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2014-09-17xfs: quotacheck leaves dquot buffers without verifiersDave Chinner
commit 5fd364fee81a7888af806e42ed8a91c845894f2d upstream. When running xfs/305, I noticed that quotacheck was flushing dquot buffers that did not have the xfs_dquot_buf_ops verifiers attached: XFS (vdb): _xfs_buf_ioapply: no ops on block 0x1dc8/0x1dc8 ffff880052489000: 44 51 01 04 00 00 65 b8 00 00 00 00 00 00 00 00 DQ....e......... ffff880052489010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ ffff880052489020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ ffff880052489030: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ CPU: 1 PID: 2376 Comm: mount Not tainted 3.16.0-rc2-dgc+ #306 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 ffff88006fe38000 ffff88004a0ffae8 ffffffff81cf1cca 0000000000000001 ffff88004a0ffb88 ffffffff814d50ca 000010004a0ffc70 0000000000000000 ffff88006be56dc4 0000000000000021 0000000000001dc8 ffff88007c773d80 Call Trace: [<ffffffff81cf1cca>] dump_stack+0x45/0x56 [<ffffffff814d50ca>] _xfs_buf_ioapply+0x3ca/0x3d0 [<ffffffff810db520>] ? wake_up_state+0x20/0x20 [<ffffffff814d51f5>] ? xfs_bdstrat_cb+0x55/0xb0 [<ffffffff814d513b>] xfs_buf_iorequest+0x6b/0xd0 [<ffffffff814d51f5>] xfs_bdstrat_cb+0x55/0xb0 [<ffffffff814d53ab>] __xfs_buf_delwri_submit+0x15b/0x220 [<ffffffff814d6040>] ? xfs_buf_delwri_submit+0x30/0x90 [<ffffffff814d6040>] xfs_buf_delwri_submit+0x30/0x90 [<ffffffff8150f89d>] xfs_qm_quotacheck+0x17d/0x3c0 [<ffffffff81510591>] xfs_qm_mount_quotas+0x151/0x1e0 [<ffffffff814ed01c>] xfs_mountfs+0x56c/0x7d0 [<ffffffff814f0f12>] xfs_fs_fill_super+0x2c2/0x340 [<ffffffff811c9fe4>] mount_bdev+0x194/0x1d0 [<ffffffff814f0c50>] ? xfs_finish_flags+0x170/0x170 [<ffffffff814ef0f5>] xfs_fs_mount+0x15/0x20 [<ffffffff811ca8c9>] mount_fs+0x39/0x1b0 [<ffffffff811e4d67>] vfs_kern_mount+0x67/0x120 [<ffffffff811e757e>] do_mount+0x23e/0xad0 [<ffffffff8117abde>] ? __get_free_pages+0xe/0x50 [<ffffffff811e71e6>] ? copy_mount_options+0x36/0x150 [<ffffffff811e8103>] SyS_mount+0x83/0xc0 [<ffffffff81cfd40b>] tracesys+0xdd/0xe2 This was caused by dquot buffer readahead not attaching a verifier structure to the buffer when readahead was issued, resulting in the followup read of the buffer finding a valid buffer and so not attaching new verifiers to the buffer as part of the read. Also, when a verifier failure occurs, we then read the buffer without verifiers. Attach the verifiers manually after this read so that if the buffer is then written it will be verified that the corruption has been repaired. Further, when flushing a dquot we don't ask for a verifier when reading in the dquot buffer the dquot belongs to. Most of the time this isn't an issue because the buffer is still cached, but when it is not cached it will result in writing the dquot buffer without having the verfier attached. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Chinner <david@fromorbit.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-17xfs: ensure verifiers are attached to recovered buffersDave Chinner
commit 67dc288c21064b31a98a53dc64f6b9714b819fd6 upstream. Crash testing of CRC enabled filesystems has resulted in a number of reports of bad CRCs being detected after the filesystem was mounted. Errors such as the following were being seen: XFS (sdb3): Mounting V5 Filesystem XFS (sdb3): Starting recovery (logdev: internal) XFS (sdb3): Metadata CRC error detected at xfs_agf_read_verify+0x5a/0x100 [xfs], block 0x1 XFS (sdb3): Unmount and run xfs_repair XFS (sdb3): First 64 bytes of corrupted metadata buffer: ffff880136ffd600: 58 41 47 46 00 00 00 01 00 00 00 00 00 0f aa 40 XAGF...........@ ffff880136ffd610: 00 02 6d 53 00 02 77 f8 00 00 00 00 00 00 00 01 ..mS..w......... ffff880136ffd620: 00 00 00 01 00 00 00 00 00 00 00 00 00 00 00 03 ................ ffff880136ffd630: 00 00 00 04 00 08 81 d0 00 08 81 a7 00 00 00 00 ................ XFS (sdb3): metadata I/O error: block 0x1 ("xfs_trans_read_buf_map") error 74 numblks 1 The errors were typically being seen in AGF, AGI and their related btree block buffers some time after log recovery had run. Often it wasn't until later subsequent mounts that the problem was discovered. The common symptom was a buffer with the correct contents, but a CRC and an LSN that matched an older version of the contents. Some debug added to _xfs_buf_ioapply() indicated that buffers were being written without verifiers attached to them from log recovery, and Jan Kara isolated the cause to log recovery readahead an dit's interactions with buffers that had a more recent LSN on disk than the transaction being recovered. In this case, the buffer did not get a verifier attached, and os when the second phase of log recovery ran and recovered EFIs and unlinked inodes, the buffers were modified and written without the verifier running. Hence they had up to date contents, but stale LSNs and CRCs. Fix it by attaching verifiers to buffers we skip due to future LSN values so they don't escape into the buffer cache without the correct verifier attached. This patch is based on analysis and a patch from Jan Kara. Reported-by: Jan Kara <jack@suse.cz> Reported-by: Fanael Linithien <fanael4@gmail.com> Reported-by: Grozdan <neutrino8@gmail.com> Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Chinner <david@fromorbit.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-17fix copy_tree() regressionAl Viro
commit 12a5b5294cb1896e9a3c9fca8ff5a7e3def4e8c6 upstream. Since 3.14 we had copy_tree() get the shadowing wrong - if we had one vfsmount shadowing another (i.e. if A is a slave of B, C is mounted on A/foo, then D got mounted on B/foo creating D' on A/foo shadowed by C), copy_tree() of A would make a copy of D' shadow the the copy of C, not the other way around. It's easy to fix, fortunately - just make sure that mount follows the one that shadows it in mnt_child as well as in mnt_hash, and when copy_tree() decides to attach a new mount, check if the last child it has added to the same parent should be shadowing the new one. And if it should, just use the same logics commit_tree() has - put the new mount into the hash and children lists right after the one that should shadow it. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-17fix EBUSY on umount() from MNT_SHRINKABLEAl Viro
commit 81b6b06197606b4bef4e427a197aeb808e8d89e1 upstream. We need the parents of victims alive until namespace_unlock() gets to dput() of the (ex-)mountpoints. However, that screws up the "is it busy" checks in case when we have shrinkable mounts that need to be killed. Solution: go ahead and decrement refcounts of parents right in umount_tree(), increment them again just before dropping rwsem in namespace_unlock() (and let the loop in the end of namespace_unlock() finally drop those references for good, as we do now). Parents can't get freed until we drop rwsem - at least one reference is kept until then, both in case when parent is among the victims and when it is not. So they'll still be around when we get to namespace_unlock(). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-17get rid of propagate_umount() mistakenly treating slaves as busy.Al Viro
commit 88b368f27a094277143d8ecd5a056116f6a41520 upstream. The check in __propagate_umount() ("has somebody explicitly mounted something on that slave?") is done *before* taking the already doomed victims out of the child lists. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-17mnt: Change the default remount atime from relatime to the existing valueEric W. Biederman
commit ffbc6f0ead47fa5a1dc9642b0331cb75c20a640e upstream. Since March 2009 the kernel has treated the state that if no MS_..ATIME flags are passed then the kernel defaults to relatime. Defaulting to relatime instead of the existing atime state during a remount is silly, and causes problems in practice for people who don't specify any MS_...ATIME flags and to get the default filesystem atime setting. Those users may encounter a permission error because the default atime setting does not work. A default that does not work and causes permission problems is ridiculous, so preserve the existing value to have a default atime setting that is always guaranteed to work. Using the default atime setting in this way is particularly interesting for applications built to run in restricted userspace environments without /proc mounted, as the existing atime mount options of a filesystem can not be read from /proc/mounts. In practice this fixes user space that uses the default atime setting on remount that are broken by the permission checks keeping less privileged users from changing more privileged users atime settings. Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-17mnt: Correct permission checks in do_remountEric W. Biederman
