managed()
2019-12-02Merge tag 'docs-5.5a' of git://git.lwn.net/linuxLinus Torvalds
Pull Documentation updates from Jonathan Corbet: "Here are the main documentation changes for 5.5: - Various kerneldoc script enhancements. - More RST conversions; those are slowing down as we run out of things to convert, but we're a ways from done still. - Dan's "maintainer profile entry" work landed at last. Now we just need to get maintainers to fill in the profiles... - A reworking of the parallel build setup to work better with a variety of systems (and to not take over huge systems entirely in particular). - The MAINTAINERS file is now converted to RST during the build. Hopefully nobody ever tries to print this thing, or they will need to load a lot of paper. - A script and documentation making it easy for maintainers to add Link: tags at commit time. Also included is the removal of a bunch of spurious CR characters" * tag 'docs-5.5a' of git://git.lwn.net/linux: (91 commits) docs: remove a bunch of stray CRs docs: fix up the maintainer profile document libnvdimm, MAINTAINERS: Maintainer Entry Profile Maintainer Handbook: Maintainer Entry Profile MAINTAINERS: Reclaim the P: tag for Maintainer Entry Profile docs, parallelism: Rearrange how jobserver reservations are made docs, parallelism: Do not leak blocking mode to other readers docs, parallelism: Fix failure path and add comment Documentation: Remove bootmem_debug from kernel-parameters.txt Documentation: security: core.rst: fix warnings Documentation/process/howto/kokr: Update for 4.x -> 5.x versioning Documentation/translation: Use Korean for Korean translation title docs/memory-barriers.txt: Remove remaining references to mmiowb() docs/memory-barriers.txt/kokr: Update I/O section to be clearer about CPU vs thread docs/memory-barriers.txt/kokr: Fix style, spacing and grammar in I/O section Documentation/kokr: Kill all references to mmiowb() docs/memory-barriers.txt/kokr: Rewrite "KERNEL I/O BARRIER EFFECTS" section docs: Add initial documentation for devfreq Documentation: Document how to get links with git am docs: Add request_irq() documentation ...
2019-11-25cifs: move cifsFileInfo_put logic into a work-queueRonnie Sahlberg
This patch moves the final part of the cifsFileInfo_put() logic where we need a write lock on lock_sem to be processed in a separate thread that holds no other locks. This is to prevent deadlocks like the one below: > there are 6 processes looping to while trying to down_write > cinode->lock_sem, 5 of them from _cifsFileInfo_put, and one from > cifs_new_fileinfo > > and there are 5 other processes which are blocked, several of them > waiting on either PG_writeback or PG_locked (which are both set), all > for the same page of the file > > 2 inode_lock() (inode->i_rwsem) for the file > 1 wait_on_page_writeback() for the page > 1 down_read(inode->i_rwsem) for the inode of the directory > 1 inode_lock()(inode->i_rwsem) for the inode of the directory > 1 __lock_page > > > so processes are blocked waiting on: > page flags PG_locked and PG_writeback for one specific page > inode->i_rwsem for the directory > inode->i_rwsem for the file > cifsInodeInflock_sem > > > > here are the more gory details (let me know if I need to provide > anything more/better): > > [0 00:48:22.765] [UN] PID: 8863 TASK: ffff8c691547c5c0 CPU: 3 > COMMAND: "reopen_file" > #0 [ffff9965007e3ba8] __schedule at ffffffff9b6e6095 > #1 [ffff9965007e3c38] schedule at ffffffff9b6e64df > #2 [ffff9965007e3c48] rwsem_down_write_slowpath at ffffffff9af283d7 > #3 [ffff9965007e3cb8] legitimize_path at ffffffff9b0f975d > #4 [ffff9965007e3d08] path_openat at ffffffff9b0fe55d > #5 [ffff9965007e3dd8] do_filp_open at ffffffff9b100a33 > #6 [ffff9965007e3ee0] do_sys_open at ffffffff9b0eb2d6 > #7 [ffff9965007e3f38] do_syscall_64 at ffffffff9ae04315 > * (I think legitimize_path is bogus) > > in path_openat > } else { > const char *s = path_init(nd, flags); > while (!