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path: root/fs/cifs/misc.c
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2019-08-27cifs: replace various strncpy with strscpy and similarRonnie Sahlberg
Using strscpy is cleaner, and avoids some problems with handling maximum length strings. Linus noticed the original problem and Aurelien pointed out some additional problems. Fortunately most of this is SMB1 code (and in particular the ASCII string handling older, which is less common). Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Reviewed-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-07-07cifs: Properly handle auto disabling of serverino optionPaulo Alcantara (SUSE)
Fix mount options comparison when serverino option is turned off later in cifs_autodisable_serverino() and thus avoiding mismatch of new cifs mounts. Cc: stable@vger.kernel.org Signed-off-by: Paulo Alcantara (SUSE) <paulo@paulo.ac> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Pavel Shilovsky <pshilove@microsoft.com>
2019-05-06Merge branch 'linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 Pull crypto update from Herbert Xu: "API: - Add support for AEAD in simd - Add fuzz testing to testmgr - Add panic_on_fail module parameter to testmgr - Use per-CPU struct instead multiple variables in scompress - Change verify API for akcipher Algorithms: - Convert x86 AEAD algorithms over to simd - Forbid 2-key 3DES in FIPS mode - Add EC-RDSA (GOST 34.10) algorithm Drivers: - Set output IV with ctr-aes in crypto4xx - Set output IV in rockchip - Fix potential length overflow with hashing in sun4i-ss - Fix computation error with ctr in vmx - Add SM4 protected keys support in ccree - Remove long-broken mxc-scc driver - Add rfc4106(gcm(aes)) cipher support in cavium/nitrox" * 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (179 commits) crypto: ccree - use a proper le32 type for le32 val crypto: ccree - remove set but not used variable 'du_size' crypto: ccree - Make cc_sec_disable static crypto: ccree - fix spelling mistake "protedcted" -> "protected" crypto: caam/qi2 - generate hash keys in-place crypto: caam/qi2 - fix DMA mapping of stack memory crypto: caam/qi2 - fix zero-length buffer DMA mapping crypto: stm32/cryp - update to return iv_out crypto: stm32/cryp - remove request mutex protection crypto: stm32/cryp - add weak key check for DES crypto: atmel - remove set but not used variable 'alg_name' crypto: picoxcell - Use dev_get_drvdata() crypto: crypto4xx - get rid of redundant using_sd variable crypto: crypto4xx - use sync skcipher for fallback crypto: crypto4xx - fix cfb and ofb "overran dst buffer" issues crypto: crypto4xx - fix ctr-aes missing output IV crypto: ecrdsa - select ASN1 and OID_REGISTRY for EC-RDSA crypto: ux500 - use ccflags-y instead of CFLAGS_<basename>.o crypto: ccree - handle tee fips error during power management resume crypto: ccree - add function to handle cryptocell tee fips error ...
2019-04-25crypto: shash - remove shash_desc::flagsEric Biggers
The flags field in 'struct shash_desc' never actually does anything. The only ostensibly supported flag is CRYPTO_TFM_REQ_MAY_SLEEP. However, no shash algorithm ever sleeps, making this flag a no-op. With this being the case, inevitably some users who can't sleep wrongly pass MAY_SLEEP. These would all need to be fixed if any shash algorithm actually started sleeping. For example, the shash_ahash_*() functions, which wrap a shash algorithm with the ahash API, pass through MAY_SLEEP from the ahash API to the shash API. However, the shash functions are called under kmap_atomic(), so actually they're assumed to never sleep. Even if it turns out that some users do need preemption points while hashing large buffers, we could easily provide a helper function crypto_shash_update_large() which divides the data into smaller chunks and calls crypto_shash_update() and cond_resched() for each chunk. It's not necessary to have a flag in 'struct shash_desc', nor is it necessary to make individual shash algorithms aware of this at all. Therefore, remove shash_desc::flags, and document that the crypto_shash_*() functions can be called from any context. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-04-24cifs: fix page reference leak with readv/writevJérôme Glisse
