user/sven/linux.git/fs, branch v4.14.23

btrfs: Fix possible off-by-one in btrfs_search_path_in_tree

2018-02-25T10:08:00Z

[ Upstream commit c8bcbfbd239ed60a6562964b58034ac8a25f4c31 ] The name char array passed to btrfs_search_path_in_tree is of size BTRFS_INO_LOOKUP_PATH_MAX (4080). So the actual accessible char indexes are in the range of [0, 4079]. Currently the code uses the define but this represents an off-by-one. Implications: Size of btrfs_ioctl_ino_lookup_args is 4096, so the new byte will be written to extra space, not some padding that could be provided by the allocator. btrfs-progs store the arguments on stack, but kernel does own copy of the ioctl buffer and the off-by-one overwrite does not affect userspace, but the ending 0 might be lost. Kernel ioctl buffer is allocated dynamically so we're overwriting somebody else's memory, and the ioctl is privileged if args.objectid is not 256. Which is in most cases, but resolving a subvolume stored in another directory will trigger that path. Before this patch the buffer was one byte larger, but then the -1 was not added. Fixes: ac8e9819d71f907 ("Btrfs: add search and inode lookup ioctls") Signed-off-by: Nikolay Borisov Reviewed-by: David Sterba [ added implications ] Signed-off-by: David Sterba Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

Btrfs: disable FUA if mounted with nobarrier

2018-02-25T10:08:00Z

[ Upstream commit 1b9e619c5bc8235cfba3dc4ced2fb0e3554a05d4 ] I was seeing disk flushes still happening when I mounted a Btrfs filesystem with nobarrier for testing. This is because we use FUA to write out the first super block, and on devices without FUA support, the block layer translates FUA to a flush. Even on devices supporting true FUA, using FUA when we asked for no barriers is surprising. Fixes: 387125fc722a8ed ("Btrfs: fix barrier flushes") Signed-off-by: Omar Sandoval Reviewed-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

btrfs: Fix quota reservation leak on preallocated files

2018-02-25T10:08:00Z

[ Upstream commit b430b7751286b3acff2d324553c8cec4f1e87764 ] Commit c6887cd11149 ("Btrfs: don't do nocow check unless we have to") changed the behavior of __btrfs_buffered_write() so that it first tries to get a data space reservation, and then skips the relatively expensive nocow check if the reservation succeeded. If we have quotas enabled, the data space reservation also includes a quota reservation. But in the rewrite case, the space has already been accounted for in qgroups. So btrfs_check_data_free_space() increases the quota reservation, but it never gets decreased when the data actually gets written and overwrites the pre-existing data. So we're left with both the qgroup and qgroup reservation accounting for the same space. This commit adds the missing btrfs_qgroup_free_data() call in the case of BTRFS_ORDERED_PREALLOC extents. Fixes: c6887cd11149 ("Btrfs: don't do nocow check unless we have to") Signed-off-by: Justin Maggard Reviewed-by: Qu Wenruo Signed-off-by: David Sterba Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

dnotify: Handle errors from fsnotify_add_mark_locked() in fcntl_dirnotify()

2018-02-25T10:07:47Z

commit b3a0066005821acdc0cdb092cb72587182ab583f upstream. fsnotify_add_mark_locked() can fail but we do not check its return value. This didn't matter before commit 9dd813c15b2c "fsnotify: Move mark list head from object into dedicated structure" as none of possible failures could happen for dnotify but after that commit -ENOMEM can be returned. Handle this error properly in fcntl_dirnotify() as otherwise we just hit BUG_ON(dn_mark->dn) in dnotify_free_mark(). Reviewed-by: Amir Goldstein Reported-by: syzkaller Fixes: 9dd813c15b2c101168808d4f5941a29985758973 Signed-off-by: Jan Kara Signed-off-by: Greg Kroah-Hartman

ovl: hash directory inodes for fsnotify

2018-02-22T14:42:33Z

commit 31747eda41ef3c30c09c5c096b380bf54013746a upstream. fsnotify pins a watched directory inode in cache, but if directory dentry is released, new lookup will allocate a new dentry and a new inode. Directory events will be notified on the new inode, while fsnotify listener is watching the old pinned inode. Hash all directory inodes to reuse the pinned inode on lookup. Pure upper dirs are hashes by real upper inode, merge and lower dirs are hashed by real lower inode. The reference to lower inode was being held by the lower dentry object in the overlay dentry (oe->lowerstack[0]). Releasing the overlay dentry may drop lower inode refcount to zero. Add a refcount on behalf of the overlay inode to prevent that. As a by-product, hashing directory inodes also detects multiple redirected dirs to the same lower dir and uncovered redirected dir target on and returns -ESTALE on lookup. The reported issue dates back to initial version of overlayfs, but this patch depends on ovl_inode code that was introduced in kernel v4.13. Cc: #v4.13 Reported-by: Niklas Cassel Signed-off-by: Amir Goldstein Signed-off-by: Miklos Szeredi Tested-by: Niklas Cassel Signed-off-by: Greg Kroah-Hartman