(error = link_path_walk(s, nd)) && > (error = do_last(nd, file, op)) > 0) { <<<< > > do_last: > if (open_flag & O_CREAT) > inode_lock(dir->d_inode); <<<< > else > so it's trying to take inode->i_rwsem for the directory > > DENTRY INODE SUPERBLK TYPE PATH > ffff8c68bb8e79c0 ffff8c691158ef20 ffff8c6915bf9000 DIR /mnt/vm1_smb/ > inode.i_rwsem is ffff8c691158efc0 > > <struct rw_semaphore 0xffff8c691158efc0>: > owner: <struct task_struct 0xffff8c6914275d00> (UN - 8856 - > reopen_file), counter: 0x0000000000000003 > waitlist: 2 > 0xffff9965007e3c90 8863 reopen_file UN 0 1:29:22.926 > RWSEM_WAITING_FOR_WRITE > 0xffff996500393e00 9802 ls UN 0 1:17:26.700 > RWSEM_WAITING_FOR_READ > > > the owner of the inode.i_rwsem of the directory is: > > [0 00:00:00.109] [UN] PID: 8856 TASK: ffff8c6914275d00 CPU: 3 > COMMAND: "reopen_file" > #0 [ffff99650065b828] __schedule at ffffffff9b6e6095 > #1 [ffff99650065b8b8] schedule at ffffffff9b6e64df > #2 [ffff99650065b8c8] schedule_timeout at ffffffff9b6e9f89 > #3 [ffff99650065b940] msleep at ffffffff9af573a9 > #4 [ffff99650065b948] _cifsFileInfo_put.cold.63 at ffffffffc0a42dd6 [cifs] > #5 [ffff99650065ba38] cifs_writepage_locked at ffffffffc0a0b8f3 [cifs] > #6 [ffff99650065bab0] cifs_launder_page at ffffffffc0a0bb72 [cifs] > #7 [ffff99650065bb30] invalidate_inode_pages2_range at ffffffff9b04d4bd > #8 [ffff99650065bcb8] cifs_invalidate_mapping at ffffffffc0a11339 [cifs] > #9 [ffff99650065bcd0] cifs_revalidate_mapping at ffffffffc0a1139a [cifs] > #10 [ffff99650065bcf0] cifs_d_revalidate at ffffffffc0a014f6 [cifs] > #11 [ffff99650065bd08] path_openat at ffffffff9b0fe7f7 > #12 [ffff99650065bdd8] do_filp_open at ffffffff9b100a33 > #13 [ffff99650065bee0] do_sys_open at ffffffff9b0eb2d6 > #14 [ffff99650065bf38] do_syscall_64 at ffffffff9ae04315 > > cifs_launder_page is for page 0xffffd1e2c07d2480 > > crash> page.index,mapping,flags 0xffffd1e2c07d2480 > index = 0x8 > mapping = 0xffff8c68f3cd0db0 > flags = 0xfffffc0008095 > > PAGE-FLAG BIT VALUE > PG_locked 0 0000001 > PG_uptodate 2 0000004 > PG_lru 4 0000010 > PG_waiters 7 0000080 > PG_writeback 15 0008000 > > > inode is ffff8c68f3cd0c40 > inode.i_rwsem is ffff8c68f3cd0ce0 > DENTRY INODE SUPERBLK TYPE PATH > ffff8c68a1f1b480 ffff8c68f3cd0c40 ffff8c6915bf9000 REG > /mnt/vm1_smb/testfile.8853 > > > this process holds the inode->i_rwsem for the parent directory, is > laundering a page attached to the inode of the file it's opening, and in > _cifsFileInfo_put is trying to down_write the cifsInodeInflock_sem > for the file itself. > > > <struct rw_semaphore 0xffff8c68f3cd0ce0>: > owner: <struct task_struct 0xffff8c6914272e80> (UN - 8854 - > reopen_file), counter: 0x0000000000000003 > waitlist: 1 > 0xffff9965005dfd80 8855 reopen_file UN 0 1:29:22.912 > RWSEM_WAITING_FOR_WRITE > > this is the inode.i_rwsem for the file > > the owner: > > [0 00:48:22.739] [UN] PID: 8854 TASK: ffff8c6914272e80 CPU: 2 > COMMAND: "reopen_file" > #0 [ffff99650054fb38] __schedule at ffffffff9b6e6095 > #1 [ffff99650054fbc8] schedule at ffffffff9b6e64df > #2 [ffff99650054fbd8] io_schedule at ffffffff9b6e68e2 > #3 [ffff99650054fbe8] __lock_page at ffffffff9b03c56f > #4 [ffff99650054fc80] pagecache_get_page at ffffffff9b03dcdf > #5 [ffff99650054fcc0] grab_cache_page_write_begin at ffffffff9b03ef4c > #6 [ffff99650054fcd0] cifs_write_begin at ffffffffc0a064ec [cifs] > #7 [ffff99650054fd30] generic_perform_write at ffffffff9b03bba4 > #8 [ffff99650054fda8] __generic_file_write_iter at ffffffff9b04060a > #9 [ffff99650054fdf0] cifs_strict_writev.cold.70 at ffffffffc0a4469b [cifs] > #10 [ffff99650054fe48] new_sync_write at ffffffff9b0ec1dd > #11 [ffff99650054fed0] vfs_write at ffffffff9b0eed35 > #12 [ffff99650054ff00] ksys_write at ffffffff9b0eefd9 > #13 [ffff99650054ff38] do_syscall_64 at ffffffff9ae04315 > > the process holds the inode->i_rwsem for the file to which it's writing, > and is trying to __lock_page for the same page as in the other processes > > > the other tasks: > [0 00:00:00.028] [UN] PID: 8859 TASK: ffff8c6915479740 CPU: 2 > COMMAND: "reopen_file" > #0 [ffff9965007b39d8] __schedule at ffffffff9b6e6095 > #1 [ffff9965007b3a68] schedule at ffffffff9b6e64df > #2 [ffff9965007b3a78] schedule_timeout at ffffffff9b6e9f89 > #3 [ffff9965007b3af0] msleep at ffffffff9af573a9 > #4 [ffff9965007b3af8] cifs_new_fileinfo.cold.61 at ffffffffc0a42a07 [cifs] > #5 [ffff9965007b3b78] cifs_open at ffffffffc0a0709d [cifs] > #6 [ffff9965007b3cd8] do_dentry_open at ffffffff9b0e9b7a > #7 [ffff9965007b3d08] path_openat at ffffffff9b0fe34f > #8 [ffff9965007b3dd8] do_filp_open at ffffffff9b100a33 > #9 [ffff9965007b3ee0] do_sys_open at ffffffff9b0eb2d6 > #10 [ffff9965007b3f38] do_syscall_64 at ffffffff9ae04315 > > this is opening the file, and is trying to down_write cinode->lock_sem > > > [0 00:00:00.041] [UN] PID: 8860 TASK: ffff8c691547ae80 CPU: 2 > COMMAND: "reopen_file" > [0 00:00:00.057] [UN] PID: 8861 TASK: ffff8c6915478000 CPU: 3 > COMMAND: "reopen_file" > [0 00:00:00.059] [UN] PID: 8858 TASK: ffff8c6914271740 CPU: 2 > COMMAND: "reopen_file" > [0 00:00:00.109] [UN] PID: 8862 TASK: ffff8c691547dd00 CPU: 6 > COMMAND: "reopen_file" > #0 [ffff9965007c3c78] __schedule at ffffffff9b6e6095 > #1 [ffff9965007c3d08] schedule at ffffffff9b6e64df > #2 [ffff9965007c3d18] schedule_timeout