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2018-09-25NFSD introduce async copy featureOlga Kornievskaia1-4/+17
Upon receiving a request for async copy, create a new kthread. If we get asynchronous request, make sure to copy the needed arguments/state from the stack before starting the copy. Then start the thread and reply back to the client indicating copy is asynchronous. nfsd_copy_file_range() will copy in a loop over the total number of bytes is needed to copy. In case a failure happens in the middle, we ignore the error and return how much we copied so far. Once done creating a workitem for the callback workqueue and send CB_OFFLOAD with the results. The lifetime of the copy stateid is bound to the vfs copy. This way we don't need to keep the nfsd_net structure for the callback. We could keep it around longer so that an OFFLOAD_STATUS that came late would still get results, but clients should be able to deal without that. We handle OFFLOAD_CANCEL by sending a signal to the copy thread and calling kthread_stop. A client should cancel any ongoing copies before calling DESTROY_CLIENT; if not, we return a CLIENT_BUSY error. If the client is destroyed for some other reason (lease expiration, or server shutdown), we must clean up any ongoing copies ourselves. Signed-off-by: Olga Kornievskaia <kolga@netapp.com> [colin.king@canonical.com: fix leak in error case] [bfields@fieldses.org: remove signalling, merge patches] Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-09-25NFSD OFFLOAD_CANCEL xdrOlga Kornievskaia1-1/+1
Signed-off-by: Olga Kornievskaia <kolga@netapp.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-09-25NFSD OFFLOAD_STATUS xdrOlga Kornievskaia1-2/+25
Signed-off-by: Olga Kornievskaia <kolga@netapp.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-08-09fs/nfsd: Delete invalid assignment statements in nfsd4_decode_exchange_idnixiaoming1-3/+1
READ_BUF(8); dummy = be32_to_cpup(p++); dummy = be32_to_cpup(p++); ... READ_BUF(4); dummy = be32_to_cpup(p++); Assigning value to "dummy" here, but that stored value is overwritten before it can be used. At the same time READ_BUF() will re-update the pointer p. delete invalid assignment statements Signed-off-by: nixiaoming <nixiaoming@huawei.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <trondmy@hammerspace.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-06-17nfsd4: support change_attr_type attributeJ. Bruce Fields1-0/+10
The change attribute is what is used by clients to revalidate their caches. Our server may use i_version or ctime for that purpose. Those choices behave slightly differently, and it may be useful to the client to know which we're using. This attribute tells the client that. The Linux client doesn't yet use this attribute yet, though. Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-06-17nfsd: fix NFSv4 time_delta attributeJ. Bruce Fields1-3/+26
Currently we return the worst-case value of 1 second in the time delta attribute. That's not terribly useful. Instead, return a value calculated from the time granularity supported by the filesystem and the system clock. Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-06-15Merge tag 'vfs-timespec64' of ↵Linus Torvalds1-2/+5
git://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground Pull inode timestamps conversion to timespec64 from Arnd Bergmann: "This is a late set of changes from Deepa Dinamani doing an automated treewide conversion of the inode and iattr structures from 'timespec' to 'timespec64', to push the conversion from the VFS layer into the individual file systems. As Deepa writes: 'The series aims to switch vfs timestamps to use struct timespec64. Currently vfs uses struct timespec, which is not y2038 safe. The series involves the following: 1. Add vfs helper functions for supporting struct timepec64 timestamps. 2. Cast prints of vfs timestamps to avoid warnings after the switch. 3. Simplify code using vfs timestamps so that the actual replacement becomes easy. 4. Convert vfs timestamps to use struct timespec64 using a script. This is a flag day patch. Next steps: 1. Convert APIs that can handle timespec64, instead of converting timestamps at the boundaries. 2. Update internal data structures to avoid timestamp conversions' Thomas Gleixner adds: 'I think there is no point to drag that out for the next merge window. The whole thing needs to be done in one go for the core changes which means that you're going to play that catchup game forever. Let's get over with it towards the end of the merge window'" * tag 'vfs-timespec64' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground: pstore: Remove bogus format string definition vfs: change inode times to use struct timespec64 pstore: Convert internal records to timespec64 udf: Simplify calls to udf_disk_stamp_to_time fs: nfs: get rid of memcpys for inode times ceph: make inode time prints to be long long lustre: Use long long type to print inode time fs: add timespec64_truncate()
2018-06-08nfsd: fix potential use-after-free in nfsd4_decode_getdeviceinfoScott Mayhew1-0/+2
When running a fuzz tester against a KASAN-enabled kernel, the following splat periodically occurs. The problem occurs when the test sends a GETDEVICEINFO request with a malformed xdr array (size but no data) for gdia_notify_types and the array size is > 0x3fffffff, which results in an overflow in the value of nbytes which is passed to read_buf(). If the array size is 0x40000000, 0x80000000, or 0xc0000000, then after the overflow occurs, the value of nbytes 0, and when that happens the pointer returned by read_buf() points to the end of the xdr data (i.e. argp->end) when really it should be returning NULL. Fix this by returning NFS4ERR_BAD_XDR if the array size is > 1000 (this value is arbitrary, but it's the same threshold used by nfsd4_decode_bitmap()... in could really be any value >= 1 since it's expected to get at most a single bitmap in gdia_notify_types). [ 119.256854] ================================================================== [ 119.257611] BUG: KASAN: use-after-free in nfsd4_decode_getdeviceinfo+0x5a4/0x5b0 [nfsd] [ 119.258422] Read of size 4 at addr ffff880113ada000 