CIFS can leak pages reference gotten through GUP (get_user_pages*() through iov_iter_get_pages()). This happen if cifs_send_async_read() or cifs_write_from_iter() calls fail from within __cifs_readv() and __cifs_writev() respectively. This patch move page unreference to cifs_aio_ctx_release() which will happens on all code paths this is all simpler to follow for correctness. Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Cc: Steve French <sfrench@samba.org> Cc: linux-cifs@vger.kernel.org Cc: samba-technical@lists.samba.org Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: linux-fsdevel@vger.kernel.org Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Stable <stable@vger.kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2019-04-16CIFS: keep FileInfo handle live during oplock breakAurelien Aptel
In the oplock break handler, writing pending changes from pages puts the FileInfo handle. If the refcount reaches zero it closes the handle and waits for any oplock break handler to return, thus causing a deadlock. To prevent this situation: * We add a wait flag to cifsFileInfo_put() to decide whether we should wait for running/pending oplock break handlers * We keep an additionnal reference of the SMB FileInfo handle so that for the rest of the handler putting the handle won't close it. - The ref is bumped everytime we queue the handler via the cifs_queue_oplock_break() helper. - The ref is decremented at the end of the handler This bug was triggered by xfstest 464. Also important fix to address the various reports of oops in smb2_push_mandatory_locks Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com> CC: Stable <stable@vger.kernel.org>
2018-12-28cifs: Add support for failover in smb2_reconnect()Paulo Alcantara
After a successful failover in cifs_reconnect(), the smb2_reconnect() function will make sure to reconnect every tcon to new target server. For SMB2+. Signed-off-by: Paulo Alcantara <palcantara@suse.de> Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2018-12-28cifs: Add support for failover in cifs_mount()Paulo Alcantara
This patch adds support for failover when failing to connect in cifs_mount(). Signed-off-by: Paulo Alcantara <palcantara@suse.de> Reviewed-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2018-12-28cifs: check kzalloc returnJoe Perches
kzalloc can return NULL so an additional check is needed. While there is a check for ret_buf there is no check for the allocation of ret_buf->crfid.fid - this check is thus added. Both call-sites of tconInfoAlloc() check for NULL return of tconInfoAlloc() so returning NULL on failure of kzalloc() here seems appropriate. As the kzalloc() is the only thing here that can fail it is moved to the beginning so as not to initialize other resources on failure of kzalloc. Fixes: 3d4ef9a15343 ("smb3: fix redundant opens on root") Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2018-12-23cifs: Save TTL value when parsing DFS referralsPaulo Alcantara
This will be needed by DFS cache. Signed-off-by: Paulo Alcantara <palcantara@suse.de> Reviewed-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2018-12-23cifs: auto disable 'serverino' in dfs mountsAurelien Aptel
Different servers have different set of file ids. After failover, unique IDs will be different so we can't validate them. Signed-off-by: Aurelien Aptel <aaptel@suse.com> Reviewed-by: Paulo Alcantara <palcantara@suse.de> Signed-off-by: Steve French <stfrench@microsoft.com>
2018-11-01Merge branch 'work.afs' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull AFS updates from Al Viro: "AFS series, with some iov_iter bits included" * 'work.afs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (26 commits) missing bits of "iov_iter: Separate type from direction and use accessor functions" afs: Probe multiple fileservers simultaneously afs: Fix callback handling afs: Eliminate the address pointer from the address list cursor afs: Allow dumping of server cursor on operation failure afs: Implement YFS support in the fs client afs: Expand data structure fields to support YFS afs: Get the target vnode in afs_rmdir() and get a callback on it afs: Calc callback expiry in op reply delivery afs: Fix FS.FetchStatus delivery from updating wrong vnode afs: Implement the YFS cache manager service afs: Remove callback details from afs_callback_break struct afs: Commit the status on a new file/dir/symlink afs: Increase to 64-bit volume ID and 96-bit vnode ID for YFS afs: Don't invoke the server to read data beyond EOF afs: Add a couple of tracepoints to log I/O errors afs: Handle EIO from delivery function afs: Fix TTL on VL server and address lists afs: Implement VL server rotation afs: Improve FS server rotation error handling ...