at ffffffff9b6e9f89 > #3 [ffff9965007c3d90] msleep at ffffffff9af573a9 > #4 [ffff9965007c3d98] _cifsFileInfo_put.cold.63 at ffffffffc0a42dd6 [cifs] > #5 [ffff9965007c3e88] cifs_close at ffffffffc0a07aaf [cifs] > #6 [ffff9965007c3ea0] __fput at ffffffff9b0efa6e > #7 [ffff9965007c3ee8] task_work_run at ffffffff9aef1614 > #8 [ffff9965007c3f20] exit_to_usermode_loop at ffffffff9ae03d6f > #9 [ffff9965007c3f38] do_syscall_64 at ffffffff9ae0444c > > closing the file, and trying to down_write cifsi->lock_sem > > > [0 00:48:22.839] [UN] PID: 8857 TASK: ffff8c6914270000 CPU: 7 > COMMAND: "reopen_file" > #0 [ffff9965006a7cc8] __schedule at ffffffff9b6e6095 > #1 [ffff9965006a7d58] schedule at ffffffff9b6e64df > #2 [ffff9965006a7d68] io_schedule at ffffffff9b6e68e2 > #3 [ffff9965006a7d78] wait_on_page_bit at ffffffff9b03cac6 > #4 [ffff9965006a7e10] __filemap_fdatawait_range at ffffffff9b03b028 > #5 [ffff9965006a7ed8] filemap_write_and_wait at ffffffff9b040165 > #6 [ffff9965006a7ef0] cifs_flush at ffffffffc0a0c2fa [cifs] > #7 [ffff9965006a7f10] filp_close at ffffffff9b0e93f1 > #8 [ffff9965006a7f30] __x64_sys_close at ffffffff9b0e9a0e > #9 [ffff9965006a7f38] do_syscall_64 at ffffffff9ae04315 > > in __filemap_fdatawait_range > wait_on_page_writeback(page); > for the same page of the file > > > > [0 00:48:22.718] [UN] PID: 8855 TASK: ffff8c69142745c0 CPU: 7 > COMMAND: "reopen_file" > #0 [ffff9965005dfc98] __schedule at ffffffff9b6e6095 > #1 [ffff9965005dfd28] schedule at ffffffff9b6e64df > #2 [ffff9965005dfd38] rwsem_down_write_slowpath at ffffffff9af283d7 > #3 [ffff9965005dfdf0] cifs_strict_writev at ffffffffc0a0c40a [cifs] > #4 [ffff9965005dfe48] new_sync_write at ffffffff9b0ec1dd > #5 [ffff9965005dfed0] vfs_write at ffffffff9b0eed35 > #6 [ffff9965005dff00] ksys_write at ffffffff9b0eefd9 > #7 [ffff9965005dff38] do_syscall_64 at ffffffff9ae04315 > > inode_lock(inode); > > > and one 'ls' later on, to see whether the rest of the mount is available > (the test file is in the root, so we get blocked up on the directory > ->i_rwsem), so the entire mount is unavailable > > [0 00:36:26.473] [UN] PID: 9802 TASK: ffff8c691436ae80 CPU: 4 > COMMAND: "ls" > #0 [ffff996500393d28] __schedule at ffffffff9b6e6095 > #1 [ffff996500393db8] schedule at ffffffff9b6e64df > #2 [ffff996500393dc8] rwsem_down_read_slowpath at ffffffff9b6e9421 > #3 [ffff996500393e78] down_read_killable at ffffffff9b6e95e2 > #4 [ffff996500393e88] iterate_dir at ffffffff9b103c56 > #5 [ffff996500393ec8] ksys_getdents64 at ffffffff9b104b0c > #6 [ffff996500393f30] __x64_sys_getdents64 at ffffffff9b104bb6 > #7 [ffff996500393f38] do_syscall_64 at ffffffff9ae04315 > > in iterate_dir: > if (shared) > res = down_read_killable(&inode->i_rwsem); <<<< > else > res = down_write_killable(&inode->i_rwsem); > Reported-by: Frank Sorenson <sorenson@redhat.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-11-25cifs: add multichannel mount options and data structsAurelien Aptel
adds: - [no]multichannel to enable/disable multichannel - max_channels=N to control how many channels to create these options are then stored in the volume struct. - store channels and max_channels in cifs_ses Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-11-25cifs: don't use 'pre:' for MODULE_SOFTDEPRonnie Sahlberg
It can cause to fail with modprobe: FATAL: Module <module> is builtin. RHBZ: 1767094 Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-11-25cifs: add support for flockSteve French
The flock system call locks the whole file rather than a byte range and so is currently emulated by various other file systems by simply sending a byte range lock for the whole file. Add flock handling for cifs.ko in similar way. xfstest generic/504 passes with this as well Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2019-11-15new helper: lookup_positive_unlocked()Al Viro
Most of the callers of lookup_one_len_unlocked() treat negatives are ERR_PTR(-ENOENT). Provide a helper that would do just that. Note that a pinned positive dentry remains positive - it's ->d_inode is stable, etc.; a pinned _negative_ dentry can become positive at any point as long as you are not holding its parent at least shared. So using lookup_one_len_unlocked() needs to be careful; lookup_positive_unlocked() is safer and that's what the callers end up open-coding anyway. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-10-29Merge tag 'v5.4-rc4' into docs-nextJonathan Corbet
I need to pick up the independent changes made to Documentation/core-api/memory-allocation.rst to be able to merge further work without creating a total mess.