by task nfsd/538 [ 119.259146] CPU: 0 PID: 538 Comm: nfsd Not tainted 4.17.0+ #1 [ 119.259662] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.3-1.fc25 04/01/2014 [ 119.261202] Call Trace: [ 119.262265] dump_stack+0x71/0xab [ 119.263371] print_address_description+0x6a/0x270 [ 119.264609] kasan_report+0x258/0x380 [ 119.265854] ? nfsd4_decode_getdeviceinfo+0x5a4/0x5b0 [nfsd] [ 119.267291] nfsd4_decode_getdeviceinfo+0x5a4/0x5b0 [nfsd] [ 119.268549] ? nfs4svc_decode_compoundargs+0xa5b/0x13c0 [nfsd] [ 119.269873] ? nfsd4_decode_sequence+0x490/0x490 [nfsd] [ 119.271095] nfs4svc_decode_compoundargs+0xa5b/0x13c0 [nfsd] [ 119.272393] ? nfsd4_release_compoundargs+0x1b0/0x1b0 [nfsd] [ 119.273658] nfsd_dispatch+0x183/0x850 [nfsd] [ 119.274918] svc_process+0x161c/0x31a0 [sunrpc] [ 119.276172] ? svc_printk+0x190/0x190 [sunrpc] [ 119.277386] ? svc_xprt_release+0x451/0x680 [sunrpc] [ 119.278622] nfsd+0x2b9/0x430 [nfsd] [ 119.279771] ? nfsd_destroy+0x1c0/0x1c0 [nfsd] [ 119.281157] kthread+0x2db/0x390 [ 119.282347] ? kthread_create_worker_on_cpu+0xc0/0xc0 [ 119.283756] ret_from_fork+0x35/0x40 [ 119.286041] Allocated by task 436: [ 119.287525] kasan_kmalloc+0xa0/0xd0 [ 119.288685] kmem_cache_alloc+0xe9/0x1f0 [ 119.289900] get_empty_filp+0x7b/0x410 [ 119.291037] path_openat+0xca/0x4220 [ 119.292242] do_filp_open+0x182/0x280 [ 119.293411] do_sys_open+0x216/0x360 [ 119.294555] do_syscall_64+0xa0/0x2f0 [ 119.295721] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 119.298068] Freed by task 436: [ 119.299271] __kasan_slab_free+0x130/0x180 [ 119.300557] kmem_cache_free+0x78/0x210 [ 119.301823] rcu_process_callbacks+0x35b/0xbd0 [ 119.303162] __do_softirq+0x192/0x5ea [ 119.305443] The buggy address belongs to the object at ffff880113ada000 which belongs to the cache filp of size 256 [ 119.308556] The buggy address is located 0 bytes inside of 256-byte region [ffff880113ada000, ffff880113ada100) [ 119.311376] The buggy address belongs to the page: [ 119.312728] page:ffffea00044eb680 count:1 mapcount:0 mapping:0000000000000000 index:0xffff880113ada780 [ 119.314428] flags: 0x17ffe000000100(slab) [ 119.315740] raw: 0017ffe000000100 0000000000000000 ffff880113ada780 00000001000c0001 [ 119.317379] raw: ffffea0004553c60 ffffea00045c11e0 ffff88011b167e00 0000000000000000 [ 119.319050] page dumped because: kasan: bad access detected [ 119.321652] Memory state around the buggy address: [ 119.322993] ffff880113ad9f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 119.324515] ffff880113ad9f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 119.326087] >ffff880113ada000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 119.327547] ^ [ 119.328730] ffff880113ada080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 119.330218] ffff880113ada100: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 119.331740] ================================================================== Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-06-05vfs: change inode times to use struct timespec64Deepa Dinamani1-2/+5
struct timespec is not y2038 safe. Transition vfs to use y2038 safe struct timespec64 instead. The change was made with the help of the following cocinelle script. This catches about 80% of the changes. All the header file and logic changes are included in the first 5 rules. The rest are trivial substitutions. I avoid changing any of the function signatures or any other filesystem specific data structures to keep the patch simple for review. The script can be a little shorter by combining different cases. But, this version was sufficient for my usecase. virtual patch @ depends on patch @ identifier now; @@ - struct timespec + struct timespec64 current_time ( ... ) { - struct timespec now = current_kernel_time(); + struct timespec64 now = current_kernel_time64(); ... - return timespec_trunc( + return timespec64_trunc( ... ); } @ depends on patch @ identifier xtime; @@ struct \( iattr \| inode \| kstat \) { ... - struct timespec xtime; + struct timespec64 xtime; ... } @ depends on patch @ identifier t; @@ struct inode_operations { ... int (*update_time) (..., - struct timespec t, + struct timespec64 t, ...); ... } @ depends on patch @ identifier t; identifier fn_update_time =~ "update_time$"; @@ fn_update_time (..., - struct timespec *t, + struct timespec64 *t, ...) { ... } @ depends on patch @ identifier t; @@ lease_get_mtime( ... , - struct timespec *t + struct timespec64 *t ) { ... } @te depends on patch forall@ identifier ts; local idexpression struct inode *inode_node; identifier i_xtime =~ "^i_[acm]time$"; identifier ia_xtime =~ "^ia_[acm]time$"; identifier fn_update_time =~ "update_time$"; identifier fn; expression e, E3; local idexpression struct inode *node1; local idexpression struct inode *node2; local idexpression struct iattr *attr1; local idexpression struct iattr *attr2; local idexpression struct iattr attr; identifier i_xtime1 =~ "^i_[acm]time$"; identifier i_xtime2 =~ "^i_[acm]time$"; identifier ia_xtime1 =~ "^ia_[acm]time$"; identifier ia_xtime2 =~ "^ia_[acm]time$"; @@ ( ( - struct timespec ts; + struct timespec64 ts; | - struct timespec ts = current_time(inode_node); + struct timespec64 ts = current_time(inode_node); ) <+... when != ts ( - timespec_equal(&inode_node->i_xtime, &ts) + timespec64_equal(&inode_node->i_xtime, &ts) | - timespec_equal(&ts, &inode_node->i_xtime) + timespec64_equal(&ts, &inode_node->i_xtime) | - timespec_compare(&inode_node->i_xtime, &ts) + timespec64_compare(&inode_node->i_xtime, &ts) | - timespec_compare(&ts, &inode_node->i_xtime) + timespec64_compare(&ts, &inode_node->i_xtime) | ts = current_time(e) | fn_update_time(..., &ts,...) | inode_node->i_xtime = ts | node1->i_xtime = ts | ts = inode_node->i_xtime | <+... attr1->ia_xtime ...+> = ts | ts = attr1->ia_xtime | ts.tv_sec | ts.tv_nsec | btrfs_set_stack_timespec_sec(..., ts.tv_sec) | btrfs_set_stack_timespec_nsec(..., ts.tv_nsec) | - ts = timespec64_to_timespec( + ts = ... -) | - ts = ktime_to_timespec( + ts = ktime_to_timespec64( ...) | - ts = E3 + ts = timespec_to_timespec64(E3) | - ktime_get_real_ts(&ts) + ktime_get_real_ts64(&ts) | fn(..., - ts + timespec64_to_timespec(ts) ,...) ) ...