summaryrefslogtreecommitdiffstats
path: root/fs/ceph
Commit message (Collapse)AuthorAgeFilesLines
* ceph: fix fscache invalidationJeff Layton2021-05-222-0/+2
| | | | | | | | | | | [ Upstream commit 10a7052c7868bc7bc72d947f5aac6f768928db87 ] Ensure that we invalidate the fscache whenever we invalidate the pagecache. Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* ceph: fix race in concurrent __ceph_remove_cap invocationsLuis Henriques2020-12-291-2/+9
| | | | | | | | | | | | | | | | | | | | | commit e5cafce3ad0f8652d6849314d951459c2bff7233 upstream. A NULL pointer dereference may occur in __ceph_remove_cap with some of the callbacks used in ceph_iterate_session_caps, namely trim_caps_cb and remove_session_caps_cb. Those callers hold the session->s_mutex, so they are prevented from concurrent execution, but ceph_evict_inode does not. Since the callers of this function hold the i_ceph_lock, the fix is simply a matter of returning immediately if caps->ci is NULL. Cc: stable@vger.kernel.org URL: https://tracker.ceph.com/issues/43272 Suggested-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Luis Henriques <lhenriques@suse.de> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ceph: promote to unsigned long long before shiftingMatthew Wilcox (Oracle)2020-11-101-1/+1
| | | | | | | | | | | | | | commit c403c3a2fbe24d4ed33e10cabad048583ebd4edf upstream. On 32-bit systems, this shift will overflow for files larger than 4GB. Cc: stable@vger.kernel.org Fixes: 61f68816211e ("ceph: check caps in filemap_fault and page_mkwrite") Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ceph: fix potential race in ceph_check_capsJeff Layton2020-10-011-1/+13
| | | | | | | | | | | | | | [ Upstream commit dc3da0461cc4b76f2d0c5b12247fcb3b520edbbf ] Nothing ensures that session will still be valid by the time we dereference the pointer. Take and put a reference. In principle, we should always be able to get a reference here, but throw a warning if that's ever not the case. Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* ceph: don't allow setlease on cephfsJeff Layton2020-09-121-0/+1
| | | | | | | | | | | | | | | | [ Upstream commit 496ceaf12432b3d136dcdec48424312e71359ea7 ] Leases don't currently work correctly on kcephfs, as they are not broken when caps are revoked. They could eventually be implemented similarly to how we did them in libcephfs, but for now don't allow them. [ idryomov: no need for simple_nosetlease() in ceph_dir_fops and ceph_snapdir_fops ] Signed-off-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* ceph: fix potential mdsc use-after-free crashXiubo Li2020-09-031-1/+13
| | | | | | | | | | | | | | | | | | | | | [ Upstream commit fa9967734227b44acb1b6918033f9122dc7825b9 ] Make sure the delayed work stopped before releasing the resources. cancel_delayed_work_sync() will only guarantee that the work finishes executing if the work is already in the ->worklist. That means after the cancel_delayed_work_sync() returns, it will leave the work requeued if it was rearmed at the end. That can lead to a use after free once the work struct is freed. Fix it by flushing the delayed work instead of trying to cancel it, and ensure that the work doesn't rearm if the mdsc is stopping. URL: https://tracker.ceph.com/issues/46293 Signed-off-by: Xiubo Li <xiubli@redhat.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* ceph: fix double unlock in handle_cap_export()Wu Bo2020-05-271-0/+1
| | | | | | | | | | | | | | [ Upstream commit 4d8e28ff3106b093d98bfd2eceb9b430c70a8758 ] If the ceph_mdsc_open_export_target_session() return fails, it will do a "goto retry", but the session mutex has already been unlocked. Re-lock the mutex in that case to ensure that we don't unlock it twice. Signed-off-by: Wu Bo <wubo40@huawei.com> Reviewed-by: "Yan, Zheng" <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* ceph: don't skip updating wanted caps when cap is staleYan, Zheng2020-05-021-2/+6
| | | | | | | | | | | | | | | | | | | [ Upstream commit 0aa971b6fd3f92afef6afe24ef78d9bb14471519 ] 1. try_get_cap_refs() fails to get caps and finds that mds_wanted does not include what it wants. It returns -ESTALE. 2. ceph_get_caps() calls ceph_renew_caps(). ceph_renew_caps() finds that inode has cap, so it calls ceph_check_caps(). 3. ceph_check_caps() finds that issued caps (without checking if it's stale) already includes caps wanted by open file, so it skips updating wanted caps. Above events can cause an infinite loop inside ceph_get_caps(). Signed-off-by: "Yan, Zheng" <zyan@redhat.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* ceph: return ceph_mdsc_do_request() errors from __get_parent()Qiujun Huang2020-05-021-0/+5