2018-10-23smb3: show number of current open files in /proc/fs/cifs/StatsSteve French
To allow better debugging (for example applications with handle leaks, or complex reconnect scenarios) display the number of open files (on the client) and number of open server file handles for each tcon in /proc/fs/cifs/Stats. Note that open files on server is one larger than local due to handle caching (in this case of the root of the share). In this example there are two local open files, and three (two file and one directory handle) open on the server. Sample output: $ cat /proc/fs/cifs/Stats 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: 36 maximum at one time: 2 1) \\localhost\test SMBs: 69 Bytes read: 27 Bytes written: 0 Open files: 2 total (local), 3 open on server TreeConnects: 1 total 0 failed TreeDisconnects: 0 total 0 failed Creates: 19 total 0 failed Closes: 16 total 0 failed ... Signed-off-by: Steve French <stfrench@microsoft.com>
2018-10-24iov_iter: Separate type from direction and use accessor functionsDavid Howells
In the iov_iter struct, separate the iterator type from the iterator direction and use accessor functions to access them in most places. Convert a bunch of places to use switch-statements to access them rather then chains of bitwise-AND statements. This makes it easier to add further iterator types. Also, this can be more efficient as to implement a switch of small contiguous integers, the compiler can use ~50% fewer compare instructions than it has to use bitwise-and instructions. Further, cease passing the iterator type into the iterator setup function. The iterator function can set that itself. Only the direction is required. Signed-off-by: David Howells <dhowells@redhat.com>
2018-10-24iov_iter: Use accessor functionDavid Howells
Use accessor functions to access an iterator's type and direction. This allows for the possibility of using some other method of determining the type of iterator than if-chains with bitwise-AND conditions. Signed-off-by: David Howells <dhowells@redhat.com>
2018-09-12cifs: read overflow in is_valid_oplock_break()Dan Carpenter
We need to verify that the "data_offset" is within bounds. Reported-by: Dr Silvio Cesare of InfoSect <silvio.cesare@gmail.com> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Aurelien Aptel <aaptel@suse.com>
2018-08-07cifs: simple stats should always be enabledSteve French
CONFIG_CIFS_STATS should always be enabled as Pavel recently noted. Simple statistics are not a significant performance hit, and removing the ifdef simplifies the code slightly. Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-06-15CIFS: add iface info to struct cifs_sesAurelien Aptel
Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2018-06-15cifs: add lease tracking to the cached root fidRonnie Sahlberg
Use a read lease for the cached root fid so that we can detect when the content of the directory changes (via a break) at which time we close the handle. On next access to the root the handle will be reopened and cached again. Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2018-06-12treewide: Use array_size() in vmalloc()Kees Cook
The vmalloc() function has no 2-factor argument form, so multiplication factors need to be wrapped in array_size(). This patch replaces cases of: vmalloc(a * b) with: vmalloc(array_size(a, b)) as well as handling cases of: vmalloc(a * b * c) with: vmalloc(array3_size(a, b, c)) This does, however, attempt to ignore constant size factors like: vmalloc(4 * 1024) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( vmalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | vmalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( vmalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | vmalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | vmalloc( - sizeof(char) * (COUNT) + COUNT , ...) | vmalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | vmalloc( - sizeof(u8) * COUNT + COUNT , ...) | vmalloc( - sizeof(__u8) * COUNT + COUNT , ...) | vmalloc( - sizeof(char) * COUNT + COUNT , ...) | vmalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( vmalloc( - sizeof(TYPE) * (COUNT_ID) + array_size(COUNT_ID, sizeof(TYPE)) , ...) | vmalloc( - sizeof(TYPE) * COUNT_ID + array_size(COUNT_ID, sizeof(TYPE)) , ...) | vmalloc( - sizeof(TYPE) * (COUNT_CONST) + array_size(COUNT_CONST, sizeof(TYPE)) , ...) | vmalloc( - sizeof(TYPE) * COUNT_CONST + array_size(COUNT_CONST, sizeof(TYPE)) , ...) | vmalloc( - sizeof(THING) * (COUNT_ID) + array_size(COUNT_ID, sizeof(THING)) , ...) | vmalloc( - sizeof(THING) * COUNT_ID + array_size(COUNT_ID, sizeof(THING)) , ...) | vmalloc( - sizeof(THING) * (COUNT_CONST) + array_size(COUNT_CONST, sizeof(THING)) , ...) | vmalloc( - sizeof(THING) * COUNT_CONST + array_size(COUNT_CONST, sizeof(THING)) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ vmalloc( - SIZE * COUNT + array_size(COUNT, SIZE) , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( vmalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vmalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vmalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vmalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vmalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | vmalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | vmalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | vmalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( vmalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | vmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | vmalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | vmalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | vmalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | vmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( vmalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | vmalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | vmalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vmalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | vmalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vmalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vmalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vmalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( vmalloc(C1 * C2 * C3, ...) | vmalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants. @@ expression E1, E2; constant C1, C2; @@ ( vmalloc(C1 * C2, ...) | vmalloc( - E1 * E2 + array_size(E1, E2) , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-05CIFS: Introduce helper function to get page offset and length in smb_rqstLong Li
Introduce a function rqst_page_get_length to return the page offset and length for a given page in smb_rqst. This function is to be used by following patches. Signed-off-by: Long Li <longli@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2018-06-01cifs: remove struct smb2_hdrRonnie Sahlberg
struct smb2_hdr is now just a wrapper for smb2_sync_hdr. We can thus get rid of smb2_hdr completely and access the sync header directly. Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2018-05-27cifs: update calc_size to take a server argumentRonnie Sahlberg
and change the smb2 version to take heder_preamble_size into account instead of hardcoding it as 4 bytes. Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <smfrench@gmail.com>
2018-05-27smb3: fix redundant opens on rootSteve French
In SMB2/SMB3 unlike in cifs we unnecessarily open the root of the share over and over again in various places during mount and path revalidation and also in statfs. This patch cuts redundant traffic (opens and closes) by simply keeping the directory handle for the root around (and reopening it as needed on reconnect), so query calls don't require three round trips to copmlete - just one, and eases load on network, client and server (on mount alone, cuts network traffic by more than a third). Also add a new cifs mount parm "nohandlecache" to allow users whose servers might have resource constraints (eg in case they have a server with so many users connecting to it that this extra handle per mount could possibly be a resource concern). Signed-off-by: Steve French <smfrench@gmail.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2018-04-01CIFS: refactor crypto shash/sdesc allocation&freeAurelien Aptel
shash and sdesc and always allocated and freed together. * abstract this in new functions cifs_alloc_hash() and cifs_free_hash(). * make smb2/3 crypto allocation independent from each other. Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <smfrench@gmail.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> CC: Stable <stable@vger.kernel.org>
2018-01-26CIFS: zero sensitive data when freeingAurelien Aptel
also replaces memset()+kfree() by kzfree(). Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <smfrench@gmail.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com> Cc: <stable@vger.kernel.org>
2017-07-08[SMB3] Remove ifdef since SMB3 (and later) now STRONGLY preferredSteve French
Remove the CONFIG_CIFS_SMB2 ifdef and Kconfig option since they must always be on now. For various security reasons, SMB3 and later are STRONGLY preferred over CIFS and older dialects, and SMB3 (and later) will now be the default dialects so we do not want to allow them to be ifdeffed out. In the longer term, we may be able to make older CIFS support disableable in Kconfig with a new set of #ifdef, but we always want SMB3 and later support enabled. Signed-off-by: Steven French <smfrench@gmail.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2017-06-20CIFS: check if pages is null rather than bv for a failed allocationColin Ian King