+> ( <... when != ts - return ts; + return timespec64_to_timespec(ts); ...> ) | - timespec_equal(&node1->i_xtime1, &node2->i_xtime2) + timespec64_equal(&node1->i_xtime2, &node2->i_xtime2) | - timespec_equal(&node1->i_xtime1, &attr2->ia_xtime2) + timespec64_equal(&node1->i_xtime2, &attr2->ia_xtime2) | - timespec_compare(&node1->i_xtime1, &node2->i_xtime2) + timespec64_compare(&node1->i_xtime1, &node2->i_xtime2) | node1->i_xtime1 = - timespec_trunc(attr1->ia_xtime1, + timespec64_trunc(attr1->ia_xtime1, ...) | - attr1->ia_xtime1 = timespec_trunc(attr2->ia_xtime2, + attr1->ia_xtime1 = timespec64_trunc(attr2->ia_xtime2, ...) | - ktime_get_real_ts(&attr1->ia_xtime1) + ktime_get_real_ts64(&attr1->ia_xtime1) | - ktime_get_real_ts(&attr.ia_xtime1) + ktime_get_real_ts64(&attr.ia_xtime1) ) @ depends on patch @ struct inode *node; struct iattr *attr; identifier fn; identifier i_xtime =~ "^i_[acm]time$"; identifier ia_xtime =~ "^ia_[acm]time$"; expression e; @@ ( - fn(node->i_xtime); + fn(timespec64_to_timespec(node->i_xtime)); | fn(..., - node->i_xtime); + timespec64_to_timespec(node->i_xtime)); | - e = fn(attr->ia_xtime); + e = fn(timespec64_to_timespec(attr->ia_xtime)); ) @ depends on patch forall @ struct inode *node; struct iattr *attr; identifier i_xtime =~ "^i_[acm]time$"; identifier ia_xtime =~ "^ia_[acm]time$"; identifier fn; @@ { + struct timespec ts; <+... ( + ts = timespec64_to_timespec(node->i_xtime); fn (..., - &node->i_xtime, + &ts, ...); | + ts = timespec64_to_timespec(attr->ia_xtime); fn (..., - &attr->ia_xtime, + &ts, ...); ) ...+> } @ depends on patch forall @ struct inode *node; struct iattr *attr; struct kstat *stat; identifier ia_xtime =~ "^ia_[acm]time$"; identifier i_xtime =~ "^i_[acm]time$"; identifier xtime =~ "^[acm]time$"; identifier fn, ret; @@ { + struct timespec ts; <+... ( + ts = timespec64_to_timespec(node->i_xtime); ret = fn (..., - &node->i_xtime, + &ts, ...); | + ts = timespec64_to_timespec(node->i_xtime); ret = fn (..., - &node->i_xtime); + &ts); | + ts = timespec64_to_timespec(attr->ia_xtime); ret = fn (..., - &attr->ia_xtime, + &ts, ...); | + ts = timespec64_to_timespec(attr->ia_xtime); ret = fn (..., - &attr->ia_xtime); + &ts); | + ts = timespec64_to_timespec(stat->xtime); ret = fn (..., - &stat->xtime); + &ts); ) ...+> } @ depends on patch @ struct inode *node; struct inode *node2; identifier i_xtime1 =~ "^i_[acm]time$"; identifier i_xtime2 =~ "^i_[acm]time$"; identifier i_xtime3 =~ "^i_[acm]time$"; struct iattr *attrp; struct iattr *attrp2; struct iattr attr ; identifier ia_xtime1 =~ "^ia_[acm]time$"; identifier ia_xtime2 =~ "^ia_[acm]time$"; struct kstat *stat; struct kstat stat1; struct timespec64 ts; identifier xtime =~ "^[acmb]time$"; expression e; @@ ( ( node->i_xtime2 \| attrp->ia_xtime2 \| attr.ia_xtime2 \) = node->i_xtime1 ; | node->i_xtime2 = \( node2->i_xtime1 \| timespec64_trunc(...) \); | node->i_xtime2 = node->i_xtime1 = node->i_xtime3 = \(ts \| current_time(...) \); | node->i_xtime1 = node->i_xtime3 = \(ts \| current_time(...) \); | stat->xtime = node2->i_xtime1; | stat1.xtime = node2->i_xtime1; | ( node->i_xtime2 \| attrp->ia_xtime2 \) = attrp->ia_xtime1 ; | ( attrp->ia_xtime1 \| attr.ia_xtime1 \) = attrp2->ia_xtime2; | - e = node->i_xtime1; + e = timespec64_to_timespec( node->i_xtime1 ); | - e = attrp->ia_xtime1; + e = timespec64_to_timespec( attrp->ia_xtime1 ); | node->i_xtime1 = current_time(...); | node->i_xtime2 = node->i_xtime1 = node->i_xtime3 = - e; + timespec_to_timespec64(e); | node->i_xtime1 = node->i_xtime3 = - e; + timespec_to_timespec64(e); | - node->i_xtime1 = e; + node->i_xtime1 = timespec_to_timespec64(e); ) Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Cc: <anton@tuxera.com> Cc: <balbi@kernel.org> Cc: <bfields@fieldses.org> Cc: <darrick.wong@oracle.com> Cc: <dhowells@redhat.com> Cc: <dsterba@suse.com> Cc: <dwmw2@infradead.org> Cc: <hch@lst.de> Cc: <hirofumi@mail.parknet.co.jp> Cc: <hubcap@omnibond.com> Cc: <jack@suse.com> Cc: <jaegeuk@kernel.org> Cc: <jaharkes@cs.cmu.edu> Cc: <jslaby@suse.com> Cc: <keescook@chromium.org> Cc: <mark@fasheh.com> Cc: <miklos@szeredi.hu> Cc: <nico@linaro.org> Cc: <reiserfs-devel@vger.kernel.org> Cc: <richard@nod.at> Cc: <sage@redhat.com> Cc: <sfrench@samba.org> Cc: <swhiteho@redhat.com> Cc: <tj@kernel.org> Cc: <trond.myklebust@primarydata.com> Cc: <tytso@mit.edu> Cc: <viro@zeniv.linux.org.uk>
2018-05-07nfsd: restrict rd_maxcount to svc_max_payload in nfsd_encode_readdirScott Mayhew1-2/+3
nfsd4_readdir_rsize restricts rd_maxcount to svc_max_payload when estimating the size of the readdir reply, but nfsd_encode_readdir restricts it to INT_MAX when encoding the reply. This can result in log messages like "kernel: RPC request reserved 32896 but used 1049444". Restrict rd_dircount similarly (no reason it should be larger than svc_max_payload). Signed-off-by: Scott Mayhew <smayhew@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-04-03nfsd: fix incorrect umasksJ. Bruce Fields1-5/+3
We're neglecting to clear the umask after it's set, which can cause a later unrelated rpc to (incorrectly) use the same umask if it happens to be processed by the same thread. There's a more subtle problem here too: An NFSv4 compound request is decoded all in one pass before any operations are executed. Currently we're setting current->fs->umask at the time we decode the compound. In theory a single compound could contain multiple creates each setting a umask. In that case we'd end up using whichever umask was passed in the *last* operation as the umask for all the creates, whether that was correct or not. So, we should just be saving the umask at decode time and waiting to set it until we actually process the corresponding operation. In practice it's unlikely any client would do multiple creates in a single compound. And even if it did they'd likely be from the same process (hence carry the same umask). So this is a little academic, but we should get it right anyway. Fixes: 47057abde515 (nfsd: add support for the umask attribute) Cc: stable@vger.kernel.org Reported-by: Lucash Stach <l.stach@pengutronix.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-04-03nfsd: Add I/O trace points in the NFSv4 read procChuck Lever1-4/+6
