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2020-08-26do_epoll_ctl(): clean the failure exits up a bitAl Viro1-6/+4
commit 52c479697c9b73f628140dcdfcd39ea302d05482 upstream. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26epoll: Keep a reference on files added to the check listMarc Zyngier1-2/+7
commit a9ed4a6560b8562b7e2e2bed9527e88001f7b682 upstream. When adding a new fd to an epoll, and that this new fd is an epoll fd itself, we recursively scan the fds attached to it to detect cycles, and add non-epool files to a "check list" that gets subsequently parsed. However, this check list isn't completely safe when deletions can happen concurrently. To sidestep the issue, make sure that a struct file placed on the check list sees its f_count increased, ensuring that a concurrent deletion won't result in the file disapearing from under our feet. Cc: stable@vger.kernel.org Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26afs: Fix NULL deref in afs_dynroot_depopulate()David Howells1-9/+11
[ Upstream commit 5e0b17b026eb7c6de9baa9b0d45a51b05f05abe1 ] If an error occurs during the construction of an afs superblock, it's possible that an error occurs after a superblock is created, but before we've created the root dentry. If the superblock has a dynamic root (ie. what's normally mounted on /afs), the afs_kill_super() will call afs_dynroot_depopulate() to unpin any created dentries - but this will oops if the root hasn't been created yet. Fix this by skipping that bit of code if there is no root dentry. This leads to an oops looking like: general protection fault, ... KASAN: null-ptr-deref in range [0x0000000000000068-0x000000000000006f] ... RIP: 0010:afs_dynroot_depopulate+0x25f/0x529 fs/afs/dynroot.c:385 ... Call Trace: afs_kill_super+0x13b/0x180 fs/afs/super.c:535 deactivate_locked_super+0x94/0x160 fs/super.c:335 afs_get_tree+0x1124/0x1460 fs/afs/super.c:598 vfs_get_tree+0x89/0x2f0 fs/super.c:1547 do_new_mount fs/namespace.c:2875 [inline] path_mount+0x1387/0x2070 fs/namespace.c:3192 do_mount fs/namespace.c:3205 [inline] __do_sys_mount fs/namespace.c:3413 [inline] __se_sys_mount fs/namespace.c:3390 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3390 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 which is oopsing on this line: inode_lock(root->d_inode); presumably because sb->s_root was NULL. Fixes: 0da0b7fd73e4 ("afs: Display manually added cells in dynamic root mount") Reported-by: syzbot+c1eff8205244ae7e11a6@syzkaller.appspotmail.com Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-26ext4: don't allow overlapping system zonesJan Kara1-23/+13
[ Upstream commit bf9a379d0980e7413d94cb18dac73db2bfc5f470 ] Currently, add_system_zone() just silently merges two added system zones that overlap. However the overlap should not happen and it generally suggests that some unrelated metadata overlap which indicates the fs is corrupted. We should have caught such problems earlier (e.g. in ext4_check_descriptors()) but add this check as another line of defense. In later patch we also use this for stricter checking of journal inode extent tree. Reviewed-by: Lukas Czerner <lczerner@redhat.com> Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20200728130437.7804-3-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-26ext4: fix potential negative array index in do_split()Eric Sandeen1-3/+13
[ Upstream commit 5872331b3d91820e14716632ebb56b1399b34fe1 ] If for any reason a directory passed to do_split() does not have enough active entries to exceed half the size of the block, we can end up iterating over all "count" entries without finding a split point. In this case, count == move, and split will be zero, and we will attempt a negative index into map[]. Guard against this by detecting this case, and falling back to split-to-half-of-count instead; in this case we will still have plenty of space (> half blocksize) in each split block. Fixes: ef2b02d3e617 ("ext34: ensure do_split leaves enough free space in both blocks") Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Andreas Dilger <adilger@dilger.ca> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/f53e246b-647c-64bb-16ec-135383c70ad7@redhat.com Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-26fs/signalfd.c: fix inconsistent return codes for signalfd4Helge Deller1-4/+6
[ Upstream commit a089e3fd5a82aea20f3d9ec4caa5f4c65cc2cfcc ] The kernel signalfd4() syscall returns different error codes when called either in compat or native mode. This behaviour makes correct emulation in qemu and testing programs like LTP more complicated. Fix the code to always return -in both modes- EFAULT for unaccessible user memory, and EINVAL when called with an invalid signal mask. Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Laurent Vivier <laurent@vivier.eu> Link: http://lkml.kernel.org/r/20200530100707.GA10159@ls3530.fritz.box Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-26xfs: Fix UBSAN null-ptr-deref in xfs_sysfs_initEiichi Tsukata1-2/+4
[ Upstream commit 96cf2a2c75567ff56195fe3126d497a2e7e4379f ] If xfs_sysfs_init is called with parent_kobj == NULL, UBSAN shows the following warning: UBSAN: null-ptr-deref in ./fs/xfs/xfs_sysfs.h:37:23 member access within null pointer of type 'struct xfs_kobj' Call Trace: dump_stack+0x10e/0x195 ubsan_type_mismatch_common+0x241/0x280 __ubsan_handle_type_mismatch_v1+0x32/0x40 init_xfs_fs+0x12b/0x28f do_one_initcall+0xdd/0x1d0 do_initcall_level+0x151/0x1b6 do_initcalls+0x50/0x8f do_basic_setup+0x29/0x2b kernel_init_freeable+0x19f/0x20b kernel_init+0x11/0x1e0 ret_from_fork+0x22/0x30 Fix it by checking parent_kobj before the code accesses its member. Signed-off-by: Eiichi Tsukata <devel@etsukata.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> [darrick: minor whitespace edits] Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-26ceph: fix use-after-free for fsc->mdscXiubo Li1-1/+2
[ Upstream commit a7caa88f8b72c136f9a401f498471b8a8e35370d ] If the ceph_mdsc_init() fails, it will free the mdsc already. Reported-by: syzbot+b57f46d8d6ea51960b8c@syzkaller.appspotmail.com 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>
2020-08-26jffs2: fix UAF problemZhe Li1-1/+5
[ Upstream commit 798b7347e4f29553db4b996393caf12f5b233daf ] The log of UAF problem is listed below. BUG: KASAN: use-after-free in jffs2_rmdir+0xa4/0x1cc [jffs2] at addr c1f165fc Read of size 4 by task rm/8283 ============================================================================= BUG kmalloc-32 (Tainted: P B O ): kasan: bad access detected ----------------------------------------------------------------------------- INFO: Allocated in 0xbbbbbbbb age=3054364 cpu=0 pid=0 0xb0bba6ef jffs2_write_dirent+0x11c/0x9c8 [jffs2] __slab_alloc.isra.21.constprop.25+0x2c/0x44 __kmalloc+0x1dc/0x370 jffs2_write_dirent+0x11c/0x9c8 [jffs2] jffs2_do_unlink+0x328/0x5fc [jffs2] jffs2_rmdir+0x110/0x1cc [jffs2] vfs_rmdir+0x180/0x268 do_rmdir+0x2cc/0x300 ret_from_syscall+0x0/0x3c INFO: Freed in 0x205b age=3054364 cpu=0 pid=0 0x2e9173 jffs2_add_fd_to_list+0x138/0x1dc [jffs2] jffs2_add_fd_to_list+0x138/0x1dc [jffs2] jffs2_garbage_collect_dirent.isra.3+0x21c/0x288 [jffs2] jffs2_garbage_collect_live+0x16bc/0x1800 [jffs2] jffs2_garbage_collect_pass+0x678/0x11d4 [jffs2] jffs2_garbage_collect_thread+0x1e8/0x3b0 [jffs2] kthread+0x1a8/0x1b0 ret_from_kernel_thread+0x5c/0x64 Call Trace: [c17ddd20] [c02452d4] kasan_report.part.0+0x298/0x72c (unreliable) [c17ddda0] [d2509680] jffs2_rmdir+0xa4/0x1cc [jffs2] [c17dddd0] [c026da04] vfs_rmdir+0x180/0x268 [c17dde00] [c026f4e4] do_rmdir+0x2cc/0x300 [c17ddf40] [c001a658] ret_from_syscall+0x0/0x3c The root cause is that we don't get "jffs2_inode_info.sem" before we scan list "jffs2_inode_info.dents" in function jffs2_rmdir. This patch add codes to get "jffs2_inode_info.sem" before we scan "jffs2_inode_info.dents" to slove the UAF problem. Signed-off-by: Zhe Li <lizhe67@huawei.com> Reviewed-by: Hou Tao <houtao1@huawei.com> Signed-off-by: Richard Weinberger <richard@nod.at> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-26xfs: fix inode quota reservation checksDarrick J. Wong1-1/+1