Btrfs: fix unexpected -EEXIST when creating new inode

2018-02-22T14:42:30Z

commit 900c9981680067573671ecc5cbfa7c5770be3a40 upstream. The highest objectid, which is assigned to new inode, is decided at the time of initializing fs roots. However, in cases where log replay gets processed, the btree which fs root owns might be changed, so we have to search it again for the highest objectid, otherwise creating new inode would end up with -EEXIST. cc: v4.4-rc6+ Fixes: f32e48e92596 ("Btrfs: Initialize btrfs_root->highest_objectid when loading tree root and subvolume roots") Signed-off-by: Liu Bo Reviewed-by: Josef Bacik Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman

Btrfs: fix use-after-free on root->orphan_block_rsv

2018-02-22T14:42:30Z

commit 1a932ef4e47984dee227834667b5ff5a334e4805 upstream. I got these from running generic/475, WARNING: CPU: 0 PID: 26384 at fs/btrfs/inode.c:3326 btrfs_orphan_commit_root+0x1ac/0x2b0 [btrfs] BUG: unable to handle kernel NULL pointer dereference at 0000000000000010 IP: btrfs_block_rsv_release+0x1c/0x70 [btrfs] Call Trace: btrfs_orphan_release_metadata+0x9f/0x200 [btrfs] btrfs_orphan_del+0x10d/0x170 [btrfs] btrfs_setattr+0x500/0x640 [btrfs] notify_change+0x7ae/0x870 do_truncate+0xca/0x130 vfs_truncate+0x2ee/0x3d0 do_sys_truncate+0xaf/0xf0 SyS_truncate+0xe/0x10 entry_SYSCALL_64_fastpath+0x1f/0x96 The race is between btrfs_orphan_commit_root and btrfs_orphan_del, t1 t2 btrfs_orphan_commit_root btrfs_orphan_del spin_lock check (&root->orphan_inodes) root->orphan_block_rsv = NULL; spin_unlock atomic_dec(&root->orphan_inodes); access root->orphan_block_rsv Accessing root->orphan_block_rsv must be done before decreasing root->orphan_inodes. cc: v3.12+ Fixes: 703c88e03524 ("Btrfs: fix tracking of orphan inode count") Signed-off-by: Liu Bo Reviewed-by: Josef Bacik Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman

Btrfs: fix btrfs_evict_inode to handle abnormal inodes correctly

2018-02-22T14:42:30Z

commit e8f1bc1493855e32b7a2a019decc3c353d94daf6 upstream. This regression is introduced in commit 3d48d9810de4 ("btrfs: Handle uninitialised inode eviction"). There are two problems, a) it is ->destroy_inode() that does the final free on inode, not ->evict_inode(), b) clear_inode() must be called before ->evict_inode() returns. This could end up hitting BUG_ON(inode->i_state != (I_FREEING | I_CLEAR)); in evict() because I_CLEAR is set in clear_inode(). Fixes: commit 3d48d9810de4 ("btrfs: Handle uninitialised inode eviction") Cc: # v4.7-rc6+ Signed-off-by: Liu Bo Reviewed-by: Nikolay Borisov Reviewed-by: Josef Bacik Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman

Btrfs: fix extent state leak from tree log

2018-02-22T14:42:30Z

commit 55237a5f2431a72435e3ed39e4306e973c0446b7 upstream. It's possible that btrfs_sync_log() bails out after one of the two btrfs_write_marked_extents() which convert extent state's state bit into EXTENT_NEED_WAIT from EXTENT_DIRTY/EXTENT_NEW, however only EXTENT_DIRTY and EXTENT_NEW are searched by free_log_tree() so that those extent states with EXTENT_NEED_WAIT lead to memory leak. cc: Signed-off-by: Liu Bo Reviewed-by: Josef Bacik Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman

Btrfs: fix crash due to not cleaning up tree log block's dirty bits

2018-02-22T14:42:29Z

commit 1846430c24d66e85cc58286b3319c82cd54debb2 upstream. In cases that the whole fs flips into readonly status due to failures in critical sections, then log tree's blocks are still dirty, and this leads to a crash during umount time, the crash is about use-after-free, umount -> close_ctree -> stop workers -> iput(btree_inode) -> iput_final -> write_inode_now -> ... -> queue job on stop'd workers cc: v3.12+ Fixes: 681ae50917df ("Btrfs: cleanup reserved space when freeing tree log on error") Signed-off-by: Liu Bo Reviewed-by: Josef Bacik Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman