summaryrefslogtreecommitdiffstats
path: root/fs
Commit message (Collapse)AuthorAgeFilesLines
* Merge branch 'for-linus-4.7' of ↵Linus Torvalds2016-06-1811-43/+61
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull btrfs fixes from Chris Mason: "The most user visible change here is a fix for our recent superblock validation checks that were causing problems on non-4k pagesized systems" * 'for-linus-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: Btrfs: btrfs_check_super_valid: Allow 4096 as stripesize btrfs: remove build fixup for qgroup_account_snapshot btrfs: use new error message helper in qgroup_account_snapshot btrfs: avoid blocking open_ctree from cleaner_kthread Btrfs: don't BUG_ON() in btrfs_orphan_add btrfs: account for non-CoW'd blocks in btrfs_abort_transaction Btrfs: check if extent buffer is aligned to sectorsize btrfs: Use correct format specifier
| * Btrfs: btrfs_check_super_valid: Allow 4096 as stripesizeChandan Rajendra2016-06-171-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | Older btrfs-progs/mkfs.btrfs sets 4096 as the stripesize. Hence restricting stripesize to be equal to sectorsize would cause super block validation to return an error on architectures where PAGE_SIZE is not equal to 4096. Hence as a workaround, this commit allows stripesize to be set to 4096 bytes. Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * btrfs: remove build fixup for qgroup_account_snapshotDavid Sterba2016-06-171-5/+0
| | | | | | | | | | | | | | Introduced in 2c1984f244838477aab ("btrfs: build fixup for qgroup_account_snapshot") as temporary bisectability build fixup. Signed-off-by: David Sterba <dsterba@suse.com>
| * btrfs: use new error message helper in qgroup_account_snapshotDavid Sterba2016-06-171-1/+1
| | | | | | | | | | | | We've renamed btrfs_std_error, this one is left from last merge. Signed-off-by: David Sterba <dsterba@suse.com>
| * btrfs: avoid blocking open_ctree from cleaner_kthreadZygo Blaxell2016-06-172-15/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This fixes a problem introduced in commit 2f3165ecf103599f82bf0ea254039db335fb5005 "btrfs: don't force mounts to wait for cleaner_kthread to delete one or more subvolumes". open_ctree eventually calls btrfs_replay_log which in turn calls btrfs_commit_super which tries to lock the cleaner_mutex, causing a recursive mutex deadlock during mount. Instead of playing whack-a-mole trying to keep up with all the functions that may want to lock cleaner_mutex, put all the cleaner_mutex lockers back where they were, and attack the problem more directly: keep cleaner_kthread asleep until the filesystem is mounted. When filesystems are mounted read-only and later remounted read-write, open_ctree did not set fs_info->open and neither does anything else. Set this flag in btrfs_remount so that neither btrfs_delete_unused_bgs nor cleaner_kthread get confused by the common case of "/" filesystem read-only mount followed by read-write remount. Signed-off-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * Btrfs: don't BUG_ON() in btrfs_orphan_addJosef Bacik2016-06-171-1/+10
| | | | | | | | | | | | | | | | | | | | This is just a screwup for developers, so change it to an ASSERT() so developers notice when things go wrong and deal with the error appropriately if ASSERT() isn't enabled. Thanks, Signed-off-by: Josef Bacik <jbacik@fb.com> Reviewed-by: Mark Fasheh <mfasheh@suse.de> Signed-off-by: David Sterba <dsterba@suse.com>
| * btrfs: account for non-CoW'd blocks in btrfs_abort_transactionJeff Mahoney2016-06-174-4/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The test for !trans->blocks_used in btrfs_abort_transaction is insufficient to determine whether it's safe to drop the transaction handle on the floor. btrfs_cow_block, informed by should_cow_block, can return blocks that have already been CoW'd in the current transaction. trans->blocks_used is only incremented for new block allocations. If an operation overlaps the blocks in the current transaction entirely and must abort the transaction, we'll happily let it clean up the trans handle even though it may have modified the blocks and will commit an incomplete operation. In the long-term, I'd like to do closer tracking of when the fs is actually modified so we can still recover as gracefully as possible, but that approach will need some discussion. In the short term, since this is the only code using trans->blocks_used, let's just switch it to a bool indicating whether any blocks were used and set it when should_cow_block returns false. Cc: stable@vger.kernel.org # 3.4+ Signed-off-by: Jeff Mahoney <jeffm@suse.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * Btrfs: check if extent buffer is aligned to sectorsizeLiu Bo2016-06-176-15/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Thanks to fuzz testing, we can pass an invalid bytenr to extent buffer via alloc_extent_buffer(). An unaligned eb can have more pages than it should have, which ends up extent buffer's leak or some corrupted content in extent buffer. This adds a warning to let us quickly know what was happening. Now that alloc_extent_buffer() no more returns NULL, this changes its caller and callers of its caller to match with the new error handling. Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * btrfs: Use correct format specifierHeinrich Schuchardt2016-06-171-1/+1