pages is being allocated however a null check on bv is being used to see if the allocation failed. Fix this by checking if pages is null. Detected by CoverityScan, CID#1432974 ("Logically dead code") Fixes: ccf7f4088af2dd ("CIFS: Add asynchronous context to support kernel AIO") Signed-off-by: Colin Ian King <colin.king@canonical.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <smfrench@gmail.com>
2017-05-03CIFS: fix oplock break deadlocksRabin Vincent
When the final cifsFileInfo_put() is called from cifsiod and an oplock break work is queued, lockdep complains loudly: ============================================= [ INFO: possible recursive locking detected ] 4.11.0+ #21 Not tainted --------------------------------------------- kworker/0:2/78 is trying to acquire lock: ("cifsiod"){++++.+}, at: flush_work+0x215/0x350 but task is already holding lock: ("cifsiod"){++++.+}, at: process_one_work+0x255/0x8e0 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock("cifsiod"); lock("cifsiod"); *** DEADLOCK *** May be due to missing lock nesting notation 2 locks held by kworker/0:2/78: #0: ("cifsiod"){++++.+}, at: process_one_work+0x255/0x8e0 #1: ((&wdata->work)){+.+...}, at: process_one_work+0x255/0x8e0 stack backtrace: CPU: 0 PID: 78 Comm: kworker/0:2 Not tainted 4.11.0+ #21 Workqueue: cifsiod cifs_writev_complete Call Trace: dump_stack+0x85/0xc2 __lock_acquire+0x17dd/0x2260 ? match_held_lock+0x20/0x2b0 ? trace_hardirqs_off_caller+0x86/0x130 ? mark_lock+0xa6/0x920 lock_acquire+0xcc/0x260 ? lock_acquire+0xcc/0x260 ? flush_work+0x215/0x350 flush_work+0x236/0x350 ? flush_work+0x215/0x350 ? destroy_worker+0x170/0x170 __cancel_work_timer+0x17d/0x210 ? ___preempt_schedule+0x16/0x18 cancel_work_sync+0x10/0x20 cifsFileInfo_put+0x338/0x7f0 cifs_writedata_release+0x2a/0x40 ? cifs_writedata_release+0x2a/0x40 cifs_writev_complete+0x29d/0x850 ? preempt_count_sub+0x18/0xd0 process_one_work+0x304/0x8e0 worker_thread+0x9b/0x6a0 kthread+0x1b2/0x200 ? process_one_work+0x8e0/0x8e0 ? kthread_create_on_node+0x40/0x40 ret_from_fork+0x31/0x40 This is a real warning. Since the oplock is queued on the same workqueue this can deadlock if there is only one worker thread active for the workqueue (which will be the case during memory pressure when the rescuer thread is handling it). Furthermore, there is at least one other kind of hang possible due to the oplock break handling if there is only worker. (This can be reproduced without introducing memory pressure by having passing 1 for the max_active parameter of cifsiod.) cifs_oplock_break() can wait indefintely in the filemap_fdatawait() while the cifs_writev_complete() work is blocked: sysrq: SysRq : Show Blocked State task PC stack pid father kworker/0:1 D 0 16 2 0x00000000 Workqueue: cifsiod cifs_oplock_break Call Trace: __schedule+0x562/0xf40 ? mark_held_locks+0x4a/0xb0 schedule+0x57/0xe0 io_schedule+0x21/0x50 wait_on_page_bit+0x143/0x190 ? add_to_page_cache_lru+0x150/0x150 __filemap_fdatawait_range+0x134/0x190 ? do_writepages+0x51/0x70 filemap_fdatawait_range+0x14/0x30 filemap_fdatawait+0x3b/0x40 cifs_oplock_break+0x651/0x710 ? preempt_count_sub+0x18/0xd0 process_one_work+0x304/0x8e0 worker_thread+0x9b/0x6a0 kthread+0x1b2/0x200 ? process_one_work+0x8e0/0x8e0 ? kthread_create_on_node+0x40/0x40 ret_from_fork+0x31/0x40 dd D 0 683 171 0x00000000 Call Trace: __schedule+0x562/0xf40 ? mark_held_locks+0x29/0xb0 schedule+0x57/0xe0 io_schedule+0x21/0x50 wait_on_page_bit+0x143/0x190 ? add_to_page_cache_lru+0x150/0x150 __filemap_fdatawait_range+0x134/0x190 ? do_writepages+0x51/0x70 filemap_fdatawait_range+0x14/0x30 filemap_fdatawait+0x3b/0x40 filemap_write_and_wait+0x4e/0x70 cifs_flush+0x6a/0xb0 filp_close+0x52/0xa0 __close_fd+0xdc/0x150 SyS_close+0x33/0x60 entry_SYSCALL_64_fastpath+0x1f/0xbe Showing all locks held in the system: 2 locks held by kworker/0:1/16: #0: ("cifsiod"){.+.+.+}, at: process_one_work+0x255/0x8e0 #1: ((&cfile->oplock_break)){+.+.+.}, at: process_one_work+0x255/0x8e0 Showing busy workqueues and worker pools: workqueue cifsiod: flags=0xc pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/1 in-flight: 16:cifs_oplock_break delayed: cifs_writev_complete, cifs_echo_request pool 0: cpus=0 node=0 flags=0x0 nice=0 hung=0s workers=3 idle: 750 3 Fix these problems by creating a a new workqueue (with a rescuer) for the oplock break work. Signed-off-by: Rabin Vincent <rabinv@axis.com> Signed-off-by: Steve French <smfrench@gmail.com> CC: Stable <stable@vger.kernel.org>
2017-05-02CIFS: Add asynchronous context to support kernel AIOPavel Shilovsky
Currently the code doesn't recognize asynchronous calls passed by io_submit() and processes all calls synchronously. This is not what kernel AIO expects. This patch introduces a new async context that keeps track of all issued i/o requests and moves a response collecting procedure to a separate thread. This allows to return to a caller immediately for async calls and call iocb->ki_complete() once all requests are completed. For sync calls the current thread simply waits until all requests are completed. Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <smfrench@gmail.com>
