BMC/Intel-BMC/linux.git/fs/xfs, branch dev-5.8

xfs: Fix UBSAN null-ptr-deref in xfs_sysfs_init

2020-08-26T09:49:07+00:00

[ 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 Reviewed-by: Darrick J. Wong [darrick: minor whitespace edits] Signed-off-by: Darrick J. Wong Signed-off-by: Sasha Levin

xfs: fix inode quota reservation checks

2020-08-26T09:49:05+00:00

[ 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 Reviewed-by: Allison Collins Reviewed-by: Chandan Babu R Reviewed-by: Christoph Hellwig Signed-off-by: Sasha Levin

xfs: clear XFS_DQ_FREEING if we can't lock the dquot buffer to flush

2020-08-19T06:26:47+00:00

[ Upstream commit c97738a960a86081a147e7d436138e6481757445 ] In commit 8d3d7e2b35ea, we changed xfs_qm_dqpurge to bail out if we can't lock the dquot buf to flush the dquot. This prevents the AIL from blocking on the dquot, but it also forgets to clear the FREEING flag on its way out. A subsequent purge attempt will see the FREEING flag is set and bail out, which leads to dqpurge_all failing to purge all the dquots. (copy-pasting from Dave Chinner's identical patch) This was found by inspection after having xfs/305 hang 1 in ~50 iterations in a quotaoff operation: [ 8872.301115] xfs_quota D13888 92262 91813 0x00004002 [ 8872.302538] Call Trace: [ 8872.303193] __schedule+0x2d2/0x780 [ 8872.304108] ? do_raw_spin_unlock+0x57/0xd0 [ 8872.305198] schedule+0x6e/0xe0 [ 8872.306021] schedule_timeout+0x14d/0x300 [ 8872.307060] ? __next_timer_interrupt+0xe0/0xe0 [ 8872.308231] ? xfs_qm_dqusage_adjust+0x200/0x200 [ 8872.309422] schedule_timeout_uninterruptible+0x2a/0x30 [ 8872.310759] xfs_qm_dquot_walk.isra.0+0x15a/0x1b0 [ 8872.311971] xfs_qm_dqpurge_all+0x7f/0x90 [ 8872.313022] xfs_qm_scall_quotaoff+0x18d/0x2b0 [ 8872.314163] xfs_quota_disable+0x3a/0x60 [ 8872.315179] kernel_quotactl+0x7e2/0x8d0 [ 8872.316196] ? __do_sys_newstat+0x51/0x80 [ 8872.317238] __x64_sys_quotactl+0x1e/0x30 [ 8872.318266] do_syscall_64+0x46/0x90 [ 8872.319193] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 8872.320490] RIP: 0033:0x7f46b5490f2a [ 8872.321414] Code: Bad RIP value. Returning -EAGAIN from xfs_qm_dqpurge() without clearing the XFS_DQ_FREEING flag means the xfs_qm_dqpurge_all() code can never free the dquot, and we loop forever waiting for the XFS_DQ_FREEING flag to go away on the dquot that leaked it via -EAGAIN. Fixes: 8d3d7e2b35ea ("xfs: trylock underlying buffer on dquot flush") Signed-off-by: Darrick J. Wong Reviewed-by: Allison Collins Reviewed-by: Chandan Babu R Reviewed-by: Christoph Hellwig Reviewed-by: Brian Foster Signed-off-by: Dave Chinner Reviewed-by: Dave Chinner Signed-off-by: Sasha Levin

xfs: fix inode allocation block res calculation precedence

2020-08-19T06:26:47+00:00

[ Upstream commit b2a8864728683443f34a9fd33a2b78b860934cc1 ] The block reservation calculation for inode allocation is supposed to consist of the blocks required for the inode chunk plus (maxlevels-1) of the inode btree multiplied by the number of inode btrees in the fs (2 when finobt is enabled, 1 otherwise). Instead, the macro returns (ialloc_blocks + 2) due to a precedence error in the calculation logic. This leads to block reservation overruns via generic/531 on small block filesystems with finobt enabled. Add braces to fix the calculation and reserve the appropriate number of blocks. Fixes: 9d43b180af67 ("xfs: update inode allocation/free transaction reservations for finobt") Signed-off-by: Brian Foster Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong Reviewed-by: Christoph Hellwig Signed-off-by: Sasha Levin

xfs: fix reflink quota reservation accounting error

2020-08-19T06:26:32+00:00

[ Upstream commit 83895227aba1ade33e81f586aa7b6b1e143096a5 ] Quota reservations are supposed to account for the blocks that might be allocated due to a bmap btree split. Reflink doesn't do this, so fix this to make the quota accounting more accurate before we start rearranging things. Fixes: 862bb360ef56 ("xfs: reflink extents from one file to another") Signed-off-by: Darrick J. Wong Reviewed-by: Brian Foster Signed-off-by: Sasha Levin