NFSv4 read compound processing invokes nfsd_splice_read and nfs_readv directly, so the trace points currently in nfsd_read are not invoked for NFSv4 reads. Move the NFSD READ trace points to common helpers so that NFSv4 reads are captured. Also, record any local I/O error that occurs, the total count of bytes that were actually returned, and whether splice or vectored read was used. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-03-19nfsd: remove unsused "cp_consecutive" fieldJ. Bruce Fields1-2/+2
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-02-08NFSD: hide unused svcxdr_dupstr()Arnd Bergmann1-3/+2
There is now only one caller left for svcxdr_dupstr() and this is inside of an #ifdef, so we can get a warning when the option is disabled: fs/nfsd/nfs4xdr.c:241:1: error: 'svcxdr_dupstr' defined but not used [-Werror=unused-function] This changes the remaining caller to use a nicer IS_ENABLED() check, which lets the compiler drop the unused code silently. Fixes: e40d99e6183e ("NFSD: Clean up symlink argument XDR decoders") Suggested-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-02-08nfsd: store stat times in fill_pre_wcc() instead of inode timesAmir Goldstein1-1/+1
The time values in stat and inode may differ for overlayfs and stat time values are the correct ones to use. This is also consistent with the fact that fill_post_wcc() also stores stat time values. This means introducing a stat call that could fail, where previously we were just copying values out of the inode. To be conservative about changing behavior, we fall back to copying values out of the inode in the error case. It might be better just to clear fh_pre_saved (though note the BUG_ON in set_change_info). Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-02-08nfsd: return RESOURCE not GARBAGE_ARGS on too many opsJ. Bruce Fields1-2/+7
A client that sends more than a hundred ops in a single compound currently gets an rpc-level GARBAGE_ARGS error. It would be more helpful to return NFS4ERR_RESOURCE, since that gives the client a better idea how to recover (for example by splitting up the compound into smaller compounds). This is all a bit academic since we've never actually seen a reason for clients to send such long compounds, but we may as well fix it. While we're there, just use NFSD4_MAX_OPS_PER_COMPOUND == 16, the constant we already use in the 4.1 case, instead of hard-coding 100. Chances anyone actually uses even 16 ops per compound are small enough that I think there's a neglible risk or any regression. This fixes pynfs test COMP6. Reported-by: "Lu, Xinyu" <luxy.fnst@cn.fujitsu.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-09-05nfsd: Incoming xdr_bufs may have content in tail bufferChuck Lever1-0/+20
Since the beginning, svcsock has built a received RPC Call message by populating the xdr_buf's head, then placing the remaining message bytes in the xdr_buf's page list. The xdr_buf's tail is never populated. This means that an NFSv4 COMPOUND containing an NFS WRITE operation plus trailing operations has a page list that contains the WRITE data payload followed by the trailing operations. NFSv4 XDR decoders will not look in the xdr_buf's tail, ever, because svcsock never put anything there. To support transports that can pass the write payload in the xdr_buf's pagelist and trailing content in the xdr_buf's tail, introduce logic in READ_BUF that switches to the xdr_buf's tail vec when the decoder runs out of content in rq_arg.pages. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-09-05merge nfsd 4.13 bugfixes into nfsd for-4.14 branchJ. Bruce Fields1-4/+2
2017-08-24nfsd: Const-ify NFSv4 encoding and decoding ops arraysChuck Lever1-2/+2
Close an attack vector by moving the arrays of encoding and decoding methods to read-only memory. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-08-24nfsd4: individual encoders no longer see error casesJ. Bruce Fields1-206/+103
With a few exceptions, most individual encoders don't handle error cases. Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-08-24nfsd4: skip encoder in trivial error casesJ. Bruce Fields1-0/+3
Most encoders do nothing in the error case. But they can still screw things up in that case: most errors happen very early in rpc processing, possibly before argument fields are filled in and bounds-tested, so encoders that do anything other than immediately bail on error can easily crash in odd error cases. So just handle errors centrally most of the time to remove the chance of error. Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-08-24nfsd4: define ->op_release for compound opsJ. Bruce Fields1-6/+3
Run a separate ->op_release function if necessary instead of depending on the xdr encoder to do this. Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-08-24nfsd4: opdesc will be useful outside nfs4proc.cJ. Bruce Fields1-0/+1
Trivial cleanup, no change in behavior. Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-08-24nfsd: Limit end of page list when decoding NFSv4 WRITEChuck Lever1-4/+2
When processing an NFSv4 WRITE operation, argp->end should never point past the end of the data in the final page of the page list. Otherwise, nfsd4_decode_compound can walk into uninitialized memory. More critical, nfsd4_decode_write is failing to increment argp->pagelen when it increments argp->pagelist. This can cause later xdr decoders to assume more data is available than really is, which can cause server crashes on malformed requests. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-07-12nfsd4: factor ctime into change attributeJ. Bruce Fields1-1/+1
Factoring ctime into the nfsv4 change attribute gives us better properties than just i_version alone. Eventually we'll likely also expose this (as opposed to raw i_version) to userspace, at which point we'll want to move it to a common helper, called from either userspace or individual filesystems. For now, nfsd is the only user. Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-05-15sunrpc: properly type pc_encode callbacksChristoph Hellwig1-2/+3