| | | | | | | | | | | | | | | | | | Component mirror_num of struct btrfsic_block is defined as unsigned int. Use %u as format specifier. Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* | Merge tag 'nfsd-4.7-1' of git://linux-nfs.org/~bfields/linuxLinus Torvalds2016-06-164-49/+40
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull nfsd bugfixes from Bruce Fields: "Oleg Drokin found and fixed races in the nfsd4 state code that go back to the big nfs4_lock_state removal around 3.17 (but that were also probably hard to reproduce before client changes in 3.20 allowed the client to perform parallel opens). Also fix a 4.1 backchannel crash due to rpc multipath changes in 4.6. Trond acked the client-side rpc fixes going through my tree" * tag 'nfsd-4.7-1' of git://linux-nfs.org/~bfields/linux: nfsd: Make init_open_stateid() a bit more whole nfsd: Extend the mutex holding region around in nfsd4_process_open2() nfsd: Always lock state exclusively. rpc: share one xps between all backchannels nfsd4/rpc: move backchannel create logic into rpc code SUNRPC: fix xprt leak on xps allocation failure nfsd: Fix NFSD_MDS_PR_KEY on 32-bit by adding ULL postfix
| * | nfsd: Make init_open_stateid() a bit more wholeOleg Drokin2016-06-151-15/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | Move the state selection logic inside from the caller, always making it return correct stp to use. Signed-off-by: J . Bruce Fields <bfields@fieldses.org> Signed-off-by: Oleg Drokin <green@linuxhacker.ru> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
| * | nfsd: Extend the mutex holding region around in nfsd4_process_open2()Oleg Drokin2016-06-151-3/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | To avoid racing entry into nfs4_get_vfs_file(). Make init_open_stateid() return with locked stateid to be unlocked by the caller. Signed-off-by: Oleg Drokin <green@linuxhacker.ru> Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields <bfields@redhat.com>
| * | nfsd: Always lock state exclusively.Oleg Drokin2016-06-152-21/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It used to be the case that state had an rwlock that was locked for write by downgrades, but for read for upgrades (opens). Well, the problem is if there are two competing opens for the same state, they step on each other toes potentially leading to leaking file descriptors from the state structure, since access mode is a bitmap only set once. Signed-off-by: Oleg Drokin <green@linuxhacker.ru> Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields <bfields@redhat.com>
| * | nfsd4/rpc: move backchannel create logic into rpc codeJ. Bruce Fields2016-06-151-17/+1
| | | | | | | | | | | | | | | | | | | | | | | | Also simplify the logic a bit. Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields <bfields@redhat.com> Acked-by: Trond Myklebust <trondmy@primarydata.com>
| * | nfsd: Fix NFSD_MDS_PR_KEY on 32-bit by adding ULL postfixGeert Uytterhoeven2016-06-141-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On 32-bit: fs/nfsd/blocklayout.c: In function ‘nfsd4_block_get_device_info_scsi’: fs/nfsd/blocklayout.c:337: warning: integer constant is too large for ‘long’ type fs/nfsd/blocklayout.c:344: warning: integer constant is too large for ‘long’ type fs/nfsd/blocklayout.c: In function ‘nfsd4_scsi_fence_client’: fs/nfsd/blocklayout.c:385: warning: integer constant is too large for ‘long’ type Add the missing "ULL" postfix to 64-bit constant NFSD_MDS_PR_KEY to fix this. Fixes: f99d4fbdae6765d0 ("nfsd: add SCSI layout support") Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
* | | Merge branch 'overlayfs-linus' of ↵Linus Torvalds2016-06-162-22/+17
|\ \ \ | |/ / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs Pull overlayfs fixes from Miklos Szeredi: "This contains two regression fixes: one for the xattr API update and one for using the mounter's creds in file creation in overlayfs. There's also a fix for a bug in handling hard linked AF_UNIX sockets that's been there from day one. This fix is overlayfs only despite the fact that it touches code outside the overlay filesystem: d_real() is an identity function for all except overlay dentries" * 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs: ovl: fix uid/gid when creating over whiteout ovl: xattr filter fix af_unix: fix hard linked sockets on overlay vfs: add d_real_inode() helper