2017-04-28cifs: don't check for failure from mempool_alloc()NeilBrown
mempool_alloc() cannot fail if the gfp flags allow it to sleep, and both GFP_FS allows for sleeping. So these tests of the return value from mempool_alloc() cannot be needed. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Steve French <smfrench@gmail.com>
2017-03-01CIFS: move DFS response parsing out of SMB1 codeAurelien Aptel
since the DFS payload is not tied to the SMB version we can: * isolate the DFS payload in its own struct, and include that struct in packet structs * move the function that parses the response to misc.c and make it work on the new DFS payload struct (add payload size and utf16 flag as a result). Signed-off-by: Aurelien Aptel <aaptel@suse.com> Acked-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <smfrench@gmail.com>
2016-10-12Clarify locking of cifs file and tcon structures and make more granularSteve French
Remove the global file_list_lock to simplify cifs/smb3 locking and have spinlocks that more closely match the information they are protecting. Add new tcon->open_file_lock and file->file_info_lock spinlocks. Locks continue to follow a heirachy, cifs_socket --> cifs_ses --> cifs_tcon --> cifs_file where global tcp_ses_lock still protects socket and cifs_ses, while the the newer locks protect the lower level structure's information (tcon and cifs_file respectively). CC: Stable <stable@vger.kernel.org> Signed-off-by: Steve French <steve.french@primarydata.com> Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Reviewed-by: Aurelien Aptel <aaptel@suse.com> Reviewed-by: Germano Percossi <germano.percossi@citrix.com>
2016-01-14Prepare for encryption support (first part). Add decryption and encryption ↵Steve French
key generation. Thanks to Metze for helping with this. Reviewed-by: Stefan Metzmacher <metze@samba.org> Signed-off-by: Steve French <steve.french@primarydata.com>
2015-04-15VFS: normal filesystems (and lustre): d_inode() annotationsDavid Howells
that's the bulk of filesystem drivers dealing with inodes of their own Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-12-07cifs: convert to print_hex_dump() instead of custom implementationAndy Shevchenko
This patch converts custom dumper to use native print_hex_dump() instead. The cifs_dump_mem() will have an offsets per each line which differs it from the original code. In the dump_smb() we may use native print_hex_dump() as well. It will show slightly different output in ASCII part when character is unprintable, otherwise it keeps same structure. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Steve French <steve.french@primarydata.com>
2014-08-11cifs: remove unused function cifs_oplock_break_waitVincent Stehlé
Commit 743162013d40 ("sched: Remove proliferation of wait_on_bit() action functions") has removed the call to cifs_oplock_break_wait, making this function unused; remove it. This fixes the following compilation warning: fs/cifs/misc.c:578:1: warning: ‘cifs_oplock_break_wait’ defined but not used [-Wunused-function] Signed-off-by: Vincent Stehlé <vincent.stehle@laposte.net> Cc: Steve French <sfrench@samba.org> Signed-off-by: Steve French <smfrench@gmail.com>
2014-08-09Merge branch 'for-next' of git://git.samba.org/sfrench/cifs-2.6Linus Torvalds
Pull CIFS updates from Steve French: "The most visible change in this set is the additional of multi-credit support for SMB2/SMB3 which dramatically improves the large file i/o performance for these dialects and significantly increases the maximum i/o size used on the wire for SMB2/SMB3. Also reconnection behavior after network failure is improved" * 'for-next' of git://git.samba.org/sfrench/cifs-2.6: (35 commits) Add worker function to set allocation size [CIFS] Fix incorrect hex vs. decimal in some debug print statements update CIFS TODO list Add Pavel to contributor list in cifs AUTHORS file Update cifs version CIFS: Fix STATUS_CANNOT_DELETE error mapping for SMB2 CIFS: Optimize readpages in a short read case on reconnects CIFS: Optimize cifs_user_read() in a short read case on reconnects CIFS: Improve indentation in cifs_user_read() CIFS: Fix possible buffer corruption in cifs_user_read() CIFS: Count got bytes in read_into_pages() CIFS: Use separate var for the number of bytes got in async read CIFS: Indicate reconnect with ECONNABORTED error code CIFS: Use multicredits for SMB 2.1/3 reads CIFS: Fix rsize usage for sync read CIFS: Fix rsize usage in user read CIFS: Separate page reading from user read CIFS: Fix rsize usage in readpages CIFS: Separate page search from readpages CIFS: Use multicredits for SMB 2.1/3 writes ...