2019-10-20cifs: clarify comment about timestamp granularity for old serversSteve French
It could be confusing why we set granularity to 1 seconds rather than 2 seconds (1 second is the max the VFS allows) for these mounts to very old servers ... Signed-off-by: Steve French <stfrench@microsoft.com>
2019-10-10docs: fix some broken referencesMauro Carvalho Chehab
There are a number of documentation files that got moved or renamed. update their references. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Acked-by: Shannon Nelson <snelson@pensando.io> Acked-by: Guenter Roeck <linux@roeck-us.net> Acked-by: Rob Herring <robh@kernel.org> Acked-by: Paul Walmsley <paul.walmsley@sifive.com> # RISC-V Acked-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-10-09smb3: Fix regression in time handlingSteve French
Fixes: cb7a69e60590 ("cifs: Initialize filesystem timestamp ranges") Only very old servers (e.g. OS/2 and DOS) did not support DCE TIME (100 nanosecond granularity). Fix the checks used to set minimum and maximum times. Fixes xfstest generic/258 (on 5.4-rc1 and later) CC: Deepa Dinamani <deepa.kernel@gmail.com> Acked-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2019-09-19Merge tag '5.4-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6Linus Torvalds
Pull cifs updates from Steve French: "Various cifs/smb3 fixes (including for share deleted cases) and features including improved encrypted read performance, and various debugging improvements. Note that since I am at a test event this week with the Samba team, and at the annual Storage Developer Conference/SMB3 Plugfest test event next week a higher than usual number of fixes is expected later next week as other features in progress get additional testing and review during these two events" * tag '5.4-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6: (38 commits) cifs: update internal module version number cifs: modefromsid: write mode ACE first cifs: cifsroot: add more err checking smb3: add missing worker function for SMB3 change notify cifs: Add support for root file systems cifs: modefromsid: make room for 4 ACE smb3: fix potential null dereference in decrypt offload smb3: fix unmount hang in open_shroot smb3: allow disabling requesting leases smb3: improve handling of share deleted (and share recreated) smb3: display max smb3 requests in flight at any one time smb3: only offload decryption of read responses if multiple requests cifs: add a helper to find an existing readable handle to a file smb3: enable offload of decryption of large reads via mount option smb3: allow parallelizing decryption of reads cifs: add a debug macro that prints \\server\share for errors smb3: fix signing verification of large reads smb3: allow skipping signature verification for perf sensitive configurations smb3: add dynamic tracepoints for flush and close smb3: log warning if CSC policy conflicts with cache mount option ...
2019-09-19Merge tag 'y2038-vfs' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground Pull y2038 vfs updates from Arnd Bergmann: "Add inode timestamp clamping. This series from Deepa Dinamani adds a per-superblock minimum/maximum timestamp limit for a file system, and clamps timestamps as they are written, to avoid random behavior from integer overflow as well as having different time stamps on disk vs in memory. At mount time, a warning is now printed for any file system that can represent current timestamps but not future timestamps more than 30 years into the future, similar to the arbitrary 30 year limit that was added to settimeofday(). This was picked as a compromise to warn users to migrate to other file systems (e.g. ext4 instead of ext3) when they need the file system to survive beyond 2038 (or similar limits in other file systems), but not get in the way of normal usage" * tag 'y2038-vfs' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground: ext4: Reduce ext4 timestamp warnings isofs: Initialize filesystem timestamp ranges pstore: fs superblock limits fs: omfs: Initialize filesystem timestamp ranges fs: hpfs: Initialize filesystem timestamp ranges fs: ceph: Initialize filesystem timestamp ranges fs: sysv: Initialize filesystem timestamp ranges fs: affs: Initialize filesystem timestamp ranges fs: fat: Initialize filesystem timestamp ranges fs: cifs: Initialize filesystem timestamp ranges fs: nfs: Initialize filesystem timestamp ranges ext4: Initialize timestamps limits 9p: Fill min and max timestamps in sb fs: Fill in max and min timestamps in superblock utimes: Clamp the timestamps before update mount: Add mount warning for impending timestamp expiry timestamp_truncate: Replace users of timespec64_trunc vfs: Add timestamp_truncate() api vfs: Add file timestamp range support
2019-09-16smb3: allow disabling requesting leasesSteve French
In some cases to work around server bugs or performance problems it can be helpful to be able to disable requesting SMB2.1/SMB3 leases on a particular mount (not to all servers and all shares we are mounted to). Add new mount parm "nolease" which turns off requesting leases on directory or file opens. Currently the only way to disable leases is globally through a module load parameter. This is more granular. Suggested-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com> CC: Stable <stable@vger.kernel.org>
2019-09-16smb3: only offload decryption of read responses if multiple requestsSteve French