| | | | | | | | | | | | | [ Upstream commit c6d50296032f0b97473eb2e274dc7cc5d0173847 ] Return the error returned by ceph_mdsc_do_request(). Otherwise, r_target_inode ends up being NULL this ends up returning ENOENT regardless of the error. Signed-off-by: Qiujun Huang <hqjagain@gmail.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* ceph: canonicalize server path in placeIlya Dryomov2020-04-132-92/+28
| | | | | | | | | | | | | | | | | | | | | | commit b27a939e8376a3f1ed09b9c33ef44d20f18ec3d0 upstream. syzbot reported that 4fbc0c711b24 ("ceph: remove the extra slashes in the server path") had caused a regression where an allocation could be done under a spinlock -- compare_mount_options() is called by sget_fc() with sb_lock held. We don't really need the supplied server path, so canonicalize it in place and compare it directly. To make this work, the leading slash is kept around and the logic in ceph_real_mount() to skip it is restored. CEPH_MSG_CLIENT_SESSION now reports the same (i.e. canonicalized) path, with the leading slash of course. Fixes: 4fbc0c711b24 ("ceph: remove the extra slashes in the server path") Reported-by: syzbot+98704a51af8e3d9425a9@syzkaller.appspotmail.com Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Luis Henriques <lhenriques@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ceph: remove the extra slashes in the server pathXiubo Li2020-04-131-19/+99
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 4fbc0c711b2464ee1551850b85002faae0b775d5 upstream. It's possible to pass the mount helper a server path that has more than one contiguous slash character. For example: $ mount -t ceph 192.168.195.165:40176:/// /mnt/cephfs/ In the MDS server side the extra slashes of the server path will be treated as snap dir, and then we can get the following debug logs: ceph: mount opening path // ceph: open_root_inode opening '//' ceph: fill_trace 0000000059b8a3bc is_dentry 0 is_target 1 ceph: alloc_inode 00000000dc4ca00b ceph: get_inode created new inode 00000000dc4ca00b 1.ffffffffffffffff ino 1 ceph: get_inode on 1=1.ffffffffffffffff got 00000000dc4ca00b And then when creating any new file or directory under the mount point, we can hit the following BUG_ON in ceph_fill_trace(): BUG_ON(ceph_snap(dir) != dvino.snap); Have the client ignore the extra slashes in the server path when mounting. This will also canonicalize the path, so that identical mounts can be consilidated. 1) "//mydir1///mydir//" 2) "/mydir1/mydir" 3) "/mydir1/mydir/" Regardless of the internal treatment of these paths, the kernel still stores the original string including the leading '/' for presentation to userland. URL: https://tracker.ceph.com/issues/42771 Signed-off-by: Xiubo Li <xiubli@redhat.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Luis Henriques <lhenriques@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ceph: fix dentry leak in ceph_readdir_prepopulateYan, Zheng2019-11-281-1/+0
| | | | | | | | | [ Upstream commit c58f450bd61511d897efc2ea472c69630635b557 ] Signed-off-by: "Yan, Zheng" <zyan@redhat.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* ceph: fix use-after-free in __ceph_remove_cap()Luis Henriques2019-11-121-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit ea60ed6fcf29eebc78f2ce91491e6309ee005a01 upstream. KASAN reports a use-after-free when running xfstest generic/531, with the following trace: [ 293.903362] kasan_report+0xe/0x20 [ 293.903365] rb_erase+0x1f/0x790 [ 293.903370] __ceph_remove_cap+0x201/0x370 [ 293.903375] __ceph_remove_caps+0x4b/0x70 [ 293.903380] ceph_evict_inode+0x4e/0x360 [ 293.903386] evict+0x169/0x290 [ 293.903390] __dentry_kill+0x16f/0x250 [ 293.903394] dput+0x1c6/0x440 [ 293.903398] __fput+0x184/0x330 [ 293.903404] task_work_run+0xb9/0xe0 [ 293.903410] exit_to_usermode_loop+0xd3/0xe0 [ 293.903413] do_syscall_64+0x1a0/0x1c0 [ 293.903417] entry_SYSCALL_64_after_hwframe+0x44/0xa9 This happens because __ceph_remove_cap() may queue a cap release (__ceph_queue_cap_release) which can be scheduled before that cap is removed from the inode list with rb_erase(&cap->ci_node, &ci->i_caps); And, when this finally happens, the use-after-free will occur. This can be fixed by removing the cap from the inode list before being removed from the session list, and thus eliminating the risk of an UAF. Cc: stable@vger.kernel.org Signed-off-by: Luis Henriques <lhenriques@suse.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ceph: reconnect connection if session hang in opening stateErqi Chen2019-10-171-1/+3