Drop the resp argument as it can trivially be derived from the rqstp argument. With that all functions now have the same prototype, and we can remove the unsafe casting to kxdrproc_t. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-05-15sunrpc: properly type pc_decode callbacksChristoph Hellwig1-1/+3
Drop the argp argument as it can trivially be derived from the rqstp argument. With that all functions now have the same prototype, and we can remove the unsafe casting to kxdrproc_t. Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-05-15sunrpc: properly type pc_release callbacksChristoph Hellwig1-3/+1
Drop the p and resp arguments as they are always NULL or can trivially be derived from the rqstp argument. With that all functions now have the same prototype, and we can remove the unsafe casting to kxdrproc_t. Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-05-10nfsd: Fix up the "supattr_exclcreat" attributesTrond Myklebust1-3/+8
If an NFSv4 client asks us for the supattr_exclcreat, then we must not return attributes that are unsupported by this minor version. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Fixes: 75976de6556f ("NFSD: Return word2 bitmask if setting security..,") Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-05-10nfsd: encoders mustn't use unitialized values in error casesJ. Bruce Fields1-4/+4
In error cases, lgp->lg_layout_type may be out of bounds; so we shouldn't be using it until after the check of nfserr. This was seen to crash nfsd threads when the server receives a LAYOUTGET request with a large layout type. GETDEVICEINFO has the same problem. Reported-by: Ari Kauppi <Ari.Kauppi@synopsys.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-03-02statx: Add a system call to make enhanced file info availableDavid Howells1-2/+2
Add a system call to make extended file information available, including file creation and some attribute flags where available through the underlying filesystem. The getattr inode operation is altered to take two additional arguments: a u32 request_mask and an unsigned int flags that indicate the synchronisation mode. This change is propagated to the vfs_getattr*() function. Functions like vfs_stat() are now inline wrappers around new functions vfs_statx() and vfs_statx_fd() to reduce stack usage. ======== OVERVIEW ======== The idea was initially proposed as a set of xattrs that could be retrieved with getxattr(), but the general preference proved to be for a new syscall with an extended stat structure. A number of requests were gathered for features to be included. The following have been included: (1) Make the fields a consistent size on all arches and make them large. (2) Spare space, request flags and information flags are provided for future expansion. (3) Better support for the y2038 problem [Arnd Bergmann] (tv_sec is an __s64). (4) Creation time: The SMB protocol carries the creation time, which could be exported by Samba, which will in turn help CIFS make use of FS-Cache as that can be used for coherency data (stx_btime). This is also specified in NFSv4 as a recommended attribute and could be exported by NFSD [Steve French]. (5) Lightweight stat: Ask for just those details of interest, and allow a netfs (such as NFS) to approximate anything not of interest, possibly without going to the server [Trond Myklebust, Ulrich Drepper, Andreas Dilger] (AT_STATX_DONT_SYNC). (6) Heavyweight stat: Force a netfs to go to the server, even if it thinks its cached attributes are up to date [Trond Myklebust] (AT_STATX_FORCE_SYNC). And the following have been left out for future extension: (7) Data version number: Could be used by userspace NFS servers [Aneesh Kumar]. Can also be used to modify fill_post_wcc() in NFSD which retrieves i_version directly, but has just called vfs_getattr(). It could get it from the kstat struct if it used vfs_xgetattr() instead. (There's disagreement on the exact semantics of a single field, since not all filesystems do this the same way). (8) BSD stat compatibility: Including more fields from the BSD stat such as creation time (st_btime) and inode generation number (st_gen) [Jeremy Allison, Bernd Schubert]. (9) Inode generation number: Useful for FUSE and userspace NFS servers [Bernd Schubert]. (This was asked for but later deemed unnecessary with the open-by-handle capability available and caused disagreement as to whether it's a security hole or not). (10) Extra coherency data may be useful in making backups [Andreas Dilger]. (No particular data were offered, but things like last backup timestamp, the data version number and the DOS archive bit would come into this category). (11) Allow the filesystem to indicate what it can/cannot provide: A filesystem can now say it doesn't support a standard stat feature if that isn't available, so if, for instance, inode numbers or UIDs don't exist or are fabricated locally... (This requires a separate system call - I have an fsinfo() call idea for this). (12) Store a 16-byte volume ID in the superblock that can be returned in struct xstat [Steve French]. (Deferred to fsinfo). (13) Include granularity fields in the time data to indicate the granularity of each of the times (NFSv4 time_delta) [Steve French]. (Deferred to fsinfo). (14) FS_IOC_GETFLAGS value. These could be translated to BSD's st_flags. Note that the Linux IOC flags are a mess and filesystems such as Ext4 define flags that aren't in linux/fs.h, so translation in the kernel may be a necessity (or, possibly, we provide the filesystem type too). (Some attributes are made available in stx_attributes, but the general feeling was that the IOC flags were to ext[234]-specific and shouldn't be exposed through statx this way). (15) Mask of features available on file (eg: ACLs, seclabel) [Brad Boyer, Michael Kerrisk]. (Deferred, probably to fsinfo. Finding out if there's an ACL or seclabal might require extra filesystem operations). (16) Femtosecond-resolution timestamps [Dave Chinner]. (A __reserved field has been left in the statx_timestamp struct for this - if there proves to be a need). (17) A set multiple attributes syscall to go with this. =============== NEW SYSTEM CALL =============== The new system call is: int ret = statx(int dfd, const char *filename, unsigned int flags, unsigned int mask, struct statx *buffer); The dfd, filename and flags parameters indicate the file to query, in a similar way to fstatat(). There is no equivalent of lstat() as that can be emulated with statx() by passing AT_SYMLINK_NOFOLLOW in flags. There is also no equivalent of fstat() as that can be emulated by passing a NULL filename to statx() with the fd of interest in dfd. Whether or not statx() synchronises the attributes with the backing store can be controlled by OR'ing a value into the flags argument (this typically only affects network filesystems): (1) AT_STATX_SYNC_AS_STAT tells statx() to behave as stat() does in this respect. (2) AT_STATX_FORCE_SYNC will require a network filesystem to synchronise its attributes with the server - which might require data writeback to occur to get the timestamps correct. (3) AT_STATX_DONT_SYNC will suppress synchronisation with the server in a network filesystem. The resulting values should be considered approximate. mask is a bitmask indicating the fields in struct statx that are of interest to the caller. The user should set this to STATX_BASIC_STATS to get the basic set returned by stat(). It should be noted that asking for more information may entail extra I/O operations. buffer points to the destination for the data. This must be 256 bytes in size. ====================== MAIN ATTRIBUTES RECORD ====================== The following structures are defined in which to return the main attribute set: struct statx_timestamp { __s64 tv_sec; __s32 tv_nsec; __s32 __reserved; }; struct statx { __u32 stx_mask; __u32 stx_blksize; __u64 stx_attributes; __u32 stx_nlink; __u32 stx_uid; __u32 stx_gid; __u16 stx_mode; __u16 __spare0[1]; __u64 stx_ino; __u64 stx_size; __u64 stx_blocks; __u64 __spare1[1]; struct statx_timestamp stx_atime; struct statx_timestamp stx_btime; struct statx_timestamp stx_ctime; struct statx_timestamp stx_mtime; __u32 stx_rdev_major; __u32 stx_rdev_minor; __u32 stx_dev_major; __u32 stx_dev_minor; __u64 __spare2[14]; }; The defined bits in request_mask and stx_mask are: STATX_TYPE Want/got stx_mode & S_IFMT STATX_MODE Want/got stx_mode & ~S_IFMT STATX_NLINK Want/got stx_nlink STATX_UID Want/got stx_uid STATX_GID Want/got stx_gid STATX_ATIME Want/got stx_atime{,_ns} STATX_MTIME Want/got stx_mtime{,_ns} STATX_CTIME Want/got stx_ctime{,_ns} STATX_INO Want/got stx_ino STATX_SIZE Want/got stx_size STATX_BLOCKS Want/got stx_blocks STATX_BASIC_STATS [The stuff in the normal stat struct] STATX_BTIME Want/got stx_btime{,_ns} STATX_ALL [All currently available stuff] stx_btime is the file creation time, stx_mask is a bitmask indicating the data provided and __spares*[] are where as-yet undefined fields can be placed. Time fields are structures with separate seconds and nanoseconds fields plus a reserved field in case we want to add even finer resolution. Note that times will be negative if before 1970; in such a case, the nanosecond fields will also be negative if not zero. The bits defined in the stx_attributes field convey information about a file, how it is accessed, where it is and what it does. The following attributes map to FS_*_FL flags and are the same numerical value: STATX_ATTR_COMPRESSED File is compressed by the fs STATX_ATTR_IMMUTABLE File is marked immutable STATX_ATTR_APPEND File is append-only STATX_ATTR_NODUMP File is not to be dumped STATX_ATTR_ENCRYPTED File requires key to decrypt in fs Within the kernel, the supported flags are listed by: KSTAT_ATTR_FS_IOC_FLAGS [Are any other IOC flags of sufficient general interest to be exposed through this interface?] New flags include: STATX_ATTR_AUTOMOUNT Object is an automount trigger These are for the use of GUI tools that might want to mark files specially, depending on what they are. Fields in struct statx come in a number of classes: (0) stx_dev_*, stx_blksize. These are local system information and are always available. (1) stx_mode, stx_nlinks, stx_uid, stx_gid, stx_[amc]time, stx_ino, stx_size, stx_blocks. These will be returned whether the caller asks for them or not. The corresponding bits in stx_mask will be set to indicate whether they actually have valid values. If the caller didn't ask for them, then they may be approximated. For example, NFS won't waste any time updating them from the server, unless as a byproduct of updating something requested. If the values don't actually exist for the underlying object (such as UID or GID on a DOS file), then the bit won't be set in the stx_mask, even if the caller asked for the value. In such a case, the returned value will be a fabrication. Note that there are instances where the type might not be valid, for instance Windows reparse points. (2) stx_rdev_*. This will be set only if stx_mode indicates we're looking at a blockdev or a chardev, otherwise will be 0. (3) stx_btime. Similar to (1), except this will be set to 0 if it doesn't exist. ======= TESTING ======= The following test program can be used to test the statx system call: samples/statx/test-statx.c Just compile and run, passing it paths to the files you want to examine. The file is built automatically if CONFIG_SAMPLES is enabled. Here's some example output. Firstly, an NFS directory that crosses to another FSID. Note that the AUTOMOUNT attribute is set because transiting this directory will cause d_automount to be invoked by the VFS. [root@andromeda ~]# /tmp/test-statx -A /warthog/data statx(/warthog/data) = 0 results=7ff Size: 4096 Blocks: 8 IO Block: 1048576 directory Device: 00:26 Inode: 1703937 Links: 125 Access: (3777/drwxrwxrwx) Uid: 0 Gid: 4041 Access: 2016-11-24 09:02:12.219699527+0000 Modify: 2016-11-17 10:44:36.225653653+0000 Change: 2016-11-17 10:44:36.225653653+0000 Attributes: 0000000000001000 (-------- -------- -------- -------- -------- -------- ---m---- --------) Secondly, the result of automounting on that directory. [root@andromeda ~]# /tmp/test-statx /warthog/data statx(/warthog/data) = 0 results=7ff Size: 4096 Blocks: 8 IO Block: 1048576 directory Device: 00:27 Inode: 2 Links: 125 Access: (3777/drwxrwxrwx) Uid: 0 Gid: 4041 Access: 2016-11-24 09:02:12.219699527+0000 Modify: 2016-11-17 10:44:36.225653653+0000 Change: 2016-11-17 10:44:36.225653653+0000 Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-02-17NFSD: Reserve adequate space for LOCKT operationKinglong Mee1-5/+5
After tightening the OP_LOCKT reply size estimate, we can get warnings like: [11512.783519] RPC request reserved 124 but used 152 [11512.813624] RPC request reserved 108 but used 136 Signed-off-by: Kinglong Mee <kinglongmee@gmail.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-02-06NFSDv4: use export cache flushtime for changeid on V4ROOT objects.NeilBrown1-3/+7
If you change the set of filesystems that are exported, then the contents of various directories in the NFSv4 pseudo-root is likely to change. However the change-id of those directories is currently tied to the underlying directory, so the client may not see the changes in a timely fashion. This patch changes the change-id number to be derived from the "flush_time" of the export cache. Whenever any changes are made to the set of exported filesystems, this flush_time is updated. The result is that clients see changes to the set of exported filesystems much more quickly, often immediately. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-01-31nfsd: opt in to labeled nfs per exportJ. Bruce Fields1-1/+4
Currently turning on NFSv4.2 results in 4.2 clients suddenly seeing the individual file labels as they're set on the server. This is not what they've previously seen, and not appropriate in may cases. (In particular, if clients have heterogenous security policies then one client's labels may not even make sense to another.) Labeled NFS should be opted in only in those cases when the administrator knows it makes sense. It's helpful to be able to turn 4.2 on by default, and otherwise the protocol upgrade seems free of regressions. So, default labeled NFS to off and provide an export flag to reenable it. Users wanting labeled NFS support on an export will henceforth need to: - make sure 4.2 support is enabled on client and server (as before), and - upgrade the server nfs-utils to a version supporting the new "security_label" export flag. - set that "security_label" flag on the export. This is commit may be seen as a regression to anyone currently depending on security labels. We believe those cases are currently rare. Reported-by: tibbs@math.uh.edu Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-01-31nfsd: constify nfsd_suppatttrsJ. Bruce Fields1-1/+1
To keep me from accidentally writing to this again.... Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-01-31NFSD: pass an integer for stable type to nfsd_vfs_writeKinglong Mee1-1/+1
After fae5096ad217 "nfsd: assume writeable exportabled filesystems have f_sync" we no longer modify this argument. This is just cleanup, no change in functionality. Signed-off-by: Kinglong Mee <kinglongmee@gmail.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-01-12nfsd: fix supported attributes for acl & labelsJ. Bruce Fields1-1/+3
Oops--in 916d2d844afd I moved some constants into an array for convenience, but here I'm accidentally writing to that array. The effect is that if you ever encounter a filesystem lacking support for ACLs or security labels, then all queries of supported attributes will report that attribute as unsupported from then on. Fixes: 916d2d844afd "nfsd: clean up supported attribute handling" Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-12-17Merge uncontroversial parts of branch 'readlink' of ↵Linus Torvalds1-4/+4
git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs Pull partial readlink cleanups from Miklos Szeredi. This is the uncontroversial part of the readlink cleanup patch-set that simplifies the default readlink handling. Miklos and Al are still discussing the rest of the series. * git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs: vfs: make generic_readlink() static vfs: remove ".readlink = generic_readlink" assignments vfs: default to generic_readlink() vfs: replace calling i_op->readlink with vfs_readlink() proc/self: use generic_readlink ecryptfs: use vfs_get_link() bad_inode: add missing i_op initializers
2016-12-15nfsd: add support for the umask attributeAndreas Gruenbacher1-5/+21
Clients can set the umask attribute when creating files to cause the server to apply it always except when inheriting permissions from the parent directory. That way, the new files will end up with the same permissions as files created locally. See https://tools.ietf.org/html/draft-ietf-nfsv4-umask-02 for more details. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-12-09vfs: replace calling i_op->readlink with vfs_readlink()Miklos Szeredi1-4/+4
Also check d_is_symlink() in callers instead of inode->i_op->readlink because following patches will allow NULL ->readlink for symlinks. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-11-01nfsd: catch errors in decode_fattr earlierJ. Bruce Fields1-6/+9
3c8e03166ae2 "NFSv4: do exact check about attribute specified" fixed some handling of unsupported-attribute errors, but it also delayed checking for unwriteable attributes till after we decode them. This could lead to odd behavior in the case a client attemps to set an attribute we don't know about followed by one we try to parse. In that case the parser for the known attribute will attempt to parse the unknown attribute. It should fail in some safe way, but the error might at least be incorrect (probably bad_xdr instead of inval). So, it's better to do that check at the start. As far as I know this doesn't cause any problems with current clients but it might be a minor issue e.g. if we encounter a future client that supports a new attribute that we currently don't. Cc: Yu Zhiguo <yuzg@cn.fujitsu.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-11-01nfsd: clean up supported attribute handlingJ. Bruce Fields1-14/+24
Minor cleanup, no change in behavior. Provide helpers for some common attribute bitmap operations. Drop some comments that just echo the code. Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-10-07NFSD: Implement the COPY callAnna Schumaker1-2/+61
I only implemented the sync version of this call, since it's the easiest. I can simply call vfs_copy_range() and have the vfs do the right thing for the filesystem being exported. Signed-off-by: Anna Schumaker <bjschuma@netapp.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-09-23nfsd: fix dprintk in nfsd4_encode_getdeviceinfoJeff Layton1-1/+1
nfserr is big-endian, so we should convert it to host-endian before printing it. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-07-15nfsd: allow nfsd to advertise multiple layout typesJeff Layton1-16/+14
If the underlying filesystem supports multiple layout types, then there is little reason not to advertise that fact to clients and let them choose what type to use. Turn the ex_layout_type field into a bitfield. For each supported layout type, we set a bit in that field. When the client requests a layout, ensure that the bit for that layout type is set. When the client requests attributes, send back a list of supported types. Signed-off-by: Jeff Layton <jlayton@poochiereds.net> Reviewed-by: Weston Andros Adamson <dros@primarydata.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-07-13nfsd: implement machine credential support for some operationsAndrew Elble1-28/+23
This addresses the conundrum referenced in RFC5661 18.35.3, and will allow clients to return state to the server using the machine credentials. The biggest part of the problem is that we need to allow the client to send a compound op with integrity/privacy on mounts that don't have it enabled. Add server support for properly decoding and using spo_must_enforce and spo_must_allow bits. Add support for machine credentials to be used for CLOSE, OPEN_DOWNGRADE, LOCKU, DELEGRETURN, and TEST/FREE STATEID. Implement a check so as to not throw WRONGSEC errors when these operations are used if integrity/privacy isn't turned on. Without this, Linux clients with credentials that expired while holding delegations were getting stuck in an endless loop. Signed-off-by: Andrew Elble <aweits@rit.edu> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-03-23nfsd: use short read as well as i_size to set eofBenjamin Coddington1-4/+7
Use the result of a local read to determine when to set the eof flag. This allows us to return the location of the end of the file atomically at the time of the read. Signed-off-by: Benjamin Coddington <bcodding@redhat.com> [bfields: add some documentation] Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-03-01nfsd: Update NFS server comments related to RDMA supportChuck Lever1-1/+1
The server does indeed now support NFSv4.1 on RDMA transports. It does not support shifting an RDMA-capable TCP transport (such as iWARP) to RDMA mode. Reported-by: Shirley Ma <shirley.ma@oracle.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-03-01nfsd4: fix bad bounds checkingJ. Bruce Fields1-5/+8
A number of spots in the xdr decoding follow a pattern like n = be32_to_cpup(p++); READ_BUF(n + 4); where n is a u32. The only bounds checking is done in READ_BUF itself, but since it's checking (n + 4), it won't catch cases where n is very large, (u32)(-4) or higher. I'm not sure exactly what the consequences are, but we've seen crashes soon after. Instead, just break these up into two READ_BUF()s. Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-01-12Merge branch 'work.misc' of ↵Linus Torvalds1-4/+4
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull misc vfs updates from Al Viro: "All kinds of stuff. That probably should've been 5 or 6 separate branches, but by the time I'd realized how large and mixed that bag had become it had been too close to -final to play with rebasing. Some fs/namei.c cleanups there, memdup_user_nul() introduction and switching open-coded instances, burying long-dead code, whack-a-mole of various kinds, several new helpers for ->llseek(), assorted cleanups and fixes from various people, etc. One piece probably deserves special mention - Neil's lookup_one_len_unlocked(). Similar to lookup_one_len(), but gets called without ->i_mutex and tries to avoid ever taking it. That, of course, means that it's not useful for any directory modifications, but things like getting inode attributes in nfds readdirplus are fine with that. I really should've asked for moratorium on lookup-related changes this cycle, but since I hadn't done that early enough... I *am* asking for that for the coming cycle, though - I'm going to try and get conversion of i_mutex to rwsem with ->lookup() done under lock taken shared. There will be a patch closer to the end of the window, along the lines of the one Linus had posted last May - mechanical conversion of ->i_mutex accesses to inode_lock()/inode_unlock()/inode_trylock()/ inode_is_locked()/inode_lock_nested(). To quote Linus back then: ----- | This is an automated patch using | | sed 's/mutex_lock(&\(.*\)->i_mutex)/inode_lock(\1)/' | sed 's/mutex_unlock(&\(.*\)->i_mutex)/inode_unlock(\1)/' | sed 's/mutex_lock_nested(&\(.*\)->i_mutex,[ ]*I_MUTEX_\([A-Z0-9_]*\))/inode_lock_nested(\1, I_MUTEX_\2)/' | sed 's/mutex_is_locked(&\(.*\)->i_mutex)/inode_is_locked(\1)/' | sed 's/mutex_trylock(&\(.*\)->i_mutex)/inode_trylock(\1)/' | | with a very few manual fixups ----- I'm going to send that once the ->i_mutex-affecting stuff in -next gets mostly merged (or when Linus says he's about to stop taking merges)" * 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits) nfsd: don't hold i_mutex over userspace upcalls fs:affs:Replace time_t with time64_t fs/9p: use fscache mutex rather than spinlock proc: add a reschedule point in proc_readfd_common() logfs: constify logfs_block_ops structures fcntl: allow to set O_DIRECT flag on pipe fs: __generic_file_splice_read retry lookup on AOP_TRUNCATED_PAGE fs: xattr: Use kvfree() [s390] page_to_phys() always returns a multiple of PAGE_SIZE nbd: use ->compat_ioctl() fs: use block_device name vsprintf helper lib/vsprintf: add %*pg format specifier fs: use gendisk->disk_name where possible poll: plug an unused argument to do_poll amdkfd: don't open-code memdup_user() cdrom: don't open-code memdup_user() rsxx: don't open-code memdup_user() mtip32xx: don't open-code memdup_user() [um] mconsole: don't open-code memdup_user_nul() [um] hostaudio: don't open-code memdup_user() ...