2014-08-02[CIFS] Fix incorrect hex vs. decimal in some debug print statementsSteve French
Joe Perches and Hans Wennborg noticed that various places in the kernel were printing decimal numbers with 0x prefix. printk("0x%d") or equivalent This fixes the instances of this in the cifs driver. CC: Hans Wennborg <hans@hanshq.net> CC: Joe Perches <joe@perches.com> Signed-off-by: Steve French <smfrench@gmail.com>
2014-07-31cifs: replace code with free_rsp_buf()Sachin Prabhu
The functionality provided by free_rsp_buf() is duplicated in a number of places. Replace these instances with a call to free_rsp_buf(). Signed-off-by: Sachin Prabhu <sprabhu@redhat.com> Reviewed-by: Shirish Pargaonkar <spargaonkar@suse.com> Signed-off-by: Steve French <smfrench@gmail.com>
2014-07-16sched: Remove proliferation of wait_on_bit() action functionsNeilBrown
The current "wait_on_bit" interface requires an 'action' function to be provided which does the actual waiting. There are over 20 such functions, many of them identical. Most cases can be satisfied by one of just two functions, one which uses io_schedule() and one which just uses schedule(). So: Rename wait_on_bit and wait_on_bit_lock to wait_on_bit_action and wait_on_bit_lock_action to make it explicit that they need an action function. Introduce new wait_on_bit{,_lock} and wait_on_bit{,_lock}_io which are *not* given an action function but implicitly use a standard one. The decision to error-out if a signal is pending is now made based on the 'mode' argument rather than being encoded in the action function. All instances of the old wait_on_bit and wait_on_bit_lock which can use the new version have been changed accordingly and their action functions have been discarded. wait_on_bit{_lock} does not return any specific error code in the event of a signal so the caller must check for non-zero and interpolate their own error code as appropriate. The wait_on_bit() call in __fscache_wait_on_invalidate() was ambiguous as it specified TASK_UNINTERRUPTIBLE but used fscache_wait_bit_interruptible as an action function. David Howells confirms this should be uniformly "uninterruptible" The main remaining user of wait_on_bit{,_lock}_action is NFS which needs to use a freezer-aware schedule() call. A comment in fs/gfs2/glock.c notes that having multiple 'action' functions is useful as they display differently in the 'wchan' field of 'ps'. (and /proc/$PID/wchan). As the new bit_wait{,_io} functions are tagged "__sched", they will not show up at all, but something higher in the stack. So the distinction will still be visible, only with different function names (gds2_glock_wait versus gfs2_glock_dq_wait in the gfs2/glock.c case). Since first version of this patch (against 3.15) two new action functions appeared, on in NFS and one in CIFS. CIFS also now uses an action function that makes the same freezer aware schedule call as NFS. Signed-off-by: NeilBrown <neilb@suse.de> Acked-by: David Howells <dhowells@redhat.com> (fscache, keys) Acked-by: Steven Whitehouse <swhiteho@redhat.com> (gfs2) Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Steve French <sfrench@samba.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20140707051603.28027.72349.stgit@notabene.brown Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-16cifs: Wait for writebacks to complete before attempting write.Sachin Prabhu
Problem reported in Red Hat bz 1040329 for strict writes where we cache only when we hold oplock and write direct to the server when we don't. When we receive an oplock break, we first change the oplock value for the inode in cifsInodeInfo->oplock to indicate that we no longer hold the oplock before we enqueue a task to flush changes to the backing device. Once we have completed flushing the changes, we return the oplock to the server. There are 2 ways here where we can have data corruption 1) While we flush changes to the backing device as part of the oplock break, we can have processes write to the file. These writes check for the oplock, find none and attempt to write directly to the server. These direct writes made while we are flushing from cache could be overwritten by data being flushed from the cache causing data corruption. 2) While a thread runs in cifs_strict_writev, the machine could receive and process an oplock break after the thread has checked the oplock and found that it allows us to cache and before we have made changes to the cache. In that case, we end up with a dirty page in cache when we shouldn't have any. This will be flushed later and will overwrite all subsequent writes to the part of the file represented by this page. Before making any writes to the server, we need to confirm that we are not in the process of flushing data to the server and if we are, we should wait until the process is complete before we attempt the write. We should also wait for existing writes to complete before we process an oplock break request which changes oplock values. We add a version specific downgrade_oplock() operation to allow for differences in the oplock values set for the different smb versions. Cc: stable@vger.kernel.org Signed-off-by: Sachin Prabhu <sprabhu@redhat.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Pavel Shilovsky <piastry@etersoft.ru> Signed-off-by: Steve French <smfrench@gmail.com>
2013-11-02cifs: Make big endian multiplex ID sequences monotonic on the wireTim Gardner