| | | | | | | | | | | | | | | | | | | | [ Upstream commit 71a228bc8d65900179e37ac309e678f8c523f133 ] If client mds session is evicted in CEPH_MDS_SESSION_OPENING state, mds won't send session msg to client, and delayed_work skip CEPH_MDS_SESSION_OPENING state session, the session hang forever. Allow ceph_con_keepalive to reconnect a session in OPENING to avoid session hang. Also, ensure that we skip sessions in RESTARTING and REJECTED states since those states can't be resurrected by issuing a keepalive. Link: https://tracker.ceph.com/issues/41551 Signed-off-by: Erqi Chen chenerqi@gmail.com Reviewed-by: "Yan, Zheng" <zyan@redhat.com> Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* ceph: fix directories inode i_blkbits initializationLuis Henriques2019-10-171-1/+6
| | | | | | | | | | | | | | | | | | | | | [ Upstream commit 750670341a24cb714e624e0fd7da30900ad93752 ] When filling an inode with info from the MDS, i_blkbits is being initialized using fl_stripe_unit, which contains the stripe unit in bytes. Unfortunately, this doesn't make sense for directories as they have fl_stripe_unit set to '0'. This means that i_blkbits will be set to 0xff, causing an UBSAN undefined behaviour in i_blocksize(): UBSAN: Undefined behaviour in ./include/linux/fs.h:731:12 shift exponent 255 is too large for 32-bit type 'int' Fix this by initializing i_blkbits to CEPH_BLOCK_SHIFT if fl_stripe_unit is zero. Signed-off-by: Luis Henriques <lhenriques@suse.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* ceph: fix buffer free while holding i_ceph_lock in fill_inode()Luis Henriques2019-09-101-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit af8a85a41734f37b67ba8ce69d56b685bee4ac48 ] Calling ceph_buffer_put() in fill_inode() may result in freeing the i_xattrs.blob buffer while holding the i_ceph_lock. This can be fixed by postponing the call until later, when the lock is released. The following backtrace was triggered by fstests generic/070. BUG: sleeping function called from invalid context at mm/vmalloc.c:2283 in_atomic(): 1, irqs_disabled(): 0, pid: 3852, name: kworker/0:4 6 locks held by kworker/0:4/3852: #0: 000000004270f6bb ((wq_completion)ceph-msgr){+.+.}, at: process_one_work+0x1b8/0x5f0 #1: 00000000eb420803 ((work_completion)(&(&con->work)->work)){+.+.}, at: process_one_work+0x1b8/0x5f0 #2: 00000000be1c53a4 (&s->s_mutex){+.+.}, at: dispatch+0x288/0x1476 #3: 00000000559cb958 (&mdsc->snap_rwsem){++++}, at: dispatch+0x2eb/0x1476 #4: 000000000d5ebbae (&req->r_fill_mutex){+.+.}, at: dispatch+0x2fc/0x1476 #5: 00000000a83d0514 (&(&ci->i_ceph_lock)->rlock){+.+.}, at: fill_inode.isra.0+0xf8/0xf70 CPU: 0 PID: 3852 Comm: kworker/0:4 Not tainted 5.2.0+ #441 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58-prebuilt.qemu.org 04/01/2014 Workqueue: ceph-msgr ceph_con_workfn Call Trace: dump_stack+0x67/0x90 ___might_sleep.cold+0x9f/0xb1 vfree+0x4b/0x60 ceph_buffer_release+0x1b/0x60 fill_inode.isra.0+0xa9b/0xf70 ceph_fill_trace+0x13b/0xc70 ? dispatch+0x2eb/0x1476 dispatch+0x320/0x1476 ? __mutex_unlock_slowpath+0x4d/0x2a0 ceph_con_workfn+0xc97/0x2ec0 ? process_one_work+0x1b8/0x5f0 process_one_work+0x244/0x5f0 worker_thread+0x4d/0x3e0 kthread+0x105/0x140 ? process_one_work+0x5f0/0x5f0 ? kthread_park+0x90/0x90 ret_from_fork+0x3a/0x50 Signed-off-by: Luis Henriques <lhenriques@suse.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* ceph: fix buffer free while holding i_ceph_lock in __ceph_setxattr()Luis Henriques2019-09-101-2/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 86968ef21596515958d5f0a40233d02be78ecec0 ] Calling ceph_buffer_put() in __ceph_setxattr() may end up freeing the i_xattrs.prealloc_blob buffer while holding the i_ceph_lock. This can be fixed by postponing the call until later, when the lock is released. The following backtrace was triggered by fstests generic/117. BUG: sleeping function called from invalid context at mm/vmalloc.c:2283 in_atomic(): 1, irqs_disabled(): 0, pid: 650, name: fsstress 3 locks held by fsstress/650: #0: 00000000870a0fe8 (sb_writers#8){.+.+}, at: mnt_want_write+0x20/0x50 #1: 00000000ba0c4c74 (&type->i_mutex_dir_key#6){++++}, at: vfs_setxattr+0x55/0xa0 #2: 000000008dfbb3f2 (&(&ci->i_ceph_lock)->rlock){+.+.}, at: __ceph_setxattr+0x297/0x810 CPU: 1 PID: 650 Comm: fsstress Not tainted 5.2.0+ #437 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58-prebuilt.qemu.org 04/01/2014 Call Trace: dump_stack+0x67/0x90 ___might_sleep.cold+0x9f/0xb1 vfree+0x4b/0x60 ceph_buffer_release+0x1b/0x60 __ceph_setxattr+0x2b4/0x810 __vfs_setxattr+0x66/0x80 __vfs_setxattr_noperm+0x59/0xf0 vfs_setxattr+0x81/0xa0 setxattr+0x115/0x230 ? filename_lookup+0xc9/0x140 ? rcu_read_lock_sched_held+0x74/0x80 ? rcu_sync_lockdep_assert+0x2e/0x60 ? __sb_start_write+0x142/0x1a0 ? mnt_want_write+0x20/0x50 path_setxattr+0xba/0xd0 __x64_sys_lsetxattr+0x24/0x30 do_syscall_64+0x50/0x1c0 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7ff23514359a Signed-off-by: Luis Henriques <lhenriques@suse.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* ceph: return -ERANGE if virtual xattr value didn't fit in bufferJeff Layton2019-08-061-7/+7
| | | | | | | | | | | | | | | | | | | | [ Upstream commit 3b421018f48c482bdc9650f894aa1747cf90e51d ] The getxattr manpage states that we should return ERANGE if the destination buffer size is too small to hold the value. ceph_vxattrcb_layout does this internally, but we should be doing this for all vxattrs. Fix the only caller of getxattr_cb to check the returned size against the buffer length and return -ERANGE if it doesn't fit. Drop the same check in ceph_vxattrcb_layout and just rely on the caller to handle it. Signed-off-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: "Yan, Zheng" <zyan@redhat.com> Acked-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* ceph: fix improper use of smp_mb__before_atomic()Andrea Parri2019-08-061-1/+6
| | | | | | | | | | | | | | | | | [ Upstream commit 749607731e26dfb2558118038c40e9c0c80d23b5 ] This barrier only applies to the read-modify-write operations; in particular, it does not apply to the atomic64_set() primitive. Replace the barrier with an smp_mb(). Fixes: fdd4e15838e59 ("ceph: rework dcache readdir") Reported-by: "Paul E. McKenney" <paulmck@linux.ibm.com> Reported-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Andrea Parri <andrea.parri@amarulasolutions.com> Reviewed-by: "Yan, Zheng" <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* ceph: hold i_ceph_lock when removing caps for freeing inodeYan, Zheng2019-08-041-2/+5
| | | | | | | | | | | | | commit d6e47819721ae2d9d090058ad5570a66f3c42e39 upstream. ceph_d_revalidate(, LOOKUP_RCU) may call __ceph_caps_issued_mask() on a freeing inode. Signed-off-by: "Yan, Zheng" <zyan@redhat.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ceph: flush dirty inodes before proceeding with remountJeff Layton2019-05-251-0/+7
| | | | | | | | | | | | | | | | | commit 00abf69dd24f4444d185982379c5cc3bb7b6d1fc upstream. xfstest generic/452 was triggering a "Busy inodes after umount" warning. ceph was allowing the mount to go read-only without first flushing out dirty inodes in the cache. Ensure we sync out the filesystem before allowing a remount to proceed. Cc: stable@vger.kernel.org Link: http://tracker.ceph.com/issues/39571 Signed-off-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: "Yan, Zheng" <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ceph: fix use-after-free on symlink traversalAl Viro2019-05-041-1/+1
| | | | | | | | | | | | | [ Upstream commit daf5cc27eed99afdea8d96e71b89ba41f5406ef6 ] free the symlink body after the same RCU delay we have for freeing the struct inode itself, so that traversal during RCU pathwalk wouldn't step into freed memory. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Sasha Levin (Microsoft) <sashal@kernel.org>
* ceph: fix ci->i_head_snapc leakYan, Zheng2019-05-022-1/+15
| | | | | | | | | | | | | | | | commit 37659182bff1eeaaeadcfc8f853c6d2b6dbc3f47 upstream. We missed two places that i_wrbuffer_ref_head, i_wr_ref, i_dirty_caps and i_flushing_caps may change. When they are all zeros, we should free i_head_snapc. Cc: stable@vger.kernel.org Link: https://tracker.ceph.com/issues/38224 Reported-and-tested-by: Luis Henriques <lhenriques@suse.com> Signed-off-by: "Yan, Zheng" <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ceph: ensure d_name stability in ceph_dentry_hash()Jeff Layton2019-05-021-1/+5
| | | | | | | | | | | | | commit 76a495d666e5043ffc315695f8241f5e94a98849 upstream. Take the d_lock here to ensure that d_name doesn't change. Cc: stable@vger.kernel.org Signed-off-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: "Yan, Zheng" <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ceph: avoid repeatedly adding inode to mdsc->snap_flush_listYan, Zheng2019-02-271-1/+2
| | | | | | | | | | | | | commit 04242ff3ac0abbaa4362f97781dac268e6c3541a upstream. Otherwise, mdsc->snap_flush_list may get corrupted. Cc: stable@vger.kernel.org Signed-off-by: "Yan, Zheng" <zyan@redhat.com> Reviewed-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ceph: don't update importing cap's mseq when handing cap exportYan, Zheng2019-01-131-1/+0
| | | | | | | | | | | | | | | | | commit 3c1392d4c49962a31874af14ae9ff289cb2b3851 upstream. Updating mseq makes client think importer mds has accepted all prior cap messages and importer mds knows what caps client wants. Actually some cap messages may have been dropped because of mseq mismatch. If mseq is left untouched, importing cap's mds_wanted later will get reset by cap import message. Cc: stable@vger.kernel.org Signed-off-by: "Yan, Zheng" <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* libceph: add authorizer challengeIlya Dryomov2018-12-081-0/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 6daca13d2e72bedaaacfc08f873114c9307d5aea upstream. When a client authenticates with a service, an authorizer is sent with a nonce to the service (ceph_x_authorize_[ab]) and the service responds with a mutation of that nonce (ceph_x_authorize_reply). This lets the client verify the service is who it says it is but it doesn't protect against a replay: someone can trivially capture the exchange and reuse the same authorizer to authenticate themselves. Allow the service to reject an initial authorizer with a random challenge (ceph_x_authorize_challenge). The client then has to respond with an updated authorizer proving they are able to decrypt the service's challenge and that the new authorizer was produced for this specific connection instance. The accepting side requires this challenge and response unconditionally if the client side advertises they have CEPHX_V2 feature bit. This addresses CVE-2018-1128. Link: http://tracker.ceph.com/issues/24836 Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Reviewed-by: Sage Weil <sage@redhat.com> Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* libceph: drop len argument of *verify_authorizer_reply()Ilya Dryomov2018-12-081-2/+2
| | | | | | | | | | | | | commit 0dde584882ade13dc9708d611fbf69b0ae8a9e48 upstream. The length of the reply is protocol-dependent - for cephx it's ceph_x_authorize_reply. Nothing sensible can be passed from the messenger layer anyway. Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Reviewed-by: Sage Weil <sage@redhat.com> Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Revert "ceph: fix dentry leak in splice_dentry()"Yan, Zheng2018-11-211-2/+6
| | | | | | | | | | | | | | | | commit efe328230dc01aa0b1269aad0b5fae73eea4677a upstream. This reverts commit 8b8f53af1ed9df88a4c0fbfdf3db58f62060edf3. splice_dentry() is used by three places. For two places, req->r_dentry is passed to splice_dentry(). In the case of error, req->r_dentry does not get updated. So splice_dentry() should not drop reference. Cc: stable@vger.kernel.org # 4.18+ Signed-off-by: "Yan, Zheng" <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ceph: fix dentry leak in splice_dentry()Yan, Zheng2018-08-241-0/+1
| | | | | | | | | | | | | [ Upstream commit 8b8f53af1ed9df88a4c0fbfdf3db58f62060edf3 ] In any case, d_splice_alias() does not drop reference of original dentry. Signed-off-by: "Yan, Zheng" <zyan@redhat.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ceph: fix dentry leak when failing to init debugfsChengguang Xu2018-05-301-11/+5
| | | | | | | | | | | | | | | [ Upstream commit 18106734b512664a8541026519ce4b862498b6c3 ] When failing from ceph_fs_debugfs_init() in ceph_real_mount(), there is lack of dput of root_dentry and it causes slab errors, so change the calling order of ceph_fs_debugfs_init() and open_root_dentry() and do some cleanups to avoid this issue. Signed-off-by: Chengguang Xu <cgxu519@icloud.com> Reviewed-by: "Yan, Zheng" <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ceph: only dirty ITER_IOVEC pages for direct readYan, Zheng2018-04-081-3/+6
| | | | | | | | | | | | | | | | | | | | commit 85784f9395987a422fa04263e7c0fb13da11eb5c upstream. If a page is already locked, attempting to dirty it leads to a deadlock in lock_page(). This is what currently happens to ITER_BVEC pages when a dio-enabled loop device is backed by ceph: $ losetup --direct-io /dev/loop0 /mnt/cephfs/img $ xfs_io -c 'pread 0 4k' /dev/loop0 Follow other file systems and only dirty ITER_IOVEC pages. Cc: stable@kernel.org Signed-off-by: "Yan, Zheng" <zyan@redhat.com> Reviewed-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ceph: drop negative child dentries before try pruning inode's aliasYan, Zheng2017-12-201-4/+38
| | | | | | | | | | | | | commit 040d786032bf59002d374b86d75b04d97624005c upstream. Negative child dentry holds reference on inode's alias, it makes d_prune_aliases() do nothing. Signed-off-by: "Yan, Zheng" <zyan@redhat.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ceph: unlock dangling spinlock in try_flush_caps()Jeff Layton2017-11-021-1/+4
| | | | | | | | | | | | | | | | | | commit 6c2838fbdedb9b72a81c931d49e56b229b6cdbca upstream. sparse warns: fs/ceph/caps.c:2042:9: warning: context imbalance in 'try_flush_caps' - wrong count at exit We need to exit this function with the lock unlocked, but a couple of cases leave it locked. Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: "Yan, Zheng" <zyan@redhat.com> Reviewed-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ceph: clean up unsafe d_parent accesses in build_dentry_pathJeff Layton2017-10-211-2/+7
| | | | | | | | | | | | | | | | | [ Upstream commit c6b0b656ca24ede6657abb4a2cd910fa9c1879ba ] While we hold a reference to the dentry when build_dentry_path is called, we could end up racing with a rename that changes d_parent. Handle that situation correctly, by using the rcu_read_lock to ensure that the parent dentry and inode stick around long enough to safely check ceph_snap and ceph_ino. Link: http://tracker.ceph.com/issues/18148 Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Yan, Zheng <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ceph: fix bogus endianness change in ceph_ioctl_set_layoutJeff Layton2017-10-211-2/+2
| | | | | | | | | | | | | | | | | [ Upstream commit 24c149ad6914d349d8b64749f20f3f8ea5031fe0 ] sparse says: fs/ceph/ioctl.c:100:28: warning: cast to restricted __le64 preferred_osd is a __s64 so we don't need to do any conversion. Also, just remove the cast in ceph_ioctl_get_layout as it's not needed. Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Sage Weil <sage@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ceph: don't update_dentry_lease unless we actually got oneJeff Layton2017-10-211-2/+2
| | | | | | | | | | | | | [ Upstream commit 80d025ffede88969f6adf7266fbdedfd5641148a ] This if block updates the dentry lease even in the case where the MDS didn't grant one. Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Yan, Zheng <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ceph: fix readpage from fscacheYan, Zheng2017-09-072-18/+18
| | | | | | | | | | | | | | | commit dd2bc473482eedc60c29cf00ad12568ce40ce511 upstream. ceph_readpage() unlocks page prematurely prematurely in the case that page is reading from fscache. Caller of readpage expects that page is uptodate when it get unlocked. So page shoule get locked by completion callback of fscache_read_or_alloc_pages() Signed-off-by: "Yan, Zheng" <zyan@redhat.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ceph: fix race in concurrent readdirYan, Zheng2017-07-271-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 84583cfb973c4313955c6231cc9cb3772d280b15 upstream. For a large directory, program needs to issue multiple readdir syscalls to get all dentries. When there are multiple programs read the directory concurrently. Following sequence of events can happen. - program calls readdir with pos = 2. ceph sends readdir request to mds. The reply contains N1 entries. ceph adds these N1 entries to readdir cache. - program calls readdir with pos = N1+2. The readdir is satisfied by the readdir cache, N2 entries are returned. (Other program calls readdir in the middle, which fills the cache) - program calls readdir with pos = N1+N2+2. ceph sends readdir request to mds. The reply contains N3 entries and it reaches directory end. ceph adds these N3 entries to the readdir cache and marks directory complete. The second readdir call does not update fi->readdir_cache_idx. ceph add the last N3 entries to wrong places. Signed-off-by: "Yan, Zheng" <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ceph: choose readdir frag based on previous readdir replyYan, Zheng2017-07-121-7/+12
| | | | | | | | | | | | | | | | | | | | | commit b50c2de51e611da90cf3cf04c058f7e9bbe79e93 upstream. The dirfragtree is lazily updated, it's not always accurate. Infinite loops happens in following circumstance. - client send request to read frag A - frag A has been fragmented into frag B and C. So mds fills the reply with contents of frag B - client wants to read next frag C. ceph_choose_frag(frag value of C) return frag A. The fix is using previous readdir reply to calculate next readdir frag when possible. Signed-off-by: "Yan, Zheng" <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* fs: add i_blocksize()Fabian Frederick2017-06-141-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | commit 93407472a21b82f39c955ea7787e5bc7da100642 upstream. Replace all 1 << inode->i_blkbits and (1 << inode->i_blkbits) in fs branch. This patch also fixes multiple checkpatch warnings: WARNING: Prefer 'unsigned int' to bare use of 'unsigned' Thanks to Andrew Morton for suggesting more appropriate function instead of macro. [geliangtang@gmail.com: truncate: use i_blocksize()] Link: http://lkml.kernel.org/r/9c8b2cd83c8f5653805d43debde9fa8817e02fc4.1484895804.git.geliangtang@gmail.com Link: http://lkml.kernel.org/r/1481319905-10126-1-git-send-email-fabf@skynet.be Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: Geliang Tang <geliangtang@gmail.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ceph: fix memory leak in __ceph_setxattr()Luis Henriques2017-05-201-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit eeca958dce0a9231d1969f86196653eb50fcc9b3 upstream. The ceph_inode_xattr needs to be released when removing an xattr. Easily reproducible running the 'generic/020' test from xfstests or simply by doing: attr -s attr0 -V 0 /mnt/test && attr -r attr0 /mnt/test While there, also fix the error path. Here's the kmemleak splat: unreferenced object 0xffff88001f86fbc0 (size 64): comm "attr", pid 244, jiffies 4294904246 (age 98.464s) hex dump (first 32 bytes): 40 fa 86 1f 00 88 ff ff 80 32 38 1f 00 88 ff ff @........28..... 00 01 00 00 00 00 ad de 00 02 00 00 00 00 ad de ................ backtrace: [<ffffffff81560199>] kmemleak_alloc+0x49/0xa0 [<ffffffff810f3e5b>] kmem_cache_alloc+0x9b/0xf0 [<ffffffff812b157e>] __ceph_setxattr+0x17e/0x820 [<ffffffff812b1c57>] ceph_set_xattr_handler+0x37/0x40 [<ffffffff8111fb4b>] __vfs_removexattr+0x4b/0x60 [<ffffffff8111fd37>] vfs_removexattr+0x77/0xd0 [<ffffffff8111fdd1>] removexattr+0x41/0x60 [<ffffffff8111fe65>] path_removexattr+0x75/0xa0 [<ffffffff81120aeb>] SyS_lremovexattr+0xb/0x10 [<ffffffff81564b20>] entry_SYSCALL_64_fastpath+0x13/0x94 [<ffffffffffffffff>] 0xffffffffffffffff Signed-off-by: Luis Henriques <lhenriques@suse.com> Reviewed-by: "Yan, Zheng" <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ceph: try getting buffer capability for readahead/fadviseYan, Zheng2017-05-084-11/+73
| | | | | | | | | | | | | commit 2b1ac852eb67a6e95595e576371d23519105559f upstream. For readahead/fadvise cases, caller of ceph_readpages does not hold buffer capability. Pages can be added to page cache while there is no buffer capability. This can cause data integrity issue. Signed-off-by: Yan, Zheng <zyan@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ceph: fix recursion between ceph_set_acl() and __ceph_setattr()Yan, Zheng2017-05-031-12/+10
| | | | | | | | | | | | | | | | | | | | | | | | commit 8179a101eb5f4ef0ac9a915fcea9a9d3109efa90 upstream. ceph_set_acl() calls __ceph_setattr() if the setacl operation needs to modify inode's i_mode. __ceph_setattr() updates inode's i_mode, then calls posix_acl_chmod(). The problem is that __ceph_setattr() calls posix_acl_chmod() before sending the setattr request. The get_acl() call in posix_acl_chmod() can trigger a getxattr request. The reply of the getxattr request can restore inode's i_mode to its old value. The set_acl() call in posix_acl_chmod() sees old value of inode's i_mode, so it calls __ceph_setattr() again. Link: http://tracker.ceph.com/issues/19688 Reported-by: Jerry Lee <leisurelysw24@gmail.com> Signed-off-by: "Yan, Zheng" <zyan@redhat.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Tested-by: Luis Henriques <lhenriques@suse.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ceph: remove req from unsafe list when unregistering itJeff Layton2017-03-151-2/+3
| | | | | | | | | | | | | | commit df963ea8a082d31521a120e8e31a29ad8a1dc215 upstream. There's no reason a request should ever be on a s_unsafe list but not in the request tree. Link: http://tracker.ceph.com/issues/18474 Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Yan, Zheng <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ceph: update readpages osd request according to size of pagesYan, Zheng2017-03-121-0/+1
| | | | | | | | | | | | | commit d641df819db8b80198fd85d9de91137e8a823b07 upstream. add_to_page_cache_lru() can fails, so the actual pages to read can be smaller than the initial size of osd request. We need to update osd request size in that case. Signed-off-by: Yan, Zheng <zyan@redhat.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ceph: fix endianness bug in frag_tree_split_cmpJeff Layton2017-01-261-1/+2