xfs: don't eat an EIO/ENOSPC writeback error when scrubbing data fork

2020-08-19T06:26:32+00:00

[ Upstream commit eb0efe5063bb10bcb653e4f8e92a74719c03a347 ] The data fork scrubber calls filemap_write_and_wait to flush dirty pages and delalloc reservations out to disk prior to checking the data fork's extent mappings. Unfortunately, this means that scrub can consume the EIO/ENOSPC errors that would otherwise have stayed around in the address space until (we hope) the writer application calls fsync to persist data and collect errors. The end result is that programs that wrote to a file might never see the error code and proceed as if nothing were wrong. xfs_scrub is not in a position to notify file writers about the writeback failure, and it's only here to check metadata, not file contents. Therefore, if writeback fails, we should stuff the error code back into the address space so that an fsync by the writer application can pick that up. Fixes: 99d9d8d05da2 ("xfs: scrub inode block mappings") Signed-off-by: Darrick J. Wong Reviewed-by: Brian Foster Reviewed-by: Dave Chinner Signed-off-by: Sasha Levin

xfs: preserve rmapbt swapext block reservation from freed blocks

2020-08-19T06:26:32+00:00

[ Upstream commit f74681ba2006434be195402e0b15fc5763cddd7e ] The rmapbt extent swap algorithm remaps individual extents between the source inode and the target to trigger reverse mapping metadata updates. If either inode straddles a format or other bmap allocation boundary, the individual unmap and map cycles can trigger repeated bmap block allocations and frees as the extent count bounces back and forth across the boundary. While net block usage is bound across the swap operation, this behavior can prematurely exhaust the transaction block reservation because it continuously drains as the transaction rolls. Each allocation accounts against the reservation and each free returns to global free space on transaction roll. The previous workaround to this problem attempted to detect this boundary condition and provide surplus block reservation to acommodate it. This is insufficient because more remaps can occur than implied by the extent counts; if start offset boundaries are not aligned between the two inodes, for example. To address this problem more generically and dynamically, add a transaction accounting mode that returns freed blocks to the transaction reservation instead of the superblock counters on transaction roll and use it when the rmapbt based algorithm is active. This allows the chain of remap transactions to preserve the block reservation based own its own frees and prevent premature exhaustion regardless of the remap pattern. Note that this is only safe for superblocks with lazy sb accounting, but the latter is required for v5 supers and the rmap feature depends on v5. Fixes: b3fed434822d0 ("xfs: account format bouncing into rmapbt swapext tx reservation") Root-caused-by: Darrick J. Wong Signed-off-by: Brian Foster Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong Signed-off-by: Sasha Levin

xfs: fix use-after-free on CIL context on shutdown

2020-06-23T02:22:57+00:00

xlog_wait() on the CIL context can reference a freed context if the waiter doesn't get scheduled before the CIL context is freed. This can happen when a task is on the hard throttle and the CIL push aborts due to a shutdown. This was detected by generic/019: thread 1 thread 2 __xfs_trans_commit xfs_log_commit_cil xlog_wait schedule xlog_cil_push_work wake_up_all xlog_cil_committed kmem_free remove_wait_queue spin_lock_irqsave --> UAF Fix it by moving the wait queue to the CIL rather than keeping it in in the CIL context that gets freed on push completion. Because the wait queue is now independent of the CIL context and we might have multiple contexts in flight at once, only wake the waiters on the push throttle when the context we are pushing is over the hard throttle size threshold. Fixes: 0e7ab7efe7745 ("xfs: Throttle commits on delayed background CIL push") Reported-by: Yu Kuai Signed-off-by: Dave Chinner Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong Reviewed-by: Christoph Hellwig

Merge tag 'xfs-5.8-merge-9' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

2020-06-13T19:40:24+00:00

Pull xfs fix from Darrick Wong: "We've settled down into the bugfix phase; this one fixes a resource leak on an error bailout path" * tag 'xfs-5.8-merge-9' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: xfs: Add the missed xfs_perag_put() for xfs_ifree_cluster()

Merge tag 'vfs-5.8-merge-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

2020-06-11T17:48:12+00:00

Pull DAX updates part three from Darrick Wong: "Now that the xfs changes have landed, this third piece changes the FS_XFLAG_DAX ioctl code in xfs to request that the inode be reloaded after the last program closes the file, if doing so would make a S_DAX change happen. The goal here is to make dax access mode switching quicker when possible. Summary: - Teach XFS to ask the VFS to drop an inode if the administrator changes the FS_XFLAG_DAX inode flag such that the S_DAX state would change. This can result in files changing access modes without requiring an unmount cycle" * tag 'vfs-5.8-merge-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: fs/xfs: Update xfs_ioctl_setattr_dax_invalidate() fs/xfs: Combine xfs_diflags_to_linux() and xfs_diflags_to_iflags() fs/xfs: Create function xfs_inode_should_enable_dax() fs/xfs: Make DAX mount option a tri-state fs/xfs: Change XFS_MOUNT_DAX to XFS_MOUNT_DAX_ALWAYS fs/xfs: Remove unnecessary initialization of i_rwsem