[ Upstream commit f959b5d037e71a4d69b5bf71faffa065d9269b4a ] xfs_trans_dqresv is the function that we use to make reservations against resource quotas. Each resource contains two counters: the q_core counter, which tracks resources allocated on disk; and the dquot reservation counter, which tracks how much of that resource has either been allocated or reserved by threads that are working on metadata updates. For disk blocks, we compare the proposed reservation counter against the hard and soft limits to decide if we're going to fail the operation. However, for inodes we inexplicably compare against the q_core counter, not the incore reservation count. Since the q_core counter is always lower than the reservation count and we unlock the dquot between reservation and transaction commit, this means that multiple threads can reserve the last inode count before we hit the hard limit, and when they commit, we'll be well over the hard limit. Fix this by checking against the incore inode reservation counter, since we would appear to maintain that correctly (and that's what we report in GETQUOTA). Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Allison Collins <allison.henderson@oracle.com> Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-26jbd2: add the missing unlock_buffer() in the error path of ↵zhangyi (F)1-1/+3
jbd2_write_superblock() commit ef3f5830b859604eda8723c26d90ab23edc027a4 upstream. jbd2_write_superblock() is under the buffer lock of journal superblock before ending that superblock write, so add a missing unlock_buffer() in in the error path before submitting buffer. Fixes: 742b06b5628f ("jbd2: check superblock mapped prior to committing") Signed-off-by: zhangyi (F) <yi.zhang@huawei.com> Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com> Cc: stable@kernel.org Link: https://lore.kernel.org/r/20200620061948.2049579-1-yi.zhang@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26ext4: fix checking of directory entry validity for inline directoriesJan Kara1-3/+3
commit 7303cb5bfe845f7d43cd9b2dbd37dbb266efda9b upstream. ext4_search_dir() and ext4_generic_delete_entry() can be called both for standard director blocks and for inline directories stored inside inode or inline xattr space. For the second case we didn't call ext4_check_dir_entry() with proper constraints that could result in accepting corrupted directory entry as well as false positive filesystem errors like: EXT4-fs error (device dm-0): ext4_search_dir:1395: inode #28320400: block 113246792: comm dockerd: bad entry in directory: directory entry too close to block end - offset=0, inode=28320403, rec_len=32, name_len=8, size=4096 Fix the arguments passed to ext4_check_dir_entry(). Fixes: 109ba779d6cc ("ext4: check for directory entries too close to block end") CC: stable@vger.kernel.org Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20200731162135.8080-1-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26romfs: fix uninitialized memory leak in romfs_dev_read()Jann Horn1-3/+1
commit bcf85fcedfdd17911982a3e3564fcfec7b01eebd upstream. romfs has a superblock field that limits the size of the filesystem; data beyond that limit is never accessed. romfs_dev_read() fetches a caller-supplied number of bytes from the backing device. It returns 0 on success or an error code on failure; therefore, its API can't represent short reads, it's all-or-nothing. However, when romfs_dev_read() detects that the requested operation would cross the filesystem size limit, it currently silently truncates the requested number of bytes. This e.g. means that when the content of a file with size 0x1000 starts one byte before the filesystem size limit, ->readpage() will only fill a single byte of the supplied page while leaving the rest uninitialized, leaking that uninitialized memory to userspace. Fix it by returning an error code instead of truncating the read when the requested read operation would go beyond the end of the filesystem. Fixes: da4458bda237 ("NOMMU: Make it possible for RomFS to use MTD devices directly") Signed-off-by: Jann Horn <jannh@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: David Howells <dhowells@redhat.com> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20200818013202.2246365-1-jannh@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26btrfs: add wrapper for transaction abort predicateDavid Sterba6-20/+33
[ Upstream commit bf31f87f71cc7a89871ab0a451c047a0c0144bf1 ] The status of aborted transaction can change between calls and it needs to be accessed by READ_ONCE. Add a helper that also wraps the unlikely hint. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-26btrfs: return EROFS for BTRFS_FS_STATE_ERROR casesJosef Bacik3-3/+6
Eric reported seeing this message while running generic/475 BTRFS: error (device dm-3) in btrfs_sync_log:3084: errno=-117 Filesystem corrupted Full stack trace: BTRFS: error (device dm-0) in btrfs_commit_transaction:2323: errno=-5 IO failure (Error while writing out transaction) BTRFS info (device dm-0): forced readonly BTRFS warning (device dm-0): Skipping commit of aborted transaction. ------------[ cut here ]------------ BTRFS: error (device dm-0) in cleanup_transaction:1894: errno=-5 IO failure BTRFS: Transaction aborted (error -117) BTRFS warning (device dm-0): direct IO failed ino 3555 rw 0,0 sector 0x1c6480 len 4096 err no 10 BTRFS warning (device dm-0): direct IO failed ino 3555 rw 0,0 sector 0x1c6488 len 4096 err no 10 BTRFS warning (device dm-0): direct IO failed ino 3555 rw 0,0 sector 0x1c6490 len 4096 err no 10 BTRFS warning (device dm-0): direct IO failed ino 3555 rw 0,0 sector 0x1c6498 len 4096 err no 10 BTRFS warning (device dm-0): direct IO failed ino 3555 rw 0,0 sector 0x1c64a0 len 4096 err no 10 BTRFS warning (device dm-0): direct IO failed ino 3555 rw 0,0 sector 0x1c64a8 len 4096 err no 10 BTRFS warning (device dm-0): direct IO failed ino 3555 rw 0,0 sector 0x1c64b0 len 4096 err no 10 BTRFS warning (device dm-0): direct IO failed ino 3555 rw 0,0 sector 0x1c64b8 len 4096 err no 10 BTRFS warning (device dm-0): direct IO failed ino 3555 rw 0,0 sector 0x1c64c0 len 4096 err no 10 BTRFS warning (device dm-0): direct IO failed ino 3572 rw 0,0 sector 0x1b85e8 len 4096 err no 10 BTRFS warning (device dm-0): direct IO failed ino 3572 rw 0,0 sector 0x1b85f0 len 4096 err no 10 WARNING: CPU: 3 PID: 23985 at fs/btrfs/tree-log.c:3084 btrfs_sync_log+0xbc8/0xd60 [btrfs] BTRFS warning (device dm-0): direct IO failed ino 3548 rw 0,0 sector 0x1d4288 len 4096 err no 10 BTRFS warning (device dm-0): direct IO failed ino 3548 rw 0,0 sector 0x1d4290 len 4096 err no 10 BTRFS warning (device dm-0): direct IO failed ino 3548 rw 0,0 sector 0x1d4298 len 4096 err no 10 BTRFS warning (device dm-0): direct IO failed ino 3548 rw 0,0 sector 0x1d42a0 len 4096 err no 10 BTRFS warning (device dm-0): direct IO failed ino 3548 rw 0,0 sector 0x1d42a8 len 4096 err no 10 BTRFS warning (device dm-0): direct IO failed ino 3548 rw 0,0 sector 0x1d42b0 len 4096 err no 10 BTRFS warning (device dm-0): direct IO failed ino 3548 rw 0,0 sector 0x1d42b8 len 4096 err no 10 BTRFS warning (device dm-0): direct IO failed ino 3548 rw 0,0 sector 0x1d42c0 len 4096 err no 10 BTRFS warning (device dm-0): direct IO failed ino 3548 rw 0,0 sector 0x1d42c8 len 4096 err no 10 BTRFS warning (device dm-0): direct IO failed ino 3548 rw 0,0 sector 0x1d42d0 len 4096 err no 10 CPU: 3 PID: 23985 Comm: fsstress Tainted: G W L 5.8.0-rc4-default+ #1181 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba527-rebuilt.opensuse.org 04/01/2014 RIP: 0010:btrfs_sync_log+0xbc8/0xd60 [btrfs] RSP: 0018:ffff909a44d17bd0 EFLAGS: 00010286 RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000001 RDX: ffff8f3be41cb940 RSI: ffffffffb0108d2b RDI: ffffffffb0108ff7 RBP: ffff909a44d17e70 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000037988 R12: ffff8f3bd20e4000 R13: ffff8f3bd20e4428 R14: 00000000ffffff8b R15: ffff909a44d17c70 FS: 00007f6a6ed3fb80(0000) GS:ffff8f3c3dc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6a6ed3e000 CR3: 00000000525c0003 CR4: 0000000000160ee0 Call Trace: ? finish_wait+0x90/0x90 ? __mutex_unlock_slowpath+0x45/0x2a0 ? lock_acquire+0xa3/0x440 ? lockref_put_or_lock+0x9/0x30 ? dput+0x20/0x4a0 ? dput+0x20/0x4a0 ? do_raw_spin_unlock+0x4b/0xc0 ? _raw_spin_unlock+0x1f/0x30 btrfs_sync_file+0x335/0x490 [btrfs] do_fsync+0x38/0x70 __x64_sys_fsync+0x10/0x20 do_syscall_64+0x50/0xe0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f6a6ef1b6e3 Code: Bad RIP value. RSP: 002b:00007ffd01e20038 EFLAGS: 00000246 ORIG_RAX: 000000000000004a RAX: ffffffffffffffda RBX: 000000000007a120 RCX: 00007f6a6ef1b6e3 RDX: 00007ffd01e1ffa0 RSI: 00007ffd01e1ffa0 RDI: 0000000000000003 RBP: 0000000000000003 R08: 0000000000000001 R09: 00007ffd01e2004c R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000009f R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 irq event stamp: 0 hardirqs last enabled at (0): [<0000000000000000>] 0x0 hardirqs last disabled at (0): [<ffffffffb007fe0b>] copy_process+0x67b/0x1b00 softirqs last enabled at (0): [<ffffffffb007fe0b>] copy_process+0x67b/0x1b00 softirqs last disabled at (0): [<0000000000000000>] 0x0 ---[ end trace af146e0e38433456 ]--- BTRFS: error (device dm-0) in btrfs_sync_log:3084: errno=-117 Filesystem corrupted This ret came from btrfs_write_marked_extents(). If we get an aborted transaction via EIO before, we'll see it in btree_write_cache_pages() and return EUCLEAN, which gets printed as "Filesystem corrupted". Except we shouldn't be returning EUCLEAN here, we need to be returning EROFS because EUCLEAN is reserved for actual corruption, not IO errors. We are inconsistent about our handling of BTRFS_FS_STATE_ERROR elsewhere, but we want to use EROFS for this particular case. The original transaction abort has the real error code for why we ended up with an aborted transaction, all subsequent actions just need to return EROFS because they may not have a trans handle and have no idea about the original cause of the abort. After patch "btrfs: don't WARN if we abort a transaction with EROFS" the stacktrace will not be dumped either. Reported-by: Eric Sandeen <esandeen@redhat.com> CC: stable@vger.kernel.org # 5.4+ Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> [ add full test stacktrace ] Signed-off-by: David Sterba <dsterba@suse.com>