| * | ovl: fix uid/gid when creating over whiteoutMiklos Szeredi2016-06-151-2/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix a regression when creating a file over a whiteout. The new file/directory needs to use the current fsuid/fsgid, not the ones from the mounter's credentials. The refcounting is a bit tricky: prepare_creds() sets an original refcount, override_creds() gets one more, which revert_cred() drops. So 1) we need to expicitly put the mounter's credentials when overriding with the updated one 2) we need to put the original ref to the updated creds (and this can safely be done before revert_creds(), since we'll still have the ref from override_creds()). Reported-by: Stephen Smalley <sds@tycho.nsa.gov> Fixes: 3fe6e52f0626 ("ovl: override creds with the ones from the superblock mounter") Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * | ovl: xattr filter fixMiklos Szeredi2016-06-061-20/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | a) ovl_need_xattr_filter() is wrong, we can have multiple lower layers overlaid, all of which (except the lowest one) honouring the "trusted.overlay.opaque" xattr. So need to filter everything except the bottom and the pure-upper layer. b) we no longer can assume that inode is attached to dentry in get/setxattr. This patch unconditionally filters private xattrs to fix both of the above. Performance impact for get/removexattrs is likely in the noise. For listxattrs it might be measurable in pathological cases, but I very much hope nobody cares. If they do, we'll fix it then. Reported-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Fixes: b96809173e94 ("security_d_instantiate(): move to the point prior to attaching dentry to inode")
* | | Merge branch 'for-linus-4.7' of ↵Linus Torvalds2016-06-1018-357/+568
|\ \ \ | | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull btrfs fixes from Chris Mason: "Has some fixes and some new self tests for btrfs. The self tests are usually disabled in the .config file (unless you're doing btrfs dev work), and this bunch is meant to find problems with the 64K page size patches. Jeff has a patch to help people see if they are using the hardware assist crc32c module, which really helps us nail down problems when people ask why crcs are using so much CPU. Otherwise, it's small fixes" * 'for-linus-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: Btrfs: self-tests: Fix extent buffer bitmap test fail on BE system Btrfs: self-tests: Fix test_bitmaps fail on 64k sectorsize Btrfs: self-tests: Use macros instead of constants and add missing newline Btrfs: self-tests: Support testing all possible sectorsizes and nodesizes Btrfs: self-tests: Execute page straddling test only when nodesize < PAGE_SIZE btrfs: advertise which crc32c implementation is being used at module load Btrfs: add validadtion checks for chunk loading Btrfs: add more validation checks for superblock Btrfs: clear uptodate flags of pages in sys_array eb Btrfs: self-tests: Support non-4k page size Btrfs: Fix integer overflow when calculating bytes_per_bitmap Btrfs: test_check_exists: Fix infinite loop when searching for free space entries Btrfs: end transaction if we abort when creating uuid root btrfs: Use __u64 in exported linux/btrfs.h.
| * | Merge branch 'misc-fixes-4.7' of ↵Chris Mason2016-06-085-17/+114
| |\ \ | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.7
| | * | btrfs: advertise which crc32c implementation is being used at module loadJeff Mahoney2016-06-063-2/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since several architectures support hardware-accelerated crc32c calculation, it would be nice to confirm that btrfs is actually using it. We can see an elevated use count for the module, but it doesn't actually show who the users are. This patch simply prints the name of the driver after successfully initializing the shash. Signed-off-by: Jeff Mahoney <jeffm@suse.com> [ added a helper and used in module load-time message ] Signed-off-by: David Sterba <dsterba@suse.com>
| | * | Btrfs: add validadtion checks for chunk loadingLiu Bo2016-06-061-15/+67
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | To prevent fuzzed filesystem images from panic the whole system, we need various validation checks to refuse to mount such an image if btrfs finds any invalid value during loading chunks, including both sys_array and regular chunks. Note that these checks may not be sufficient to cover all corner cases, feel free to add more checks. Reported-by: Vegard Nossum <vegard.nossum@oracle.com> Reported-by: Quentin Casasnovas <quentin.casasnovas@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
| | * | Btrfs: add more validation checks for superblockLiu Bo2016-06-062-0/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds validation checks for super_total_bytes, super_bytes_used and super_stripesize, super_num_devices. Reported-by: Vegard Nossum <vegard.nossum@oracle.com> Reported-by: Quentin Casasnovas <quentin.casasnovas@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