The multiplex identifier (MID) in the SMB header is only ever used by the client, in conjunction with PID, to match responses from the server. As such, the endianess of the MID is not important. However, When tracing packet sequences on the wire, protocol analyzers such as wireshark display MID as little endian. It is much more informative for the on-the-wire MID sequences to match debug information emitted by the CIFS driver. Therefore, one should write and read MID in the SMB header assuming it is always little endian. Observed from wireshark during the protocol negotiation and session setup: Multiplex ID: 256 Multiplex ID: 256 Multiplex ID: 512 Multiplex ID: 512 Multiplex ID: 768 Multiplex ID: 768 After this patch on-the-wire MID values begin at 1 and increase monotonically. Introduce get_next_mid64() for the internal consumers that use the full 64 bit multiplex identifier. Introduce the helpers get_mid() and compare_mid() to make the endian translation clear. Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Tim Gardner <timg@tpi.com> Signed-off-by: Steve French <smfrench@gmail.com>
2013-10-28cifs: Remove redundant multiplex identifier check from check_smb_hdr()Tim Gardner
The only call site for check_smb_header() assigns 'mid' from the SMB packet, which is then checked again in check_smb_header(). This seems like redundant redundancy. Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Tim Gardner <timg@tpi.com> Signed-off-by: Steve French <smfrench@gmail.com>
2013-09-08CIFS: Replace clientCanCache* bools with an integerPavel Shilovsky
that prepare the code to handle different types of SMB2 leases. Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org> Signed-off-by: Steve French <smfrench@gmail.com>
2013-09-08cifs: Process post session setup code in respective dialect functions.Shirish Pargaonkar
Move the post (successful) session setup code to respective dialect routines. For smb1, session key is per smb connection. For smb2/smb3, session key is per smb session. If client and server do not require signing, free session key for smb1/2/3. If client and server require signing smb1 - Copy (kmemdup) session key for the first session to connection. Free session key of that and subsequent sessions on this connection. smb2 - For every session, keep the session key and free it when the session is being shutdown. smb3 - For every session, generate the smb3 signing key using the session key and then free the session key. There are two unrelated line formatting changes as well. Reviewed-by: Jeff Layton <jlayton@samba.org> Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com> Signed-off-by: Steve French <smfrench@gmail.com>
2013-06-24cifs: track the enablement of signing in the TCP_Server_InfoJeff Layton
Currently, we determine this according to flags in the sec_mode, flags in the global_secflags and via other methods. That makes the semantics very hard to follow and there are corner cases where we don't handle this correctly. Add a new bool to the TCP_Server_Info that acts as a simple flag to tell us whether signing is enabled on this connection or not, and fix up the places that need to determine this to use that flag. This is a bit weird for the SMB2 case, where signing is per-session. SMB2 needs work in this area already though. The existing SMB2 code has similar logic to what we're using here, so there should be no real change in behavior. These changes should make it easier to implement per-session signing in the future though. Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Pavel Shilovsky <piastry@etersoft.ru> Signed-off-by: Steve French <smfrench@gmail.com>
2013-05-04[CIFS] cifs: Rename cERROR and cFYI to cifs_dbgJoe Perches
It's not obvious from reading the macro names that these macros are for debugging. Convert the names to a single more typical kernel style cifs_dbg macro. cERROR(1, ...) -> cifs_dbg(VFS, ...) cFYI(1, ...) -> cifs_dbg(FYI, ...) cFYI(DBG2, ...) -> cifs_dbg(NOISY, ...) Move the terminating format newline from the macro to the call site. Add CONFIG_CIFS_DEBUG function cifs_vfs_err to emit the "CIFS VFS: " prefix for VFS messages. Size is reduced ~ 1% when CONFIG_CIFS_DEBUG is set (default y) $ size fs/cifs/cifs.ko* text data bss dec hex filename 265245 2525 132 267902 4167e fs/cifs/cifs.ko.new 268359 2525 132 271016 422a8 fs/cifs/cifs.ko.old Other miscellaneous changes around these conversions: o Miscellaneous typo fixes o Add terminating \n's to almost all formats and remove them from the macros to be more kernel style like. A few formats previously had defective \n's o Remove unnecessary OOM messages as kmalloc() calls dump_stack o Coalesce formats to make grep easier, added missing spaces when coalescing formats o Use %s, __func__ instead of embedded function name o Removed unnecessary "cifs: " prefixes o Convert kzalloc with multiply to kcalloc o Remove unused cifswarn macro Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <smfrench@gmail.com>
2013-02-13cifs: Convert struct cifs_sb_info to use kuids and kgidsEric W. Biederman
Cc: Steve French <smfrench@gmail.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2012-09-24CIFS: Fix fast lease break after open problemPavel Shilovsky
Now we walk though cifsFileInfo's list for every incoming lease break and look for an equivalent there. That approach misses lease breaks that come just after an open response - we don't have time to populate new cifsFileInfo structure to the list. Fix this by adding new list of pending opens and look for a lease there if we didn't find it in the list of cifsFileInfo structures. Signed-off-by: Pavel Shilovsky <pshilovsky@etersoft.ru> Signed-off-by: Steve French <sfrench@us.ibm.com>