2020-08-26btrfs: don't show full path of bind mounts in subvol=Josef Bacik1-2/+8
[ Upstream commit 3ef3959b29c4a5bd65526ab310a1a18ae533172a ] Chris Murphy reported a problem where rpm ostree will bind mount a bunch of things for whatever voodoo it's doing. But when it does this /proc/mounts shows something like /dev/sda /mnt/test btrfs rw,relatime,subvolid=256,subvol=/foo 0 0 /dev/sda /mnt/test/baz btrfs rw,relatime,subvolid=256,subvol=/foo/bar 0 0 Despite subvolid=256 being subvol=/foo. This is because we're just spitting out the dentry of the mount point, which in the case of bind mounts is the source path for the mountpoint. Instead we should spit out the path to the actual subvol. Fix this by looking up the name for the subvolid we have mounted. With this fix the same test looks like this /dev/sda /mnt/test btrfs rw,relatime,subvolid=256,subvol=/foo 0 0 /dev/sda /mnt/test/baz btrfs rw,relatime,subvolid=256,subvol=/foo 0 0 Reported-by: Chris Murphy <chris@colorremedies.com> CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-26btrfs: export helpers for subvolume name/id resolutionMarcos Paulo de Souza4-8/+15
[ Upstream commit c0c907a47dccf2cf26251a8fb4a8e7a3bf79ce84 ] The functions will be used outside of export.c and super.c to allow resolving subvolume name from a given id, eg. for subvolume deletion by id ioctl. Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> [ split from the next patch ] Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-26gfs2: Never call gfs2_block_zero_range with an open transactionBob Peterson1-30/+39
[ Upstream commit 70499cdfeb3625c87eebe4f7a7ea06fa7447e5df ] Before this patch, some functions started transactions then they called gfs2_block_zero_range. However, gfs2_block_zero_range, like writes, can start transactions, which results in a recursive transaction error. For example: do_shrink trunc_start gfs2_trans_begin <------------------------------------------------ gfs2_block_zero_range iomap_zero_range(inode, from, length, NULL, &gfs2_iomap_ops); iomap_apply ... iomap_zero_range_actor iomap_begin gfs2_iomap_begin gfs2_iomap_begin_write actor (iomap_zero_range_actor) iomap_zero iomap_write_begin gfs2_iomap_page_prepare gfs2_trans_begin <------------------------ This patch reorders the callers of gfs2_block_zero_range so that they only start their transactions after the call. It also adds a BUG_ON to ensure this doesn't happen again. Fixes: 2257e468a63b ("gfs2: implement gfs2_block_zero_range using iomap_zero_range") Cc: stable@vger.kernel.org # v5.5+ Signed-off-by: Bob Peterson <rpeterso@redhat.com> Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-26gfs2: Improve mmap write vs. punch_hole consistencyAndreas Gruenbacher1-2/+9
[ Upstream commit 39c3a948ecf6e7b8f55f0e91a5febc924fede4d7 ] When punching a hole in a file, use filemap_write_and_wait_range to write back any dirty pages in the range of the hole. As a side effect, if the hole isn't page aligned, this marks unaligned pages at the beginning and the end of the hole read-only. This is required when the block size is smaller than the page size: when those pages are written to again after the hole punching, we must make sure that page_mkwrite is called for those pages so that the page will be fully allocated and any blocks turned into holes from the hole punching will be reallocated. (If a page is writably mapped, page_mkwrite won't be called.) Fixes xfstest generic/567. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-21fs/ufs: avoid potential u32 multiplication overflowColin Ian King1-1/+1
[ Upstream commit 88b2e9b06381551b707d980627ad0591191f7a2d ] The 64 bit ino is being compared to the product of two u32 values, however, the multiplication is being performed using a 32 bit multiply so there is a potential of an overflow. To be fully safe, cast uspi->s_ncg to a u64 to ensure a 64 bit multiplication occurs to avoid any chance of overflow. Fixes: f3e2a520f5fb ("ufs: NFS support") Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Evgeniy Dushistov <dushistov@mail.ru> Cc: Alexey Dobriyan <adobriyan@gmail.com> Link: http://lkml.kernel.org/r/20200715170355.1081713-1-colin.king@canonical.com Addresses-Coverity: ("Unintentional integer overflow") Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-21fs/minix: remove expected error message in block_to_path()Eric Biggers2-12/+12
[ Upstream commit f666f9fb9a36f1c833b9d18923572f0e4d304754 ] When truncating a file to a size within the last allowed logical block, block_to_path() is called with the *next* block. This exceeds the limit, causing the "block %ld too big" error message to be printed. This case isn't actually an error; there are just no more blocks past that point. So, remove this error message. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Qiujun Huang <anenbupt@gmail.com> Link: http://lkml.kernel.org/r/20200628060846.682158-7-ebiggers@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-21fs/minix: fix block limit check for V1 filesystemsEric Biggers1-1/+1
[ Upstream commit 0a12c4a8069607247cb8edc3b035a664e636fd9a ] The minix filesystem reads its maximum file size from its on-disk superblock. This value isn't necessarily a multiple of the block size. When it's not, the V1 block mapping code doesn't allow mapping the last possible block. Commit 6ed6a722f9ab ("minixfs: fix block limit check") fixed this in the V2 mapping code. Fix it in the V1 mapping code too. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Qiujun Huang <anenbupt@gmail.com> Link: http://lkml.kernel.org/r/20200628060846.682158-6-ebiggers@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-21fs/minix: set s_maxbytes correctlyEric Biggers4-9/+9
[ Upstream commit 32ac86efff91a3e4ef8c3d1cadd4559e23c8e73a ] The minix filesystem leaves super_block::s_maxbytes at MAX_NON_LFS rather than setting it to the actual filesystem-specific limit. This is broken because it means userspace doesn't see the standard behavior like getting EFBIG and SIGXFSZ when exceeding the maximum file size. Fix this by setting s_maxbytes correctly. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Qiujun Huang <anenbupt@gmail.com> Link: http://lkml.kernel.org/r/20200628060846.682158-5-ebiggers@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-21nfs: Fix getxattr kernel panic and memory overflowJeffrey Mitchell2-3/+5
[ Upstream commit b4487b93545214a9db8cbf32e86411677b0cca21 ] Move the buffer size check to decode_attr_security_label() before memcpy() Only call memcpy() if the buffer is large enough Fixes: aa9c2669626c ("NFS: Client implementation of Labeled-NFS") Signed-off-by: Jeffrey Mitchell <jeffrey.mitchell@starlab.io> [Trond: clean up duplicate test of label->len != 0] Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-21nfs: nfs_file_write() should check for writeback errorsScott Mayhew1-3/+9
[ Upstream commit ce368536dd614452407dc31e2449eb84681a06af ] The NFS_CONTEXT_ERROR_WRITE flag (as well as the check of said flag) was removed by commit 6fbda89b257f. The absence of an error check allows writes to be continually queued up for a server that may no longer be able to handle them. Fix it by adding an error check using the generic error reporting functions. Fixes: 6fbda89b257f ("NFS: Replace custom error reporting mechanism with generic one") Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-21ubifs: Fix wrong orphan node deletion in ubifs_jnl_update|renameZhihao Cheng1-4/+6
[ Upstream commit 094b6d1295474f338201b846a1f15e72eb0b12cf ] There a wrong orphan node deleting in error handling path in ubifs_jnl_update() and ubifs_jnl_rename(), which may cause following error msg: UBIFS error (ubi0:0 pid 1522): ubifs_delete_orphan [ubifs]: missing orphan ino 65 Fix this by checking whether the node has been operated for adding to orphan list before being deleted, Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com> Fixes: 823838a486888cf484e ("ubifs: Add hashes to the tree node cache") Signed-off-by: Richard Weinberger <richard@nod.at> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-21nfs: ensure correct writeback errors are returned on close()Scott Mayhew2-2/+8
[ Upstream commit 67dd23f9e6fbaf163431912ef5599c5e0693476c ] nfs_wb_all() calls filemap_write_and_wait(), which uses filemap_check_errors() to determine the error to return. filemap_check_errors() only looks at the mapping->flags and will therefore only return either -ENOSPC or -EIO. To ensure that the correct error is returned on close(), nfs{,4}_file_flush() should call filemap_check_wb_err() which looks at the errseq value in mapping->wb_err without consuming it. Fixes: 6fbda89b257f ("NFS: Replace custom error reporting mechanism with generic one") Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-21orangefs: get rid of knob code...Mike Marshall3-62/+7
commit ec95f1dedc9c64ac5a8b0bdb7c276936c70fdedd upstream. Christoph Hellwig sent in a reversion of "orangefs: remember count when reading." because: ->read_iter calls can race with each other and one or more ->flush calls. Remove the the scheme to store the read count in the file private data as is is completely racy and can cause use after free or double free conditions Christoph's reversion caused Orangefs not to work or to compile. I added a patch that fixed that, but intel's kbuild test robot pointed out that sending Christoph's patch followed by my patch upstream, it would break bisection because of the failure to compile. So I have combined the reversion plus my patch... here's the commit message that was in my patch: Logically, optimal Orangefs "pages" are 4 megabytes. Reading large Orangefs files 4096 bytes at a time is like trying to kick a dead whale down the beach. Before Christoph's "Revert orangefs: remember count when reading." I tried to give users a knob whereby they could, for example, use "count" in read(2) or bs with dd(1) to get whatever they considered an appropriate amount of bytes at a time from Orangefs and fill as many page cache pages as they could at once. Without the racy code that Christoph reverted Orangefs won't even compile, much less work. So this replaces the logic that used the private file data that Christoph reverted with a static number of bytes to read from Orangefs. I ran tests like the following to determine what a reasonable static number of bytes might be: dd if=/pvfsmnt/asdf of=/dev/null count=128 bs=4194304 dd if=/pvfsmnt/asdf of=/dev/null count=256 bs=2097152 dd if=/pvfsmnt/asdf of=/dev/null count=512 bs=1048576 . . . dd if=/pvfsmnt/asdf of=/dev/null count=4194304 bs=128 Reads seem faster using the static number, so my "knob code" wasn't just racy, it wasn't even a good idea... Signed-off-by: Mike Marshall <hubcap@omnibond.com> Reported-by: kbuild test robot <lkp@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21ceph: handle zero-length feature mask in session messagesJeff Layton1-2/+4
commit 02e37571f9e79022498fd0525c073b07e9d9ac69 upstream. Most session messages contain a feature mask, but the MDS will routinely send a REJECT message with one that is zero-length. Commit 0fa8263367db ("ceph: fix endianness bug when handling MDS session feature bits") fixed the decoding of the feature mask, but failed to account for the MDS sending a zero-length feature mask. This causes REJECT message decoding to fail. Skip trying to decode a feature mask if the word count is zero. Cc: stable@vger.kernel.org URL: https://tracker.ceph.com/issues/46823 Fixes: 0fa8263367db ("ceph: fix endianness bug when handling MDS session feature bits") Signed-off-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Ilya Dryomov <idryomov@gmail.com> Tested-by: Patrick Donnelly <pdonnell@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21ceph: set sec_context xattr on symlink creationJeff Layton1-0/+4
commit b748fc7a8763a5b3f8149f12c45711cd73ef8176 upstream. Symlink inodes should have the security context set in their xattrs on creation. We already set the context on creation, but we don't attach the pagelist. The effect is that symlink inodes don't get an SELinux context set on them at creation, so they end up unlabeled instead of inheriting the proper context. Make it do so. Cc: stable@vger.kernel.org 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21ocfs2: change slot number type s16 to u16Junxiao Bi3-6/+6
commit 38d51b2dd171ad973afc1f5faab825ed05a2d5e9 upstream. Dan Carpenter reported the following static checker warning. fs/ocfs2/super.c:1269 ocfs2_parse_options() warn: '(-1)' 65535 can't fit into 32767 'mopt->slot' fs/ocfs2/suballoc.c:859 ocfs2_init_inode_steal_slot() warn: '(-1)' 65535 can't fit into 32767 'osb->s_inode_steal_slot' fs/ocfs2/suballoc.c:867 ocfs2_init_meta_steal_slot() warn: '(-1)' 65535 can't fit into 32767 'osb->s_meta_steal_slot' That's because OCFS2_INVALID_SLOT is (u16)-1. Slot number in ocfs2 can be never negative, so change s16 to u16. Fixes: 9277f8334ffc ("ocfs2: fix value of OCFS2_INVALID_SLOT") Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com> Reviewed-by: Gang He <ghe@suse.com> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: Jun Piao <piaojun@huawei.com> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20200627001259.19757-1-junxiao.bi@oracle.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21ext2: fix missing percpu_counter_incMikulas Patocka1-1/+2
commit bc2fbaa4d3808aef82dd1064a8e61c16549fe956 upstream. sbi->s_freeinodes_counter is only decreased by the ext2 code, it is never increased. This patch fixes it. Note that sbi->s_freeinodes_counter is only used in the algorithm that tries to find the group for new allocations, so this bug is not easily visible (the only visibility is that the group finding algorithm selects inoptinal result). Link: https://lore.kernel.org/r/alpine.LRH.2.02.2004201538300.19436@file01.intranet.prod.int.rdu2.redhat.com Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21cifs: Fix leak when handling lease break for cached root fidPaul Aurich1-21/+52
commit baf57b56d3604880ccb3956ec6c62ea894f5de99 upstream. Handling a lease break for the cached root didn't free the smb2_lease_break_work allocation, resulting in a leak: unreferenced object 0xffff98383a5af480 (size 128): comm "cifsd", pid 684, jiffies 4294936606 (age 534.868s) hex dump (first 32 bytes): c0 ff ff ff 1f 00 00 00 88 f4 5a 3a 38 98 ff ff ..........Z:8... 88 f4 5a 3a 38 98 ff ff 80 88 d6 8a ff ff ff ff ..Z:8........... backtrace: [<0000000068957336>] smb2_is_valid_oplock_break+0x1fa/0x8c0 [<0000000073b70b9e>] cifs_demultiplex_thread+0x73d/0xcc0 [<00000000905fa372>] kthread+0x11c/0x150 [<0000000079378e4e>] ret_from_fork+0x22/0x30 Avoid this leak by only allocating when necessary. Fixes: a93864d93977 ("cifs: add lease tracking to the cached root fid") Signed-off-by: Paul Aurich <paul@darkrain42.org> CC: Stable <stable@vger.kernel.org> # v4.18+ Reviewed-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21btrfs: fix return value mixup in btrfs_get_extentPavel Machek1-1/+1
commit 881a3a11c2b858fe9b69ef79ac5ee9978a266dc9 upstream. btrfs_get_extent() sets variable ret, but out: error path expect error to be in variable err so the error code is lost. Fixes: 6bf9e4bd6a27 ("btrfs: inode: Verify inode mode to avoid NULL pointer dereference") CC: stable@vger.kernel.org # 5.4+ Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Pavel Machek (CIP) <pavel@denx.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21btrfs: make sure SB_I_VERSION doesn't get unset by remountJosef Bacik1-0/+6
commit faa008899a4db21a2df99833cb4ff6fa67009a20 upstream. There's some inconsistency around SB_I_VERSION handling with mount and remount. Since we don't really want it to be off ever just work around this by making sure we don't get the flag cleared on remount. There's a tiny cpu cost of setting the bit, otherwise all changes to i_version also change some of the times (ctime/mtime) so the inode needs to be synced. We wouldn't save anything by disabling it. Reported-by: Eric Sandeen <sandeen@redhat.com> CC: stable@vger.kernel.org # 5.4+ Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> [ add perf impact analysis ] Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21btrfs: fix memory leaks after failure to lookup checksums during inode loggingFilipe Manana1-6/+2
commit 4f26433e9b3eb7a55ed70d8f882ae9cd48ba448b upstream. While logging an inode, at copy_items(), if we fail to lookup the checksums for an extent we release the destination path, free the ins_data array and then return immediately. However a previous iteration of the for loop may have added checksums to the ordered_sums list, in which case we leak the memory used by them. So fix this by making sure we iterate the ordered_sums list and free all its checksums before returning. Fixes: 3650860b90cc2a ("Btrfs: remove almost all of the BUG()'s from tree-log.c") CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21btrfs: inode: fix NULL pointer dereference if inode doesn't need compressionQu Wenruo1-5/+11
commit 1e6e238c3002ea3611465ce5f32777ddd6a40126 upstream. [BUG] There is a bug report of NULL pointer dereference caused in compress_file_extent(): Oops: Kernel access of bad area, sig: 11 [#1] LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries Workqueue: btrfs-delalloc btrfs_delalloc_helper [btrfs] NIP [c008000006dd4d34] compress_file_range.constprop.41+0x75c/0x8a0 [btrfs] LR [c008000006dd4d1c] compress_file_range.constprop.41+0x744/0x8a0 [btrfs] Call Trace: [c000000c69093b00] [c008000006dd4d1c] compress_file_range.constprop.41+0x744/0x8a0 [btrfs] (unreliable) [c000000c69093bd0] [c008000006dd4ebc] async_cow_start+0x44/0xa0 [btrfs] [c000000c69093c10] [c008000006e14824] normal_work_helper+0xdc/0x598 [btrfs] [c000000c69093c80] [c0000000001608c0] process_one_work+0x2c0/0x5b0 [c000000c69093d10] [c000000000160c38] worker_thread+0x88/0x660 [c000000c69093db0] [c00000000016b55c] kthread+0x1ac/0x1c0 [c000000c69093e20] [c00000000000b660] ret_from_kernel_thread+0x5c/0x7c ---[ end trace f16954aa20d822f6 ]--- [CAUSE] For the following execution route of compress_file_range(), it's possible to hit NULL pointer dereference: compress_file_extent() |- pages = NULL; |- start = async_chunk->start = 0; |- end = async_chunk = 4095; |- nr_pages = 1; |- inode_need_compress() == false; <<< Possible, see later explanation | Now, we have nr_pages = 1, pages = NULL |- cont: |- ret = cow_file_range_inline(); |- if (ret <= 0) { |- for (i = 0; i < nr_pages; i++) { |- WARN_ON(pages[i]->mapping); <<< Crash To enter above call execution branch, we need the following race: Thread 1 (chattr) | Thread 2 (writeback) --------------------------+------------------------------ | btrfs_run_delalloc_range | |- inode_need_compress = true | |- cow_file_range_async() btrfs_ioctl_set_flag() | |- binode_flags |= | BTRFS_INODE_NOCOMPRESS | | compress_file_range() | |- inode_need_compress = false | |- nr_page = 1 while pages = NULL | | Then hit the crash [FIX] This patch will fix it by checking @pages before doing accessing it. This patch is only designed as a hot fix and easy to backport. More elegant fix may make btrfs only check inode_need_compress() once to avoid such race, but that would be another story. Reported-by: Luciano Chavez <chavez@us.ibm.com> Fixes: 4d3a800ebb12 ("btrfs: merge nr_pages input and output parameter in compress_pages") CC: stable@vger.kernel.org # 4.14.x: cecc8d9038d16: btrfs: Move free_pages_out label in inline extent handling branch in compress_file_range CC: stable@vger.kernel.org # 4.14+ Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21btrfs: only search for left_info if there is no right_info in ↵Josef Bacik1-2/+2
try_merge_free_space commit bf53d4687b8f3f6b752f091eb85f62369a515dfd upstream. In try_to_merge_free_space we attempt to find entries to the left and right of the entry we are adding to see if they can be merged. We search for an entry past our current info (saved into right_info), and then if right_info exists and it has a rb_prev() we save the rb_prev() into left_info. However there's a slight problem in the case that we have a right_info, but no entry previous to that entry. At that point we will search for an entry just before the info we're attempting to insert. This will simply find right_info again, and assign it to left_info, making them both the same pointer. Now if right_info _can_ be merged with the range we're inserting, we'll add it to the info and free right_info. However further down we'll access left_info, which was right_info, and thus get a use-after-free. Fix this by only searching for the left entry if we don't find a right entry at all. The CVE referenced had a specially crafted file system that could trigger this use-after-free. However with the tree checker improvements we no longer trigger the conditions for the UAF. But the original conditions still apply, hence this fix. Reference: CVE-2019-19448 Fixes: 963030817060 ("Btrfs: use hybrid extents+bitmap rb tree for free space") CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21btrfs: fix messages after changing compression level by remountDavid Sterba1-5/+9
commit 27942c9971cc405c60432eca9395e514a2ae9f5e upstream. Reported by Forza on IRC that remounting with compression options does not reflect the change in level, or at least it does not appear to do so according to the messages: mount -o compress=zstd:1 /dev/sda /mnt mount -o remount,compress=zstd:15 /mnt does not print the change to the level to syslog: [ 41.366060] BTRFS info (device vda): use zstd compression, level 1 [ 41.368254] BTRFS info (device vda): disk space caching is enabled [ 41.390429] BTRFS info (device vda): disk space caching is enabled What really happens is that the message is lost but the level is actualy changed. There's another weird output, if compression is reset to 'no': [ 45.413776] BTRFS info (device vda): use no compression, level 4 To fix that, save the previous compression level and print the message in that case too and use separate message for 'no' compression. CC: stable@vger.kernel.org # 4.19+ Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21btrfs: fix race between page release and a fast fsyncFilipe Manana1-3/+13
commit 3d6448e631591756da36efb3ea6355ff6f383c3a upstream. When releasing an extent map, done through the page release callback, we can race with an ongoing fast fsync and cause the fsync to miss a new extent and not log it. The steps for this to happen are the following: 1) A page is dirtied for some inode I; 2) Writeback for that page is triggered by a path other than fsync, for example by the system due to memory pressure; 3) When the ordered extent for the extent (a single 4K page) finishes, we unpin the corresponding extent map and set its generation to N, the current transaction's generation; 4) The btrfs_releasepage() callback is invoked by the system due to memory pressure for that no longer dirty page of inode I; 5) At the same time, some task calls fsync on inode I, joins transaction N, and at btrfs_log_inode() it sees that the inode does not have the full sync flag set, so we proceed with a fast fsync. But before we get into btrfs_log_changed_extents() and lock the inode's extent map tree: 6) Through btrfs_releasepage() we end up at try_release_extent_mapping() and we remove the extent map for the new 4Kb extent, because it is neither pinned anymore nor locked. By calling remove_extent_mapping(), we remove the extent map from the list of modified extents, since the extent map does not have the logging flag set. We unlock the inode's extent map tree; 7) The task doing the fast fsync now enters btrfs_log_changed_extents(), locks the inode's extent map tree and iterates its list of modified extents, which no longer has the 4Kb extent in it, so it does not log the extent; 8) The fsync finishes; 9) Before transaction N is committed, a power failure happens. After replaying the log, the 4K extent of inode I will be missing, since it was not logged due to the race with try_release_extent_mapping(). So fix this by teaching try_release_extent_mapping() to not remove an extent map if it's still in the list of modified extents. Fixes: ff44c6e36dc9dc ("Btrfs: do not hold the write_lock on the extent tree while logging") CC: stable@vger.kernel.org # 5.4+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21btrfs: don't WARN if we abort a transaction with EROFSJosef Bacik1-1/+1
commit f95ebdbed46a4d8b9fdb7bff109fdbb6fc9a6dc8 upstream. If we got some sort of corruption via a read and call btrfs_handle_fs_error() we'll set BTRFS_FS_STATE_ERROR on the fs and complain. If a subsequent trans handle trips over this it'll get EROFS and then abort. However at that point we're not aborting for the original reason, we're aborting because we've been flipped read only. We do not need to WARN_ON() here. CC: stable@vger.kernel.org # 5.4+ Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21btrfs: sysfs: use NOFS for device creationJosef Bacik1-0/+3
commit a47bd78d0c44621efb98b525d04d60dc4d1a79b0 upstream. Dave hit this splat during testing btrfs/078: ====================================================== WARNING: possible circular locking dependency detected 5.8.0-rc6-default+ #1191 Not tainted ------------------------------------------------------ kswapd0/75 is trying to acquire lock: ffffa040e9d04ff8 (&delayed_node->mutex){+.+.}-{3:3}, at: __btrfs_release_delayed_node.part.0+0x3f/0x310 [btrfs] but task is already holding lock: ffffffff8b0c8040 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x5/0x30 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (fs_reclaim){+.+.}-{0:0}: __lock_acquire+0x56f/0xaa0 lock_acquire+0xa3/0x440 fs_reclaim_acquire.part.0+0x25/0x30 __kmalloc_track_caller+0x49/0x330 kstrdup+0x2e/0x60 __kernfs_new_node.constprop.0+0x44/0x250 kernfs_new_node+0x25/0x50 kernfs_create_link+0x34/0xa0 sysfs_do_create_link_sd+0x5e/0xd0 btrfs_sysfs_add_devices_dir+0x65/0x100 [btrfs] btrfs_init_new_device+0x44c/0x12b0 [btrfs] btrfs_ioctl+0xc3c/0x25c0 [btrfs] ksys_ioctl+0x68/0xa0 __x64_sys_ioctl+0x16/0x20 do_syscall_64+0x50/0xe0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #1 (&fs_info->chunk_mutex){+.+.}-{3:3}: __lock_acquire+0x56f/0xaa0 lock_acquire+0xa3/0x440 __mutex_lock+0xa0/0xaf0 btrfs_chunk_alloc+0x137/0x3e0 [btrfs] find_free_extent+0xb44/0xfb0 [btrfs] btrfs_reserve_extent+0x9b/0x180 [btrfs] btrfs_alloc_tree_block+0xc1/0x350 [btrfs] alloc_tree_block_no_bg_flush+0x4a/0x60 [btrfs] __btrfs_cow_block+0x143/0x7a0 [btrfs] btrfs_cow_block+0x15f/0x310 [btrfs] push_leaf_right+0x150/0x240 [btrfs] split_leaf+0x3cd/0x6d0 [btrfs] btrfs_search_slot+0xd14/0xf70 [btrfs] btrfs_insert_empty_items+0x64/0xc0 [btrfs] __btrfs_commit_inode_delayed_items+0xb2/0x840 [btrfs] btrfs_async_run_delayed_root+0x10e/0x1d0 [btrfs] btrfs_work_helper+0x2f9/0x650 [btrfs] process_one_work+0x22c/0x600 worker_thread+0x50/0x3b0 kthread+0x137/0x150 ret_from_fork+0x1f/0x30 -> #0 (&delayed_node->mutex){+.+.}-{3:3}: check_prev_add+0x98/0xa20 validate_chain+0xa8c/0x2a00 __lock_acquire+0x56f/0xaa0 lock_acquire+0xa3/0x440 __mutex_lock+0xa0/0xaf0 __btrfs_release_delayed_node.part.0+0x3f/0x310 [btrfs] btrfs_evict_inode+0x3bf/0x560 [btrfs] evict+0xd6/0x1c0 dispose_list+0x48/0x70 prune_icache_sb+0x54/0x80 super_cache_scan+0x121/0x1a0 do_shrink_slab+0x175/0x420 shrink_slab+0xb1/0x2e0 shrink_node+0x192/0x600 balance_pgdat+0x31f/0x750 kswapd+0x206/0x510 kthread+0x137/0x150 ret_from_fork+0x1f/0x30 other info that might help us debug this: Chain exists of: &delayed_node->mutex --> &fs_info->chunk_mutex --> fs_reclaim Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(&fs_info->chunk_mutex); lock(fs_reclaim); lock(&delayed_node->mutex); *** DEADLOCK *** 3 locks held by kswapd0/75: #0: ffffffff8b0c8040 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x5/0x30 #1: ffffffff8b0b50b8 (shrinker_rwsem){++++}-{3:3}, at: shrink_slab+0x54/0x2e0 #2: ffffa040e057c0e8 (&type->s_umount_key#26){++++}-{3:3}, at: trylock_super+0x16/0x50 stack backtrace: CPU: 2 PID: 75 Comm: kswapd0 Not tainted 5.8.0-rc6-default+ #1191 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba527-rebuilt.opensuse.org 04/01/2014 Call Trace: dump_stack+0x78/0xa0 check_noncircular+0x16f/0x190 check_prev_add+0x98/0xa20 validate_chain+0xa8c/0x2a00 __lock_acquire+0x56f/0xaa0 lock_acquire+0xa3/0x440 ? __btrfs_release_delayed_node.part.0+0x3f/0x310 [btrfs] __mutex_lock+0xa0/0xaf0 ? __btrfs_release_delayed_node.part.0+0x3f/0x310 [btrfs] ? __lock_acquire+0x56f/0xaa0 ? __btrfs_release_delayed_node.part.0+0x3f/0x310 [btrfs] ? lock_acquire+0xa3/0x440 ? btrfs_evict_inode+0x138/0x560 [btrfs] ? btrfs_evict_inode+0x2fe/0x560 [btrfs] ? __btrfs_release_delayed_node.part.0+0x3f/0x310 [btrfs] __btrfs_release_delayed_node.part.0+0x3f/0x310 [btrfs] btrfs_evict_inode+0x3bf/0x560 [btrfs] evict+0xd6/0x1c0 dispose_list+0x48/0x70 prune_icache_sb+0x54/0x80 super_cache_scan+0x121/0x1a0 do_shrink_slab+0x175/0x420 shrink_slab+0xb1/0x2e0 shrink_node+0x192/0x600 balance_pgdat+0x31f/0x750 kswapd+0x206/0x510 ? _raw_spin_unlock_irqrestore+0x3e/0x50 ? finish_wait+0x90/0x90 ? balance_pgdat+0x750/0x750 kthread+0x137/0x150 ? kthread_stop+0x2a0/0x2a0 ret_from_fork+0x1f/0x30 This is because we're holding the chunk_mutex while adding this device and adding its sysfs entries. We actually hold different locks in different places when calling this function, the dev_replace semaphore for instance in dev replace, so instead of moving this call around simply wrap it's operations in NOFS. CC: stable@vger.kernel.org # 4.14+ Reported-by: David Sterba <dsterba@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21btrfs: avoid possible signal interruption of btrfs_drop_snapshot() on ↵Qu Wenruo1-1/+8
relocation tree commit f3e3d9cc35252a70a2fd698762c9687718268ec6 upstream. [BUG] There is a bug report about bad signal timing could lead to read-only fs during balance: BTRFS info (device xvdb): balance: start -d -m -s BTRFS info (device xvdb): relocating block group 73001861120 flags metadata BTRFS info (device xvdb): found 12236 extents, stage: move data extents BTRFS info (device xvdb): relocating block group 71928119296 flags data BTRFS info (device xvdb): found 3 extents, stage: move data extents BTRFS info (device xvdb): found 3 extents, stage: update data pointers BTRFS info (device xvdb): relocating block group 60922265600 flags metadata BTRFS: error (device xvdb) in btrfs_drop_snapshot:5505: errno=-4 unknown BTRFS info (device xvdb): forced readonly BTRFS info (device xvdb): balance: ended with status: -4 [CAUSE] The direct cause is the -EINTR from the following call chain when a fatal signal is pending: relocate_block_group() |- clean_dirty_subvols() |- btrfs_drop_snapshot() |- btrfs_start_transaction() |- btrfs_delayed_refs_rsv_refill() |- btrfs_reserve_metadata_bytes() |- __reserve_metadata_bytes() |- wait_reserve_ticket() |- prepare_to_wait_event(); |- ticket->error = -EINTR; Normally this behavior is fine for most btrfs_start_transaction() callers, as they need to catch any other error, same for the signal, and exit ASAP. However for balance, especially for the clean_dirty_subvols() case, we're already doing cleanup works, getting -EINTR from btrfs_drop_snapshot() could cause a lot of unexpected problems. From the mentioned forced read-only report, to later balance error due to half dropped reloc trees. [FIX] Fix this problem by using btrfs_join_transaction() if btrfs_drop_snapshot() is called from relocation context. Since btrfs_join_transaction() won't get interrupted by signal, we can continue the cleanup. CC: stable@vger.kernel.org # 5.4+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com>3 Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21btrfs: add missing check for nocow and compression inode flagsDavid Sterba1-8/+22
commit f37c563bab4297024c300b05c8f48430e323809d upstream. User Forza reported on IRC that some invalid combinations of file attributes are accepted by chattr. The NODATACOW and compression file flags/attributes are mutually exclusive, but they could be set by 'chattr +c +C' on an empty file. The nodatacow will be in effect because it's checked first in btrfs_run_delalloc_range. Extend the flag validation to catch the following cases: - input flags are conflicting - old and new flags are conflicting - initialize the local variable with inode flags after inode ls locked Inode attributes take precedence over mount options and are an independent setting. Nocompress would be a no-op with nodatacow, but we don't want to mix any compression-related options with nodatacow. CC: stable@vger.kernel.org # 4.4+ Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21btrfs: relocation: review the call sites which can be interrupted by signalQu Wenruo2-3/+26
commit 44d354abf33e92a5e73b965c84caf5a5d5e58a0b upstream. Since most metadata reservation calls can return -EINTR when get interrupted by fatal signal, we need to review the all the metadata reservation call sites. In relocation code, the metadata reservation happens in the following sites: - btrfs_block_rsv_refill() in merge_reloc_root() merge_reloc_root() is a pretty critical section, we don't want to be interrupted by signal, so change the flush status to BTRFS_RESERVE_FLUSH_LIMIT, so it won't get interrupted by signal. Since such change can be ENPSPC-prone, also shrink the amount of metadata to reserve least amount avoid deadly ENOSPC there. - btrfs_block_rsv_refill() in reserve_metadata_space() It calls with BTRFS_RESERVE_FLUSH_LIMIT, which won't get interrupted by signal. - btrfs_block_rsv_refill() in prepare_to_relocate() - btrfs_block_rsv_add() in prepare_to_relocate() - btrfs_block_rsv_refill() in relocate_block_group() - btrfs_delalloc_reserve_metadata() in relocate_file_extent_cluster() - btrfs_start_transaction() in relocate_block_group() - btrfs_start_transaction() in create_reloc_inode() Can be interrupted by fatal signal and we can handle it easily. For these call sites, just catch the -EINTR value in btrfs_balance() and count them as canceled. CC: stable@vger.kernel.org # 5.4+ Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21btrfs: move the chunk_mutex in btrfs_read_chunk_treeJosef Bacik1-2/+2