| | * | Btrfs: clear uptodate flags of pages in sys_array ebLiu Bo2016-06-061-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We set uptodate flag to pages in the temporary sys_array eb, but do not clear the flag after free eb. As the special btree inode may still hold a reference on those pages, the uptodate flag can remain alive in them. If btrfs_super_chunk_root has been intentionally changed to the offset of this sys_array eb, reading chunk_root will read content of sys_array and it will skip our beautiful checks in btree_readpage_end_io_hook() because of "pages of eb are uptodate => eb is uptodate" This adds the 'clear uptodate' part to force it to read from disk. Reviewed-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
| | * | Btrfs: end transaction if we abort when creating uuid rootJosef Bacik2016-06-011-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We still need to call btrfs_end_transaction if we call btrfs_abort_transaction, otherwise we hang and make me super grumpy. Thanks, Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * | | Merge branch 'for-chris' of ↵Chris Mason2016-06-0815-340/+454
| |\ \ \ | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.7
| | * | | Btrfs: self-tests: Fix extent buffer bitmap test fail on BE systemFeifei Xu2016-06-061-1/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In __test_eb_bitmaps(), we write random data to a bitmap. Then copy the bitmap to another bitmap that resides inside an extent buffer. Later we verify the values of corresponding bits in the bitmap and the bitmap inside the extent buffer. However, extent_buffer_test_bit() reads in byte granularity while test_bit() reads in unsigned long granularity. Hence we end up comparing wrong bits on big-endian systems such as ppc64. This commit fixes the issue by reading the bitmap in byte granularity. Reviewed-by: Josef Bacik <jbacik@fb.com> Reviewed-by: Chandan Rajendra <chandan@linux.vnet.ibm.com> Signed-off-by: Feifei Xu <xufeifei@linux.vnet.ibm.com> Signed-off-by: David Sterba <dsterba@suse.com>
| | * | | Btrfs: self-tests: Fix test_bitmaps fail on 64k sectorsizeFeifei Xu2016-06-061-1/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With 64K sectorsize, 1G sized block group cannot span across bitmaps. To execute test_bitmaps() function, this commit allocates "BITS_PER_BITMAP * sectorsize + PAGE_SIZE" sized block group. Reviewed-by: Josef Bacik <jbacik@fb.com> Reviewed-by: Chandan Rajendra <chandan@linux.vnet.ibm.com> Signed-off-by: Feifei Xu <xufeifei@linux.vnet.ibm.com> Signed-off-by: David Sterba <dsterba@suse.com>
| | * | | Btrfs: self-tests: Use macros instead of constants and add missing newlineFeifei Xu2016-06-063-18/+31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This commit replaces numerical constants with appropriate preprocessor macros. Reviewed-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com> Signed-off-by: Feifei Xu <xufeifei@linux.vnet.ibm.com> Signed-off-by: David Sterba <dsterba@suse.com>
| | * | | Btrfs: self-tests: Support testing all possible sectorsizes and nodesizesFeifei Xu2016-06-061-22/+32
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | To test all possible sectorsizes, this commit adds a sectorsize array. This commit executes the tests for all possible sectorsizes and nodesizes. Reviewed-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com> Signed-off-by: Feifei Xu <xufeifei@linux.vnet.ibm.com> Signed-off-by: David Sterba <dsterba@suse.com>
| | * | | Btrfs: self-tests: Execute page straddling test only when nodesize < PAGE_SIZEFeifei Xu2016-06-061-19/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On ppc64, PAGE_SIZE is 64k which is same as BTRFS_MAX_METADATA_BLOCKSIZE. In such a scenario, we will never be able to have an extent buffer containing more than one page. Hence in such cases this commit does not execute the page straddling tests. Reviewed-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Feifei Xu <xufeifei@linux.vnet.ibm.com> Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com> Signed-off-by: David Sterba <dsterba@suse.com>
| | * | | Btrfs: self-tests: Support non-4k page sizeFeifei Xu2016-06-0215-291/+355
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | self-tests code assumes 4k as the sectorsize and nodesize. This commit fix hardcoded 4K. Enables the self-tests code to be executed on non-4k page sized systems (e.g. ppc64). Reviewed-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Feifei Xu <xufeifei@linux.vnet.ibm.com> Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com> Signed-off-by: David Sterba <dsterba@suse.com>