| | | | | | | | | | | | | | | | | | | | | | | commit fe2ed42517533068ac03eed5630fffafff27eacf upstream. sparse says: fs/ceph/inode.c:308:36: warning: incorrect type in argument 1 (different base types) fs/ceph/inode.c:308:36: expected unsigned int [unsigned] [usertype] a fs/ceph/inode.c:308:36: got restricted __le32 [usertype] frag fs/ceph/inode.c:308:46: warning: incorrect type in argument 2 (different base types) fs/ceph/inode.c:308:46: expected unsigned int [unsigned] [usertype] b fs/ceph/inode.c:308:46: got restricted __le32 [usertype] frag We need to convert these values to host-endian before calling the comparator. Fixes: a407846ef7c6 ("ceph: don't assume frag tree splits in mds reply are sorted") Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Sage Weil <sage@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ceph: fix endianness of getattr mask in ceph_d_revalidateJeff Layton2017-01-261-2/+3
| | | | | | | | | | | | | | | | | commit 1097680d759918ce4a8705381c0ab2ed7bd60cf1 upstream. sparse says: fs/ceph/dir.c:1248:50: warning: incorrect type in assignment (different base types) fs/ceph/dir.c:1248:50: expected restricted __le32 [usertype] mask fs/ceph/dir.c:1248:50: got int [signed] [assigned] mask Fixes: 200fd27c8fa2 ("ceph: use lookup request to revalidate dentry") Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Sage Weil <sage@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ceph: fix ceph_get_caps() interruptionYan, Zheng2017-01-261-1/+6
| | | | | | | | | | | | commit 6e09d0fb64402cec579f029ca4c7f39f5c48fc60 upstream. Commit 5c341ee32881 ("ceph: fix scheduler warning due to nested blocking") causes infinite loop when process is interrupted. Fix it. Signed-off-by: Yan, Zheng <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ceph: fix scheduler warning due to nested blockingNikolay Borisov2017-01-261-3/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 5c341ee32881c554727ec14b71ec3e8832f01989 upstream. try_get_cap_refs can be used as a condition in a wait_event* calls. This is all fine until it has to call __ceph_do_pending_vmtruncate, which in turn acquires the i_truncate_mutex. This leads to a situation in which a task's state is !TASK_RUNNING and at the same time it's trying to acquire a sleeping primitive. In essence a nested sleeping primitives are being used. This causes the following warning: WARNING: CPU: 22 PID: 11064 at kernel/sched/core.c:7631 __might_sleep+0x9f/0xb0() do not call blocking ops when !TASK_RUNNING; state=1 set at [<ffffffff8109447d>] prepare_to_wait_event+0x5d/0x110 ipmi_msghandler tcp_scalable ib_qib dca ib_mad ib_core ib_addr ipv6 CPU: 22 PID: 11064 Comm: fs_checker.pl Tainted: G O 4.4.20-clouder2 #6 Hardware name: Supermicro X10DRi/X10DRi, BIOS 1.1a 10/16/2015 0000000000000000 ffff8838b416fa88 ffffffff812f4409 ffff8838b416fad0 ffffffff81a034f2 ffff8838b416fac0 ffffffff81052b46 ffffffff81a0432c 0000000000000061 0000000000000000 0000000000000000 ffff88167bda54a0 Call Trace: [<ffffffff812f4409>] dump_stack+0x67/0x9e [<ffffffff81052b46>] warn_slowpath_common+0x86/0xc0 [<ffffffff81052bcc>] warn_slowpath_fmt+0x4c/0x50 [<ffffffff8109447d>] ? prepare_to_wait_event+0x5d/0x110 [<ffffffff8109447d>] ? prepare_to_wait_event+0x5d/0x110 [<ffffffff8107767f>] __might_sleep+0x9f/0xb0 [<ffffffff81612d30>] mutex_lock+0x20/0x40 [<ffffffffa04eea14>] __ceph_do_pending_vmtruncate+0x44/0x1a0 [ceph] [<ffffffffa04fa692>] try_get_cap_refs+0xa2/0x320 [ceph] [<ffffffffa04fd6f5>] ceph_get_caps+0x255/0x2b0 [ceph] [<ffffffff81094370>] ? wait_woken+0xb0/0xb0 [<ffffffffa04f2c11>] ceph_write_iter+0x2b1/0xde0 [ceph] [<ffffffff81613f22>] ? schedule_timeout+0x202/0x260 [<ffffffff8117f01a>] ? kmem_cache_free+0x1ea/0x200 [<ffffffff811b46ce>] ? iput+0x9e/0x230 [<ffffffff81077632>] ? __might_sleep+0x52/0xb0 [<ffffffff81156147>] ? __might_fault+0x37/0x40 [<ffffffff8119e123>] ? cp_new_stat+0x153/0x170 [<ffffffff81198cfa>] __vfs_write+0xaa/0xe0 [<ffffffff81199369>] vfs_write+0xa9/0x190 [<ffffffff811b6d01>] ? set_close_on_exec+0x31/0x70 [<ffffffff8119a056>] SyS_write+0x46/0xa0 This happens since wait_event_interruptible can interfere with the mutex locking code, since they both fiddle with the task state. Fix the issue by using the newly-added nested blocking infrastructure in 61ada528dea0 ("sched/wait: Provide infrastructure to deal with nested blocking") Link: https://lwn.net/Articles/628628/ Signed-off-by: Nikolay Borisov <kernel@kyup.com> Signed-off-by: Yan, Zheng <zyan@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>