commit 01d01caf19ff7c537527d352d169c4368375c0a1 upstream. We are currently getting this lockdep splat in btrfs/161: ====================================================== WARNING: possible circular locking dependency detected 5.8.0-rc5+ #20 Tainted: G E ------------------------------------------------------ mount/678048 is trying to acquire lock: ffff9b769f15b6e0 (&fs_devs->device_list_mutex){+.+.}-{3:3}, at: clone_fs_devices+0x4d/0x170 [btrfs] but task is already holding lock: ffff9b76abdb08d0 (&fs_info->chunk_mutex){+.+.}-{3:3}, at: btrfs_read_chunk_tree+0x6a/0x800 [btrfs] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&fs_info->chunk_mutex){+.+.}-{3:3}: __mutex_lock+0x8b/0x8f0 btrfs_init_new_device+0x2d2/0x1240 [btrfs] btrfs_ioctl+0x1de/0x2d20 [btrfs] ksys_ioctl+0x87/0xc0 __x64_sys_ioctl+0x16/0x20 do_syscall_64+0x52/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #0 (&fs_devs->device_list_mutex){+.+.}-{3:3}: __lock_acquire+0x1240/0x2460 lock_acquire+0xab/0x360 __mutex_lock+0x8b/0x8f0 clone_fs_devices+0x4d/0x170 [btrfs] btrfs_read_chunk_tree+0x330/0x800 [btrfs] open_ctree+0xb7c/0x18ce [btrfs] btrfs_mount_root.cold+0x13/0xfa [btrfs] legacy_get_tree+0x30/0x50 vfs_get_tree+0x28/0xc0 fc_mount+0xe/0x40 vfs_kern_mount.part.0+0x71/0x90 btrfs_mount+0x13b/0x3e0 [btrfs] legacy_get_tree+0x30/0x50 vfs_get_tree+0x28/0xc0 do_mount+0x7de/0xb30 __x64_sys_mount+0x8e/0xd0 do_syscall_64+0x52/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&fs_info->chunk_mutex); lock(&fs_devs->device_list_mutex); lock(&fs_info->chunk_mutex); lock(&fs_devs->device_list_mutex); *** DEADLOCK *** 3 locks held by mount/678048: #0: ffff9b75ff5fb0e0 (&type->s_umount_key#63/1){+.+.}-{3:3}, at: alloc_super+0xb5/0x380 #1: ffffffffc0c2fbc8 (uuid_mutex){+.+.}-{3:3}, at: btrfs_read_chunk_tree+0x54/0x800 [btrfs] #2: ffff9b76abdb08d0 (&fs_info->chunk_mutex){+.+.}-{3:3}, at: btrfs_read_chunk_tree+0x6a/0x800 [btrfs] stack backtrace: CPU: 2 PID: 678048 Comm: mount Tainted: G E 5.8.0-rc5+ #20 Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./890FX Deluxe5, BIOS P1.40 05/03/2011 Call Trace: dump_stack+0x96/0xd0 check_noncircular+0x162/0x180 __lock_acquire+0x1240/0x2460 ? asm_sysvec_apic_timer_interrupt+0x12/0x20 lock_acquire+0xab/0x360 ? clone_fs_devices+0x4d/0x170 [btrfs] __mutex_lock+0x8b/0x8f0 ? clone_fs_devices+0x4d/0x170 [btrfs] ? rcu_read_lock_sched_held+0x52/0x60 ? cpumask_next+0x16/0x20 ? module_assert_mutex_or_preempt+0x14/0x40 ? __module_address+0x28/0xf0 ? clone_fs_devices+0x4d/0x170 [btrfs] ? static_obj+0x4f/0x60 ? lockdep_init_map_waits+0x43/0x200 ? clone_fs_devices+0x4d/0x170 [btrfs] clone_fs_devices+0x4d/0x170 [btrfs] btrfs_read_chunk_tree+0x330/0x800 [btrfs] open_ctree+0xb7c/0x18ce [btrfs] ? super_setup_bdi_name+0x79/0xd0 btrfs_mount_root.cold+0x13/0xfa [btrfs] ? vfs_parse_fs_string+0x84/0xb0 ? rcu_read_lock_sched_held+0x52/0x60 ? kfree+0x2b5/0x310 legacy_get_tree+0x30/0x50 vfs_get_tree+0x28/0xc0 fc_mount+0xe/0x40 vfs_kern_mount.part.0+0x71/0x90 btrfs_mount+0x13b/0x3e0 [btrfs] ? cred_has_capability+0x7c/0x120 ? rcu_read_lock_sched_held+0x52/0x60 ? legacy_get_tree+0x30/0x50 legacy_get_tree+0x30/0x50 vfs_get_tree+0x28/0xc0 do_mount+0x7de/0xb30 ? memdup_user+0x4e/0x90 __x64_sys_mount+0x8e/0xd0 do_syscall_64+0x52/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 This is because btrfs_read_chunk_tree() can come upon DEV_EXTENT's and then read the device, which takes the device_list_mutex. The device_list_mutex needs to be taken before the chunk_mutex, so this is a problem. We only really need the chunk mutex around adding the chunk, so move the mutex around read_one_chunk. An argument could be made that we don't even need the chunk_mutex here as it's during mount, and we are protected by various other locks. However we already have special rules for ->device_list_mutex, and I'd rather not have another special case for ->chunk_mutex. CC: stable@vger.kernel.org # 4.19+ Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21btrfs: open device without device_list_mutexJosef Bacik1-3/+18
commit 18c850fdc5a801bad4977b0f1723761d42267e45 upstream. There's long existed a lockdep splat because we open our bdev's under the ->device_list_mutex at mount time, which acquires the bd_mutex. Usually this goes unnoticed, but if you do loopback devices at all suddenly the bd_mutex comes with a whole host of other dependencies, which results in the splat when you mount a btrfs file system. ====================================================== WARNING: possible circular locking dependency detected 5.8.0-0.rc3.1.fc33.x86_64+debug #1 Not tainted ------------------------------------------------------ systemd-journal/509 is trying to acquire lock: ffff970831f84db0 (&fs_info->reloc_mutex){+.+.}-{3:3}, at: btrfs_record_root_in_trans+0x44/0x70 [btrfs] but task is already holding lock: ffff97083144d598 (sb_pagefaults){.+.+}-{0:0}, at: btrfs_page_mkwrite+0x59/0x560 [btrfs] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #6 (sb_pagefaults){.+.+}-{0:0}: __sb_start_write+0x13e/0x220 btrfs_page_mkwrite+0x59/0x560 [btrfs] do_page_mkwrite+0x4f/0x130 do_wp_page+0x3b0/0x4f0 handle_mm_fault+0xf47/0x1850 do_user_addr_fault+0x1fc/0x4b0 exc_page_fault+0x88/0x300 asm_exc_page_fault+0x1e/0x30 -> #5 (&mm->mmap_lock#2){++++}-{3:3}: __might_fault+0x60/0x80 _copy_from_user+0x20/0xb0 get_sg_io_hdr+0x9a/0xb0 scsi_cmd_ioctl+0x1ea/0x2f0 cdrom_ioctl+0x3c/0x12b4 sr_block_ioctl+0xa4/0xd0 block_ioctl+0x3f/0x50 ksys_ioctl+0x82/0xc0 __x64_sys_ioctl+0x16/0x20 do_syscall_64+0x52/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #4 (&cd->lock){+.+.}-{3:3}: __mutex_lock+0x7b/0x820 sr_block_open+0xa2/0x180 __blkdev_get+0xdd/0x550 blkdev_get+0x38/0x150 do_dentry_open+0x16b/0x3e0 path_openat+0x3c9/0xa00 do_filp_open+0x75/0x100 do_sys_openat2+0x8a/0x140 __x64_sys_openat+0x46/0x70 do_syscall_64+0x52/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #3 (&bdev->bd_mutex){+.+.}-{3:3}: __mutex_lock+0x7b/0x820 __blkdev_get+0x6a/0x550 blkdev_get+0x85/0x150 blkdev_get_by_path+0x2c/0x70 btrfs_get_bdev_and_sb+0x1b/0xb0 [btrfs] open_fs_devices+0x88/0x240 [btrfs] btrfs_open_devices+0x92/0xa0 [btrfs] btrfs_mount_root+0x250/0x490 [btrfs] legacy_get_tree+0x30/0x50 vfs_get_tree+0x28/0xc0 vfs_kern_mount.part.0+0x71/0xb0 btrfs_mount+0x119/0x380 [btrfs] legacy_get_tree+0x30/0x50 vfs_get_tree+0x28/0xc0 do_mount+0x8c6/0xca0 __x64_sys_mount+0x8e/0xd0 do_syscall_64+0x52/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #2 (&fs_devs->device_list_mutex){+.+.}-{3:3}: __mutex_lock+0x7b/0x820 btrfs_run_dev_stats+0x36/0x420 [btrfs] commit_cowonly_roots+0x91/0x2d0 [btrfs] btrfs_commit_transaction+0x4e6/0x9f0 [btrfs] btrfs_sync_file+0x38a/0x480 [btrfs] __x64_sys_fdatasync+0x47/0x80 do_syscall_64+0x52/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #1 (&fs_info->tree_log_mutex){+.+.}-{3:3}: __mutex_lock+0x7b/0x820 btrfs_commit_transaction+0x48e/0x9f0 [btrfs] btrfs_sync_file+0x38a/0x480 [btrfs] __x64_sys_fdatasync+0x47/0x80 do_syscall_64+0x52/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #0 (&fs_info->reloc_mutex){+.+.}-{3:3}: __lock_acquire+0x1241/0x20c0 lock_acquire+0xb0/0x400 __mutex_lock+0x7b/0x820 btrfs_record_root_in_trans+0x44/0x70 [btrfs] start_transaction+0xd2/0x500 [btrfs] btrfs_dirty_inode+0x44/0xd0 [btrfs] file_update_time+0xc6/0x120 btrfs_page_mkwrite+0xda/0x560 [btrfs] do_page_mkwrite+0x4f/0x130 do_wp_page+0x3b0/0x4f0 handle_mm_fault+0xf47/0x1850 do_user_addr_fault+0x1fc/0x4b0 exc_page_fault+0x88/0x300 asm_exc_page_fault+0x1e/0x30 other info that might help us debug this: Chain exists of: &fs_info->reloc_mutex --> &mm->mmap_lock#2 --> sb_pagefaults Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(sb_pagefaults); lock(&mm->mmap_lock#2); lock(sb_pagefaults); lock(&fs_info->reloc_mutex); *** DEADLOCK *** 3 locks held by systemd-journal/509: #0: ffff97083bdec8b8 (&mm->mmap_lock#2){++++}-{3:3}, at: do_user_addr_fault+0x12e/0x4b0 #1: ffff97083144d598 (sb_pagefaults){.+.