| | * | | Btrfs: Fix integer overflow when calculating bytes_per_bitmapFeifei Xu2016-06-022-7/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On ppc64, bytes_per_bitmap will be (65536*8*65536). Hence append UL to fix integer overflow. Reviewed-by: Josef Bacik <jbacik@fb.com> Reviewed-by: Chandan Rajendra <chandan@linux.vnet.ibm.com> Signed-off-by: Feifei Xu <xufeifei@linux.vnet.ibm.com> Signed-off-by: David Sterba <dsterba@suse.com>
| | * | | Btrfs: test_check_exists: Fix infinite loop when searching for free space ↵Feifei Xu2016-06-021-2/+2
| | |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | entries On a ppc64 machine using 64K as the block size, assume that the RB tree at btrfs_free_space_ctl->free_space_offset contains following two entries: 1. A bitmap entry having an offset value of 0 and having the bits corresponding to the address range [128M+512K, 128M+768K] set. 2. An extent entry corresponding to the address range [128M-256K, 128M-128K] In such a scenario, test_check_exists() invoked for checking the existence of address range [128M+768K, 256M] can lead to an infinite loop as explained below: - Checking for the extent entry fails. - Checking for a bitmap entry results in the free space info in range [128M+512K, 128M+768K] beng returned. - rb_prev(info) returns NULL because the bitmap entry starting from offset 0 comes first in the RB tree. - current_node = bitmap node. - while (current_node) tmp = rb_next(bitmap_node);/*tmp is extent based free space entry*/ Since extent based free space entry's last address is smaller than the address being searched for (i.e. 128M+768K) we incorrectly again obtain the extent node as the "next right node" of the RB tree and thus end up looping infinitely. This patch fixes the issue by checking the "tmp" variable which point to the most recently searched free space node. Reviewed-by: Josef Bacik <jbacik@fb.com> Reviewed-by: Chandan Rajendra <chandan@linux.vnet.ibm.com> Signed-off-by: Feifei Xu <xufeifei@linux.vnet.ibm.com> Signed-off-by: David Sterba <dsterba@suse.com>
* | | | Merge branch 'stacking-fixes' (vfs stacking fixes from Jann)Linus Torvalds2016-06-102-2/+18
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge filesystem stacking fixes from Jann Horn. * emailed patches from Jann Horn <jannh@google.com>: sched: panic on corrupted stack end ecryptfs: forbid opening files without mmap handler proc: prevent stacking filesystems on top
| * | | | ecryptfs: forbid opening files without mmap handlerJann Horn2016-06-101-2/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This prevents users from triggering a stack overflow through a recursive invocation of pagefault handling that involves mapping procfs files into virtual memory. Signed-off-by: Jann Horn <jannh@google.com> Acked-by: Tyler Hicks <tyhicks@canonical.com> Cc: stable@vger.kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | proc: prevent stacking filesystems on topJann Horn2016-06-101-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This prevents stacking filesystems (ecryptfs and overlayfs) from using procfs as lower filesystem. There is too much magic going on inside procfs, and there is no good reason to stack stuff on top of procfs. (For example, procfs does access checks in VFS open handlers, and ecryptfs by design calls open handlers from a kernel thread that doesn't drop privileges or so.) Signed-off-by: Jann Horn <jannh@google.com> Cc: stable@vger.kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | | | Merge branch 'for-linus' of ↵Linus Torvalds2016-06-075-51/+22
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs fixes from Al Viro: "Fixes for crap of assorted ages: EOPENSTALE one is 4.2+, autofs one is 4.6, d_walk - 3.2+. The atomic_open() and coredump ones are regressions from this window" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: coredump: fix dumping through pipes fix a regression in atomic_open() fix d_walk()/non-delayed __d_free() race autofs braino fix for do_last() fix EOPENSTALE bug in do_last()
| * | | | | coredump: fix dumping through pipesMateusz Guzik2016-06-073-3/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The offset in the core file used to be tracked with ->written field of the coredump_params structure. The field was retired in favour of file->f_pos. However, ->f_pos is not maintained for pipes which leads to breakage. Restore explicit tracking of the offset in coredump_params. Introduce ->pos field for this purpose since ->written was already reused. Fixes: a00839395103 ("get rid of coredump_params->written"). Reported-by: Zbigniew Jędrzejewski-Szmek <zbyszek@in.waw.pl> Signed-off-by: Mateusz Guzik <mguzik@redhat.com> Reviewed-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * | | | | fix a regression in atomic_open()Al Viro2016-06-071-3/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | open("/foo/no_such_file", O_RDONLY | O_CREAT) on should fail with EACCES when /foo is not writable; failing with ENOENT is obviously wrong. That got broken by a braino introduced when moving the creat_error logics from atomic_open() to lookup_open(). Easy to fix, fortunately. Spotted-by: "Yan, Zheng" <ukernel@gmail.com> Tested-by: "Yan, Zheng" <ukernel@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * | | | | fix d_walk()/non-delayed __d_free() raceAl Viro2016-06-071-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Ascend-to-parent logics in d_walk() depends on all encountered child dentries not getting freed without an RCU delay. Unfortunately, in quite a few cases it is not true, with hard-to-hit oopsable race as the result. Fortunately, the fix is simiple; right now the rule is "if it ever been hashed, freeing must be delayed" and changing it to "if it ever had a parent, freeing must be delayed" closes that hole and covers all cases the old rule used to cover. Moreover, pipes and sockets remain _not_ covered, so we do not introduce RCU delay in the cases which are the reason for having that delay conditional in the first place. Cc: stable@vger.kernel.org # v3.2+ (and watch out for __d_materialise_dentry()) Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * | | | | autofs braino fix for do_last()Al Viro2016-06-051-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It's an analogue of commit 7500c38a (fix the braino in "namei: massage lookup_slow() to be usable by lookup_one_len_unlocked()"). The same problem (->lookup()-returned unhashed negative dentry just might be an autofs one with ->d_manage() that would wait until the daemon makes it positive) applies in do_last() - we need to do follow_managed() first. Fortunately, remaining callers of follow_managed() are OK - only autofs has that weirdness (negative dentry that does not mean an instant -ENOENT)) and autofs never has its negative dentries hashed, so we can't pick one from a dcache lookup. ->d_manage() is a bloody mess ;-/ Cc: stable@vger.kernel.org # v4.6 Spotted-by: Ian Kent <raven@themaw.net> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * | | | | fix EOPENSTALE bug in do_last()Al Viro2016-06-041-39/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | EOPENSTALE occuring at the last component of a trailing symlink ends up with do_last() retrying its lookup. After the symlink body has been discarded. The thing is, all this retry_lookup logics in there is not needed at all - the upper layers will do the right thing if we simply return that -EOPENSTALE as we would with any other error. Trying to microoptimize in do_last() is a lot of headache for no good reason. Cc: stable@vger.kernel.org # v4.2+ Tested-by: Oleg Drokin <green@linuxhacker.ru> Reviewed-and-Tested-by: Jeff Layton <jlayton@poochiereds.net> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | | | | | mnt: fs_fully_visible test the proper mount for MNT_LOCKEDEric W. Biederman2016-06-061-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | MNT_LOCKED implies on a child mount implies the child is locked to the parent. So while looping through the children the children should be tested (not their parent). Typically an unshare of a mount namespace locks all mounts together making both the parent and the slave as locked but there are a few corner cases where other things work. Cc: stable@vger.kernel.org Fixes: ceeb0e5d39fc ("vfs: Ignore unlocked mounts in fs_fully_visible") Reported-by: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
* | | | | | mnt: If fs_fully_visible fails call put_filesystem.Eric W. Biederman2016-06-061-1/+3
| |_|_|_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add this trivial missing error handling. Cc: stable@vger.kernel.org Fixes: 1b852bceb0d1 ("mnt: Refactor the logic for mounting sysfs and proc in a user namespace") Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
* | | | | devpts: Make each mount of devpts an independent filesystem.Eric W. Biederman2016-06-052-143/+97
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The /dev/ptmx device node is changed to lookup the directory entry "pts" in the same directory as the /dev/ptmx device node was opened in. If there is a "pts" entry and that entry is a devpts filesystem /dev/ptmx uses that filesystem. Otherwise the open of /dev/ptmx fails. The DEVPTS_MULTIPLE_INSTANCES configuration option is removed, so that userspace can now safely depend on each mount of devpts creating a new instance of the filesystem. Each mount of devpts is now a separate and equal filesystem. Reserved ttys are now available to all instances of devpts where the mounter is in the initial mount namespace. A new vfs helper path_pts is introduced that finds a directory entry named "pts" in the directory of the passed in path, and changes the passed in path to point to it. The helper path_pts uses a function path_parent_directory that was factored out of follow_dotdot. In the implementation of devpts: - devpts_mnt is killed as it is no longer meaningful if all mounts of devpts are equal. - pts_sb_from_inode is replaced by just inode->i_sb as all cached inodes in the tty layer are now from the devpts filesystem. - devpts_add_ref is rolled into the new function devpts_ptmx. And the unnecessary inode hold is removed. - devpts_del_ref is renamed devpts_release and reduced to just a deacrivate_super. - The newinstance mount option continues to be accepted but is now ignored. In devpts_fs.h definitions for when !CONFIG_UNIX98_PTYS are removed as they are never used. Documentation/filesystems/devices.txt is updated to describe the current situation. This has been verified to work properly on openwrt-15.05, centos5, centos6, centos7, debian-6.0.2, debian-7.9, debian-8.2, ubuntu-14.04.3, ubuntu-15.10, fedora23, magia-5, mint-17.3, opensuse-42.1, slackware-14.1, gentoo-20151225 (13.0?), archlinux-2015-12-01. With the caveat that on centos6 and on slackware-14.1 that there wind up being two instances of the devpts filesystem mounted on /dev/pts, the lower copy does not end up getting used. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Greg KH <greg@kroah.com> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Serge Hallyn <serge.hallyn@ubuntu.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk> Cc: Jann Horn <jann@thejh.net> Cc: Jiri Slaby <jslaby@suse.com> Cc: Florian Weimer <fw@deneb.enyo.de> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | | | Merge branch 'for-linus-4.7' of ↵Linus Torvalds2016-06-048-18/+103
|\ \ \ \ \ | | |_|/ / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull btrfs fixes from Chris Mason: "The important part of this pull is Filipe's set of fixes for btrfs device replacement. Filipe fixed a few issues seen on the list and a number he found on his own" * 'for-linus-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: Btrfs: deal with duplciates during extent_map insertion in btrfs_get_extent Btrfs: fix race between device replace and read repair Btrfs: fix race between device replace and discard Btrfs: fix race between device replace and chunk allocation Btrfs: fix race setting block group back to RW mode during device replace Btrfs: fix unprotected assignment of the left cursor for device replace Btrfs: fix race setting block group readonly during device replace Btrfs: fix race between device replace and block group removal Btrfs: fix race between readahead and device replace/removal
| * | | | Btrfs: deal with duplciates during extent_map insertion in btrfs_get_extentChris Mason2016-06-031-1/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When dealing with inline extents, btrfs_get_extent will incorrectly try to insert a duplicate extent_map. The dup hits -EEXIST from add_extent_map, but then we try to merge with the existing one and end up trying to insert a zero length extent_map. This actually works most of the time, except when there are extent maps past the end of the inline extent. rocksdb will trigger this sometimes because it preallocates an extent and then truncates down. Josef made a script to trigger with xfs_io: #!/bin/bash xfs_io -f -c "pwrite 0 1000" inline xfs_io -c "falloc -k 4k 1M" inline xfs_io -c "pread 0 1000" -c "fadvise -d 0 1000" -c "pread 0 1000" inline xfs_io -c "fadvise -d 0 1000" inline cat inline You'll get EIOs trying to read inline after this because add_extent_map is returning EEXIST Signed-off-by: Chris Mason <clm@fb.com>
| * | | | Btrfs: fix race between device replace and read repairFilipe Manana2016-05-311-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While we are finishing a device replace operation we can have a concurrent task trying to do a read repair operation, in which case it will call btrfs_map_block() to get a struct btrfs_bio which can have a stripe that points to the source device of the device replace operation. This allows for the read repair task to dereference the stripe's device pointer after the device replace operation has freed the source device, resulting in an invalid memory access. This is similar to the problem solved by my previous patch in the same series and named "Btrfs: fix race between device replace and discard". So fix this by surrounding the call to btrfs_map_block() and the code that uses the returned struct btrfs_bio with calls to btrfs_bio_counter_inc_blocked() and btrfs_bio_counter_dec(), giving the proper serialization with the finishing phase of the device replace operation. Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: Josef Bacik <jbacik@fb.com>
| * | | | Btrfs: fix race between device replace and discardFilipe Manana2016-05-311-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While we are finishing a device replace operation, we can make a discard operation (fs mounted with -o discard) do an invalid memory access like the one reported by the following trace: [ 3206.384654] general protection fault: 0000 [#1] PREEMPT SMP [ 3206.387520] Modules linked in: dm_mod btrfs crc32c_generic xor raid6_pq acpi_cpufreq tpm_tis psmouse tpm ppdev sg parport_pc evdev i2c_piix4 parport processor serio_raw i2c_core pcspkr button loop autofs4 ext4 crc16 jbd2 mbcache sr_mod cdrom ata_generic sd_mod virtio_scsi ata_piix libata virtio_pci virtio_ring scsi_mod e1000 virtio floppy [last unloaded: btrfs] [ 3206.388595] CPU: 14 PID: 29194 Comm: fsstress Not tainted 4.6.0-rc7-btrfs-next-29+ #1 [ 3206.388595] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS by qemu-project.org 04/01/2014 [ 3206.388595] task: ffff88017ace0100 ti: ffff880171b98000 task.ti: ffff880171b98000 [ 3206.388595] RIP: 0010:[<ffffffff8124d233>] [<ffffffff8124d233>] blkdev_issue_discard+0x5c/0x2a7 [ 3206.388595] RSP: 0018:ffff880171b9bb80 EFLAGS: 00010246 [ 3206.388595] RAX: ffff880171b9bc28 RBX: 000000000090d000 RCX: 0000000000000000 [ 3206.388595] RDX: ffffffff82fa1b48 RSI: ffffffff8179f46c RDI: ffffffff82fa1b48 [ 3206.388595] RBP: ffff880171b9bcc0 R08: 0000000000000000 R09: 0000000000000001 [ 3206.388595] R10: ffff880171b9bce0 R11: 000000000090f000 R12: ffff880171b9bbe8 [ 3206.388595] R13: 0000000000000010 R14: 0000000000004868 R15: 6b6b6b6b6b6b6b6b [ 3206.388595] FS: 00007f6182e4e700(0000) GS:ffff88023fdc0000(0000) knlGS:0000000000000000 [ 3206.388595] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 3206.388595] CR2: 00007f617c2bbb18 CR3: 000000017ad9c000 CR4: 00000000000006e0 [ 3206.388595] Stack: [ 3206.388595] 0000000000004878 0000000000000000 0000000002400040 0000000000000000 [ 3206.388595] 0000000000000000 ffff880171b9bbe8 ffff880171b9bbb0 ffff880171b9bbb0 [ 3206.388595] ffff880171b9bbc0 ffff880171b9bbc0 ffff880171b9bbd0 ffff880171b9bbd0 [ 3206.388595] Call Trace: [ 3206.388595] [<ffffffffa042899e>] btrfs_issue_discard+0x12f/0x143 [btrfs] [ 3206.388595] [<ffffffffa042899e>] ? btrfs_issue_discard+0x12f/0x143 [btrfs] [ 3206.388595] [<ffffffffa042e862>] btrfs_discard_extent+0x87/0xde [btrfs] [ 3206.388595] [<ffffffffa04303b5>] btrfs_finish_extent_commit+0xb2/0x1df [btrfs] [ 3206.388595] [<ffffffff8149c246>] ? __mutex_unlock_slowpath+0x150/0x15b [ 3206.388595] [<ffffffffa04464c4>] btrfs_commit_transaction+0x7fc/0x980 [btrfs] [ 3206.388595] [<ffffffff8149c246>] ? __mutex_unlock_slowpath+0x150/0x15b [ 3206.388595] [<ffffffffa0459af6>] btrfs_sync_file+0x38f/0x428 [btrfs] [ 3206.388595] [<ffffffff811a8292>] vfs_fsync_range+0x8c/0x9e [ 3206.388595] [<ffffffff811a82c0>] vfs_fsync+0x1c/0x1e [ 3206.388595] [<ffffffff811a8417>] do_fsync+0x31/0x4a [ 3206.388595] [<ffffffff811a8637>] SyS_fsync+0x10/0x14 [ 3206.388595] [<ffffffff8149e025>] entry_SYSCALL_64_fastpath+0x18/0xa8 [ 3206.388595] [<ffffffff81100c6b>] ? time_hardirqs_off+0x9/0x14 [ 3206.388595] [<ffffffff8108e87d>] ? trace_hardirqs_off_caller+0x1f/0xaa This happens because when we call btrfs_map_block() from btrfs_discard_extent() to get a btrfs_bio structure, the device replace operation has not finished yet, but before we use the device of one of the stripes from the returned btrfs_bio structure, the device object is freed. This is illustrated by the following diagram. CPU 1 CPU 2 btrfs_dev_replace_start() (...) btrfs_dev_replace_finishing() btrfs_start_transaction() btrfs_commit_transaction() (...) btrfs_sync_file() btrfs_start_transaction() (...) btrfs_commit_transaction() btrfs_finish_extent_commit() btrfs_discard_extent() btrfs_map_block() --> returns a struct btrfs_bio with a stripe that has a device field pointing to source device of the replace operation (the device that is being replaced) mutex_lock(&uuid_mutex) mutex_lock(&fs_info->fs_devices->device_list_mutex) mutex_lock(&fs_info->chunk_mutex) btrfs_dev_replace_update_device_in_mapping_tree() --> iterates the mapping tree and for each extent map that has a stripe pointing to the source device, it updates the stripe to point to the target device instead btrfs_rm_dev_replace_blocked() --> waits for fs_info->bio_counter to go down to 0 btrfs_rm_dev_replace_remove_srcdev() --> removes source device from the list of devices mutex_unlock(&fs_info->chunk_mutex) mutex_unlock(&fs_info->fs_devices->device_list_mutex) mutex_unlock(&uuid_mutex) btrfs_rm_dev_replace_free_srcdev() --> frees the source device --> iterates over all stripes of the returned struct btrfs_bio --> for each stripe it dereferences its device pointer --> it ends up finding a pointer to the device used as the source device for the replace operation and that was already freed So fix this by surrounding the call to btrfs_map_block(), and the code that uses the returned struct btrfs_bio, with calls to btrfs_bio_counter_inc_blocked() and btrfs_bio_counter_dec(), so that the finishing phase of the device replace operation blocks until the the bio counter decreases to zero before it frees the source device. This is the same approach we do at btrfs_map_bio() for example. Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: Josef Bacik <jbacik@fb.com>
OpenPOWER on IntegriCloud