No point in offloading read decryption if no other requests on the wire Signed-off-by: Steve French <stfrench@microsoft.com> Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
2019-09-16smb3: enable offload of decryption of large reads via mount optionSteve French
Disable offload of the decryption of encrypted read responses by default (equivalent to setting this new mount option "esize=0"). Allow setting the minimum encrypted read response size that we will choose to offload to a worker thread - it is now configurable via on a new mount option "esize=" Depending on which encryption mechanism (GCM vs. CCM) and the number of reads that will be issued in parallel and the performance of the network and CPU on the client, it may make sense to enable this since it can provide substantial benefit when multiple large reads are in flight at the same time. Signed-off-by: Steve French <stfrench@microsoft.com> Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
2019-09-16smb3: allow parallelizing decryption of readsSteve French
decrypting large reads on encrypted shares can be slow (e.g. adding multiple milliseconds per-read on non-GCM capable servers or when mounting with dialects prior to SMB3.1.1) - allow parallelizing of read decryption by launching worker threads. Testing to Samba on localhost showed 25% improvement. Testing to remote server showed very large improvement when doing more than one 'cp' command was called at one time. Signed-off-by: Steve French <stfrench@microsoft.com> Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
2019-09-16smb3: add mount option to allow RW caching of share accessed by only 1 clientSteve French
If a share is known to be only to be accessed by one client, we can aggressively cache writes not just reads to it. Add "cache=" option (cache=singleclient) for mounting read write shares (that will not be read or written to from other clients while we have it mounted) in order to improve performance. Signed-off-by: Steve French <stfrench@microsoft.com>
2019-09-16smb3: add mount option to allow forced caching of read only shareSteve French
If a share is immutable (at least for the period that it will be mounted) it would be helpful to not have to revalidate dentries repeatedly that we know can not be changed remotely. Add "cache=" option (cache=ro) for mounting read only shares in order to improve performance in cases in which we know that the share will not be changing while it is in use. Signed-off-by: Steve French <stfrench@microsoft.com>
2019-08-30fs: cifs: Initialize filesystem timestamp rangesDeepa Dinamani
Fill in the appropriate limits to avoid inconsistencies in the vfs cached inode times when timestamps are outside the permitted range. Also fixed cnvrtDosUnixTm calculations to avoid int overflow while computing maximum date. References: http://cifs.com/ https://docs.microsoft.com/en-us/openspecs/windows_protocols/ms-cifs/d416ff7c-c536-406e-a951-4f04b2fd1d2b Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Acked-by: Jeff Layton <jlayton@kernel.org> Cc: sfrench@samba.org Cc: linux-cifs@vger.kernel.org
2019-08-22fs: cifs: move from the crypto cipher API to the new DES library interfaceArd Biesheuvel
Some legacy code in the CIFS driver uses single DES to calculate some password hash, and uses the crypto cipher API to do so. Given that there is no point in invoking an accelerated cipher for doing 56-bit symmetric encryption on a single 8-byte block of input, the flexibility of the crypto cipher API does not add much value here, and so we're much better off using a library call into the generic C implementation. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-07-18cifs: copy_file_range needs to strip setuid bits and update timestampsAmir Goldstein
cifs has both source and destination inodes locked throughout the copy. Like ->write_iter(), we update mtime and strip setuid bits of destination file before copy and like ->read_iter(), we update atime of source file after copy. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-07-18Merge tag '4.3-rc-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6Linus Torvalds
Pull cifs updates from Steve French: "Fixes (three for stable) and improvements including much faster encryption (SMB3.1.1 GCM)" * tag '4.3-rc-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6: (27 commits) smb3: smbdirect no longer experimental cifs: fix crash in smb2_compound_op()/smb2_set_next_command() cifs: fix crash in cifs_dfs_do_automount cifs: fix parsing of symbolic link error response cifs: refactor and clean up arguments in the reparse point parsing SMB3: query inode number on open via create context smb3: Send netname context during negotiate protocol smb3: do not send compression info by default smb3: add new mount option to retrieve mode from special ACE smb3: Allow query of symlinks stored as reparse points cifs: Fix a race condition with cifs_echo_request cifs: always add credits back for unsolicited PDUs fs: cifs: cifsssmb: Change return type of convert_ace_to_cifs_ace add some missing definitions cifs: fix typo in debug message with struct field ia_valid smb3: minor cleanup of compound_send_recv CIFS: Fix module dependency cifs: simplify code by removing CONFIG_CIFS_ACL ifdef cifs: Fix check for matching with existing mount cifs: Properly handle auto disabling of serverino option ...
2019-07-10Merge tag 'copy-file-range-fixes-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/fs/xfs/xfs-linux Pull copy_file_range updates from Darrick Wong: "This fixes numerous parameter checking problems and inconsistent behaviors in the new(ish) copy_file_range system call. Now the system call will actually check its range parameters correctly; refuse to copy into files for which the caller does not have sufficient privileges; update mtime and strip setuid like file writes are supposed to do; and allows copying up to the EOF of the source file instead of failing the call like we used to. Summary: - Create a generic copy_file_range handler and make individual filesystems responsible for calling it (i.e. no more assuming that do_splice_direct will work or is appropriate) - Refactor copy_file_range and remap_range parameter checking where they are the same - Install missing copy_file_range parameter checking(!) - Remove suid/sgid and update mtime like any other file write - Change the behavior so that a copy range crossing the source file's eof will result in a short copy to the source file's eof instead of EINVAL - Permit filesystems to decide if they want to handle cross-superblock copy_file_range in their local handlers" * tag 'copy-file-range-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: fuse: copy_file_range needs to strip setuid bits and update timestamps vfs: allow copy_file_range to copy across devices xfs: use file_modified() helper vfs: introduce file_modified() helper vfs: add missing checks to copy_file_range vfs: remove redundant checks from generic_remap_checks() vfs: introduce generic_file_rw_checks() vfs: no fallback for ->copy_file_range vfs: introduce generic_copy_file_range()
2019-07-08Merge branch 'linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 Pull crypto updates from Herbert Xu: "Here is the crypto update for 5.3: API: - Test shash interface directly in testmgr - cra_driver_name is now mandatory Algorithms: - Replace arc4 crypto_cipher with library helper - Implement 5 way interleave for ECB, CBC and CTR on arm64 - Add xxhash - Add continuous self-test on noise source to drbg - Update jitter RNG Drivers: - Add support for SHA204A random number generator - Add support for 7211 in iproc-rng200 - Fix fuzz test failures in inside-secure - Fix fuzz test failures in talitos - Fix fuzz test failures in qat" * 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (143 commits) crypto: stm32/hash - remove interruptible condition for dma crypto: stm32/hash - Fix hmac issue more than 256 bytes crypto: stm32/crc32 - rename driver file crypto: amcc - remove memset after dma_alloc_coherent crypto: ccp - Switch to SPDX license identifiers crypto: ccp - Validate the the error value used to index error messages crypto: doc - Fix formatting of new crypto engine content crypto: doc - Add parameter documentation crypto: arm64/aes-ce - implement 5 way interleave for ECB, CBC and CTR crypto: arm64/aes-ce - add 5 way interleave routines crypto: talitos - drop icv_ool crypto: talitos - fix hash on SEC1. crypto: talitos - move struct talitos_edesc into talitos.h lib/scatterlist: Fix mapping iterator when sg->offset is greater than PAGE_SIZE crypto/NX: Set receive window credits to max number of CRBs in RxFIFO crypto: asymmetric_keys - select CRYPTO_HASH where needed crypto: serpent - mark __serpent_setkey_sbox noinline crypto: testmgr - dynamically allocate crypto_shash crypto: testmgr - dynamically allocate testvec_config crypto: talitos - eliminate unneeded 'done' functions at build time ...
2019-07-07smb3: add new mount option to retrieve mode from special ACESteve French
There is a special ACE used by some servers to allow the mode bits to be stored. This can be especially helpful in scenarios in which the client is trusted, and access checking on the client vs the POSIX mode bits is sufficient. Add mount option to allow enabling this behavior. Follow on patch will add support for chmod and queryinfo (stat) by retrieving the POSIX mode bits from the special ACE, SID: S-1-5-88-3 See e.g. https://docs.microsoft.com/en-us/previous-versions/windows/it-pro/windows-server-2008-R2-and-2008/hh509017(v=ws.10) Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2019-07-07cifs: simplify code by removing CONFIG_CIFS_ACL ifdefSteve French
SMB3 ACL support is needed for many use cases now and should not be ifdeffed out, even for SMB1 (CIFS). Remove the CONFIG_CIFS_ACL ifdef so ACL support is always built into cifs.ko Signed-off-by: Steve French <stfrench@microsoft.com>
2019-07-07smb3: if max_credits is specified then display it in /proc/mountsSteve French
If "max_credits" is overridden from its default by specifying it on the smb3 mount then display it in /proc/mounts Signed-off-by: Steve French <stfrench@microsoft.com>
2019-07-07cifs: add missing GCM module dependencyAurelien Aptel
Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-06-20fs: cifs: switch to RC4 library interfaceArd Biesheuvel
The CIFS code uses the sync skcipher API to invoke the ecb(arc4) skcipher, of which only a single generic C code implementation exists. This means that going through all the trouble of using scatterlists etc buys us very little, and we're better off just invoking the arc4 library directly. This also reverts commit 5f4b55699aaf ("CIFS: Fix BUG() in calc_seckey()"), since it is no longer necessary to allocate sec_key on the heap. Cc: linux-cifs@vger.kernel.org Cc: Steve French <sfrench@samba.org> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Steve French <stfrench@microsoft.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-06-13cifs: add spinlock for the openFileList to cifsInodeInfoRonnie Sahlberg
We can not depend on the tcon->open_file_lock here since in multiuser mode we may have the same file/inode open via multiple different tcons. The current code is race prone and will crash if one user deletes a file at the same time a different user opens/create the file. To avoid this we need to have a spinlock attached to the inode and not the tcon. RHBZ: 1580165 CC: Stable <stable@vger.kernel.org> Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2019-06-09vfs: allow copy_file_range to copy across devicesAmir Goldstein
We want to enable cross-filesystem copy_file_range functionality where possible, so push the "same superblock only" checks down to the individual filesystem callouts so they can make their own decisions about cross-superblock copy offload and fallack to generic_copy_file_range() for cross-superblock copy. [Amir] We do not call ->remap_file_range() in case the files are not on the same sb and do not call ->copy_file_range() in case the files do not belong to the same filesystem driver. This changes behavior of the copy_file_range(2) syscall, which will now allow cross filesystem in-kernel copy. CIFS already supports cross-superblock copy, between two shares to the same server. This functionality will now be available via the copy_file_range(2) syscall. Cc: Steve French <stfrench@microsoft.com> Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-06-09vfs: no fallback for ->copy_file_rangeDave Chinner
Now that we have generic_copy_file_range(), remove it as a fallback case when offloads fail. This puts the responsibility for executing fallbacks on the filesystems that implement ->copy_file_range and allows us to add operational validity checks to generic_copy_file_range(). Rework vfs_copy_file_range() to call a new do_copy_file_range() helper to execute the copying callout, and move calls to generic_file_copy_range() into filesystem methods where they currently return failures. [Amir] overlayfs is not responsible of executing the fallback. It is the responsibility of the underlying filesystem. Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-05-15cifs: add support for SEEK_DATA and SEEK_HOLERonnie Sahlberg
Add llseek op for SEEK_DATA and SEEK_HOLE. Improves xfstests/285,286,436,445,448 and 490 Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-05-15Fixed https://bugzilla.kernel.org/show_bug.cgi?id=202935 allow write on the ↵Kovtunenko Oleksandr
same file Copychunk allows source and target to be on the same file. For details on restrictions see MS-SMB2 3.3.5.15.6 Signed-off-by: Kovtunenko Oleksandr <alexander198961@gmail.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-05-07cifs: add fiemap supportRonnie Sahlberg
Useful for improved copy performance as well as for applications which query allocated ranges of sparse files. Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-05-07CIFS: Show locallease in /proc/mounts for cifs shares mounted with ↵Kenneth D'souza
locallease feature. Missing parameter that should be displayed in the mount list Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Kenneth D'souza <kdsouza@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-05-01cifs: switch to ->free_inode()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-04-01SMB3: Allow persistent handle timeout to be configurable on mountSteve French
Reconnecting after server or network failure can be improved (to maintain availability and protect data integrity) by allowing the client to choose the default persistent (or resilient) handle timeout in some use cases. Today we default to 0 which lets the server pick the default timeout (usually 120 seconds) but this can be problematic for some workloads. Add the new mount parameter to cifs.ko for SMB3 mounts "handletimeout" which enables the user to override the default handle timeout for persistent (mount option "persistenthandles") or resilient handles (mount option "resilienthandles"). Maximum allowed is 16 minutes (960000 ms). Units for the timeout are expressed in milliseconds. See section 2.2.14.2.12 and 2.2.31.3 of the MS-SMB2 protocol specification for more information. Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> CC: Stable <stable@vger.kernel.org>
2019-03-22cifs: fix that return -EINVAL when do dedupe operationXiaoli Feng
dedupe_file_range operations is combiled into remap_file_range. But it's always skipped for dedupe operations in function cifs_remap_file_range. Example to test: Before this patch: # dd if=/dev/zero of=cifs/file bs=1M count=1 # xfs_io -c "dedupe cifs/file 4k 64k 4k" cifs/file XFS_IOC_FILE_EXTENT_SAME: Invalid argument After this patch: # dd if=/dev/zero of=cifs/file bs=1M count=1 # xfs_io -c "dedupe cifs/file 4k 64k 4k" cifs/file XFS_IOC_FILE_EXTENT_SAME: Operation not supported Influence for xfstests: generic/091 generic/112 generic/127 generic/263 These tests report this error "do_copy_range:: Invalid argument" instead of "FIDEDUPERANGE: Invalid argument". Because there are still two bugs cause these test failed. https://bugzilla.kernel.org/show_bug.cgi?id=202935 https://bugzilla.kernel.org/show_bug.cgi?id=202785 Signed-off-by: Xiaoli Feng <fengxiaoli0714@gmail.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-03-05smb3: for kerberos mounts display the credential uid usedSteve French
For kerberos mounts, the cruid is helpful to display in /proc/mounts in order to tell which uid's krb5 cache we got the ticket for and to tell in the multiuser krb5 case which local users (uids) we have Kerberos authentic sessions for. Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2019-03-04smb3: make default i/o size for smb3 mounts largerSteve French
We negotiate rsize mounts (and it can be overridden by user) to typically 4MB, so using larger default I/O sizes from userspace (changing to 1MB default i/o size returned by stat) the performance is much better (and not just for long latency network connections) in most use cases for SMB3 than the default I/O size (which ends up being 128K for cp and can be even smaller for cp). This can be 4x slower or worse depending on network latency. By changing inode->blocksize from 32K (which was perhaps ok for very old SMB1/CIFS) to a larger value, 1MB (but still less than max size negotiated with the server which is 4MB, in order to minimize risk) it significantly increases performance for the noncached case, and slightly increases it for the cached case. This can be changed by the user on mount (specifying bsize= values from 16K to 16MB) to tune better for performance for applications that depend on blocksize. Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> CC: Stable <stable@vger.kernel.org>
2018-12-28cifs: Make use of DFS cache to get new DFS referralsPaulo Alcantara
This patch will make use of DFS cache routines where appropriate and do not always request a new referral from server. Signed-off-by: Paulo Alcantara <palcantara@suse.de> Reviewed-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2018-11-02cifs: don't dereference smb_file_target before null checkColin Ian King
There is a null check on dst_file->private data which suggests it can be potentially null. However, before this check, pointer smb_file_target is derived from dst_file->private and dereferenced in the call to tlink_tcon, hence there is a potential null pointer deference. Fix this by assigning smb_file_target and target_tcon after the null pointer sanity checks. Detected by CoverityScan, CID#1475302 ("Dereference before null check") Fixes: 04b38d601239 ("vfs: pull btrfs clone API to vfs layer") Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2018-11-02CIFS: Add direct I/O functions to file_operationsLong Li
With direct read/write functions implemented, add them to file_operations. Dircet I/O is used under two conditions: 1. When mounting with "cache=none", CIFS uses direct I/O for all user file data transfer. 2. When opening a file with O_DIRECT, CIFS uses direct I/O for all data transfer on this file. Signed-off-by: Long Li <longli@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2018-11-02Merge tag 'xfs-4.20-merge-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds
Pull vfs dedup fixes from Dave Chinner: "This reworks the vfs data cloning infrastructure. We discovered many issues with these interfaces late in the 4.19 cycle - the worst of them (data corruption, setuid stripping) were fixed for XFS in 4.19-rc8, but a larger rework of the infrastructure fixing all the problems was needed. That rework is the contents of this pull request. Rework the vfs_clone_file_range and vfs_dedupe_file_range infrastructure to use a common .remap_file_range method and supply generic bounds and sanity checking functions that are shared with the data write path. The current VFS infrastructure has problems with rlimit, LFS file sizes, file time stamps, maximum filesystem file sizes, stripping setuid bits, etc and so they are addressed in these commits. We also introduce the ability for the ->remap_file_range methods to return short clones so that clones for vfs_copy_file_range() don't get rejected if the entire range can't be cloned. It also allows filesystems to sliently skip deduplication of partial EOF blocks if they are not capable of doing so without requiring errors to be thrown to userspace. Existing filesystems are converted to user the new remap_file_range method, and both XFS and ocfs2 are modified to make use of the new generic checking infrastructure" * tag 'xfs-4.20-merge-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (28 commits) xfs: remove [cm]time update from reflink calls xfs: remove xfs_reflink_remap_range xfs: remove redundant remap partial EOF block checks xfs: support returning partial reflink results xfs: clean up xfs_reflink_remap_blocks call site xfs: fix pagecache truncation prior to reflink ocfs2: remove ocfs2_reflink_remap_range ocfs2: support partial clone range and dedupe range ocfs2: fix pagecache truncation prior to reflink ocfs2: truncate page cache for clone destination file before remapping vfs: clean up generic_remap_file_range_prep return value vfs: hide file range comparison function vfs: enable remap callers that can handle short operations vfs: plumb remap flags through the vfs dedupe functions vfs: plumb remap flags through the vfs clone functions vfs: make remap_file_range functions take and return bytes completed vfs: remap helper should update destination inode metadata vfs: pass remap flags to generic_remap_checks vfs: pass remap flags to generic_remap_file_range_prep vfs: combine the clone and dedupe into a single remap_file_range ...
2018-10-30vfs: make remap_file_range functions take and return bytes completedDarrick J. Wong
Change the remap_file_range functions to take a number of bytes to operate upon and return the number of bytes they operated on. This is a requirement for allowing fs implementations to return short clone/dedupe results to the user, which will enable us to obey resource limits in a graceful manner. A subsequent patch will enable copy_file_range to signal to the ->clone_file_range implementation that it can handle a short length, which will be returned in the function's return value. For now the short return is not implemented anywhere so the behavior won't change -- either copy_file_range manages to clone the entire range or it tries an alternative. Neither clone ioctl can take advantage of this, alas. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2018-10-30vfs: combine the clone and dedupe into a single remap_file_rangeDarrick J. Wong
Combine the clone_file_range and dedupe_file_range operations into a single remap_file_range file operation dispatch since they're fundamentally the same operation. The differences between the two can be made in the prep functions. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Chinner <david@fromorbit.com>
2018-10-23cifs: minor clarification in commentsSteve French
Clarify meaning (in comments) meaning of various options for debug messages in cifs.ko. Also fixed trivial formatting/style issue with previous patch. Signed-off-by: Steve French <stfrench@microsoft.com>
2018-10-23CIFS: Print message when attempting a mountRodrigo Freire
Currently, no messages are printed when mounting a CIFS filesystem and no debug configuration is enabled. However, a CIFS mount information is valuable when troubleshooting and/or forensic analyzing a system and finding out if was a CIFS endpoint mount attempted. Other filesystems such as XFS, EXT* does issue a printk() when mounting their filesystems. A terse log message is printed only if cifsFYI is not enabled. Otherwise, the default full debug message is printed. In order to not clutter and classify correctly the event messages, these are logged as KERN_INFO level. Sample mount operations: [root@corinthians ~]# mount -o user=administrator //172.25.250.18/c$ /mnt (non-existent system) [root@corinthians ~]# mount -o user=administrator //172.25.250.19/c$ /mnt (Valid system) Kernel message log for the mount operations: [ 450.464543] CIFS: Attempting to mount //172.25.250.18/c$ [ 456.478186] CIFS VFS: Error connecting to socket. Aborting operation. [ 456.478381] CIFS VFS: cifs_mount failed w/return code = -113 [ 467.688866] CIFS: Attempting to mount //172.25.250.19/c$ Signed-off-by: Rodrigo Freire <rfreire@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com>