+}-{0:0}, at: btrfs_page_mkwrite+0x59/0x560 [btrfs] #2: ffff97083144d6a8 (sb_internal){.+.+}-{0:0}, at: start_transaction+0x3f8/0x500 [btrfs] stack backtrace: CPU: 0 PID: 509 Comm: systemd-journal Not tainted 5.8.0-0.rc3.1.fc33.x86_64+debug #1 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 Call Trace: dump_stack+0x92/0xc8 check_noncircular+0x134/0x150 __lock_acquire+0x1241/0x20c0 lock_acquire+0xb0/0x400 ? btrfs_record_root_in_trans+0x44/0x70 [btrfs] ? lock_acquire+0xb0/0x400 ? btrfs_record_root_in_trans+0x44/0x70 [btrfs] __mutex_lock+0x7b/0x820 ? btrfs_record_root_in_trans+0x44/0x70 [btrfs] ? kvm_sched_clock_read+0x14/0x30 ? sched_clock+0x5/0x10 ? sched_clock_cpu+0xc/0xb0 btrfs_record_root_in_trans+0x44/0x70 [btrfs] start_transaction+0xd2/0x500 [btrfs] btrfs_dirty_inode+0x44/0xd0 [btrfs] file_update_time+0xc6/0x120 btrfs_page_mkwrite+0xda/0x560 [btrfs] ? sched_clock+0x5/0x10 do_page_mkwrite+0x4f/0x130 do_wp_page+0x3b0/0x4f0 handle_mm_fault+0xf47/0x1850 do_user_addr_fault+0x1fc/0x4b0 exc_page_fault+0x88/0x300 ? asm_exc_page_fault+0x8/0x30 asm_exc_page_fault+0x1e/0x30 RIP: 0033:0x7fa3972fdbfe Code: Bad RIP value. Fix this by not holding the ->device_list_mutex at this point. The device_list_mutex exists to protect us from modifying the device list while the file system is running. However it can also be modified by doing a scan on a device. But this action is specifically protected by the uuid_mutex, which we are holding here. We cannot race with opening at this point because we have the ->s_mount lock held during the mount. Not having the ->device_list_mutex here is perfectly safe as we're not going to change the devices at this point. CC: stable@vger.kernel.org # 4.19+ Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> [ add some comments ] Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21btrfs: don't traverse into the seed devices in show_devnameAnand Jain1-14/+7
commit 4faf55b03823e96c44dc4e364520000ed3b12fdb upstream. ->show_devname currently shows the lowest devid in the list. As the seed devices have the lowest devid in the sprouted filesystem, the userland tool such as findmnt end up seeing seed device instead of the device from the read-writable sprouted filesystem. As shown below. mount /dev/sda /btrfs mount: /btrfs: WARNING: device write-protected, mounted read-only. findmnt --output SOURCE,TARGET,UUID /btrfs SOURCE TARGET UUID /dev/sda /btrfs 899f7027-3e46-4626-93e7-7d4c9ad19111 btrfs dev add -f /dev/sdb /btrfs umount /btrfs mount /dev/sdb /btrfs findmnt --output SOURCE,TARGET,UUID /btrfs SOURCE TARGET UUID /dev/sda /btrfs 899f7027-3e46-4626-93e7-7d4c9ad19111 All sprouts from a single seed will show the same seed device and the same fsid. That's confusing. This is causing problems in our prototype as there isn't any reference to the sprout file-system(s) which is being used for actual read and write. This was added in the patch which implemented the show_devname in btrfs commit 9c5085c14798 ("Btrfs: implement ->show_devname"). I tried to look for any particular reason that we need to show the seed device, there isn't any. So instead, do not traverse through the seed devices, just show the lowest devid in the sprouted fsid. After the patch: mount /dev/sda /btrfs mount: /btrfs: WARNING: device write-protected, mounted read-only. findmnt --output SOURCE,TARGET,UUID /btrfs SOURCE TARGET UUID /dev/sda /btrfs 899f7027-3e46-4626-93e7-7d4c9ad19111 btrfs dev add -f /dev/sdb /btrfs mount -o rw,remount /dev/sdb /btrfs findmnt --output SOURCE,TARGET,UUID /btrfs SOURCE TARGET UUID /dev/sdb /btrfs 595ca0e6-b82e-46b5-b9e2-c72a6928be48 mount /dev/sda /btrfs1 mount: /btrfs1: WARNING: device write-protected, mounted read-only. btrfs dev add -f /dev/sdc /btrfs1 findmnt --output SOURCE,TARGET,UUID /btrfs1 SOURCE TARGET UUID /dev/sdc /btrfs1 ca1dbb7a-8446-4f95-853c-a20f3f82bdbb cat /proc/self/mounts | grep btrfs /dev/sdb /btrfs btrfs rw,relatime,noacl,space_cache,subvolid=5,subvol=/ 0 0 /dev/sdc /btrfs1 btrfs ro,relatime,noacl,space_cache,subvolid=5,subvol=/ 0 0 Reported-by: Martin K. Petersen <martin.petersen@oracle.com> CC: stable@vger.kernel.org # 4.19+ Tested-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21btrfs: remove no longer needed use of log_writers for the log root treeFilipe Manana2-13/+1
commit a93e01682e283f6de09d6ce8f805dc52a2e942fb upstream. When syncing the log, we used to update the log root tree without holding neither the log_mutex of the subvolume root nor the log_mutex of log root tree. We used to have two critical sections delimited by the log_mutex of the log root tree, so in the first one we incremented the log_writers of the log root tree and on the second one we decremented it and waited for the log_writers counter to go down to zero. This was because the update of the log root tree happened between the two critical sections. The use of two critical sections allowed a little bit more of parallelism and required the use of the log_writers counter, necessary to make sure we didn't miss any log root tree update when we have multiple tasks trying to sync the log in parallel. However after commit 06989c799f0481 ("Btrfs: fix race updating log root item during fsync") the log root tree update was moved into a critical section delimited by the subvolume's log_mutex. Later another commit moved the log tree update from that critical section into the second critical section delimited by the log_mutex of the log root tree. Both commits addressed different bugs. The end result is that the first critical section delimited by the log_mutex of the log root tree became pointless, since there's nothing done between it and the second critical section, we just have an unlock of the log_mutex followed by a lock operation. This means we can merge both critical sections, as the first one does almost nothing now, and we can stop using the log_writers counter of the log root tree, which was incremented in the first critical section and decremented in the second criticial section, used to make sure no one in the second critical section started writeback of the log root tree before some other task updated it. So just remove the mutex_unlock() followed by mutex_lock() of the log root tree, as well as the use of the log_writers counter for the log root tree. This patch is part of a series that has the following patches: 1/4 btrfs: only commit the delayed inode when doing a full fsync 2/4 btrfs: only commit delayed items at fsync if we are logging a directory 3/4 btrfs: stop incremening log_batch for the log root tree when syncing log 4/4 btrfs: remove no longer needed use of log_writers for the log root tree After the entire patchset applied I saw about 12% decrease on max latency reported by dbench. The test was done on a qemu vm, with 8 cores, 16Gb of ram, using kvm and using a raw NVMe device directly (no intermediary fs on the host). The test was invoked like the following: mkfs.btrfs -f /dev/sdk mount -o ssd -o nospace_cache /dev/sdk /mnt/sdk dbench -D /mnt/sdk -t 300 8 umount /mnt/dsk CC: stable@vger.kernel.org # 5.4+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21btrfs: stop incremening log_batch for the log root tree when syncing logFilipe Manana2-1/+1
commit 28a9579561bcb9082715e720eac93012e708ab94 upstream. We are incrementing the log_batch atomic counter of the root log tree but we never use that counter, it's used only for the log trees of subvolume roots. We started doing it when we moved the log_batch and log_write counters from the global, per fs, btrfs_fs_info structure, into the btrfs_root structure in commit 7237f1833601dc ("Btrfs: fix tree logs parallel sync"). So just stop doing it for the log root tree and add a comment over the field declaration so inform it's used only for log trees of subvolume roots. This patch is part of a series that has the following patches: 1/4 btrfs: only commit the delayed inode when doing a full fsync 2/4 btrfs: only commit delayed items at fsync if we are logging a directory 3/4 btrfs: stop incremening log_batch for the log root tree when syncing log 4/4 btrfs: remove no longer needed use of log_writers for the log root tree After the entire patchset applied I saw about 12% decrease on max latency reported by dbench. The test was done on a qemu vm, with 8 cores, 16Gb of ram, using kvm and using a raw NVMe device directly (no intermediary fs on the host). The test was invoked like the following: mkfs.btrfs -f /dev/sdk mount -o ssd -o nospace_cache /dev/sdk /mnt/sdk dbench -D /mnt/sdk -t 300 8 umount /mnt/dsk CC: stable@vger.kernel.org # 5.4+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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