commit 9566d6742852c527bf5af38af5cbb878dad75705 upstream. While invesgiating the issue where in "mount --bind -oremount,ro ..." would result in later "mount --bind -oremount,rw" succeeding even if the mount started off locked I realized that there are several additional mount flags that should be locked and are not. In particular MNT_NOSUID, MNT_NODEV, MNT_NOEXEC, and the atime flags in addition to MNT_READONLY should all be locked. These flags are all per superblock, can all be changed with MS_BIND, and should not be changable if set by a more privileged user. The following additions to the current logic are added in this patch. - nosuid may not be clearable by a less privileged user. - nodev may not be clearable by a less privielged user. - noexec may not be clearable by a less privileged user. - atime flags may not be changeable by a less privileged user. The logic with atime is that always setting atime on access is a global policy and backup software and auditing software could break if atime bits are not updated (when they are configured to be updated), and serious performance degradation could result (DOS attack) if atime updates happen when they have been explicitly disabled. Therefore an unprivileged user should not be able to mess with the atime bits set by a more privileged user. The additional restrictions are implemented with the addition of MNT_LOCK_NOSUID, MNT_LOCK_NODEV, MNT_LOCK_NOEXEC, and MNT_LOCK_ATIME mnt flags. Taken together these changes and the fixes for MNT_LOCK_READONLY should make it safe for an unprivileged user to create a user namespace and to call "mount --bind -o remount,... ..." without the danger of mount flags being changed maliciously. Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-17mnt: Move the test for MNT_LOCK_READONLY from change_mount_flags into do_remountEric W. Biederman
commit 07b645589dcda8b7a5249e096fece2a67556f0f4 upstream. There are no races as locked mount flags are guaranteed to never change. Moving the test into do_remount makes it more visible, and ensures all filesystem remounts pass the MNT_LOCK_READONLY permission check. This second case is not an issue today as filesystem remounts are guarded by capable(CAP_DAC_ADMIN) and thus will always fail in less privileged mount namespaces, but it could become an issue in the future. Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-17mnt: Only change user settable mount flags in remountEric W. Biederman
commit a6138db815df5ee542d848318e5dae681590fccd upstream. Kenton Varda <kenton@sandstorm.io> discovered that by remounting a read-only bind mount read-only in a user namespace the MNT_LOCK_READONLY bit would be cleared, allowing an unprivileged user to the remount a read-only mount read-write. Correct this by replacing the mask of mount flags to preserve with a mask of mount flags that may be changed, and preserve all others. This ensures that any future bugs with this mask and remount will fail in an easy to detect way where new mount flags simply won't change. Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-17ocfs2: do not write error flag to user structure we cannot copy from/toBen Hutchings
commit 2b462638e41ea62230297c21c4da9955937b7a3c upstream. If we failed to copy from the structure, writing back the flags leaks 31 bits of kernel memory (the rest of the ir_flags field). In any case, if we cannot copy from/to the structure, why should we expect putting just the flags to work? Also make sure ocfs2_info_handle_freeinode() returns the right error code if the copy_to_user() fails. Fixes: ddee5cdb70e6 ('Ocfs2: Add new OCFS2_IOC_INFO ioctl for ocfs2 v8.') Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Cc: Joel Becker <jlbec@evilplan.org> Acked-by: Mark Fasheh <mfasheh@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-17fanotify: fix double free of pending permission eventsJan Kara
commit 5838d4442bd5971687b72221736222637e03140d upstream. Commit 85816794240b ("fanotify: Fix use after free for permission events") introduced a double free issue for permission events which are pending in group's notification queue while group is being destroyed. These events are freed from fanotify_handle_event() but they are not removed from groups notification queue and thus they get freed again from fsnotify_flush_notify(). Fix the problem by removing permission events from notification queue before freeing them if we skip processing access response. Also expand comments in fanotify_release() to explain group shutdown in detail. Fixes: 85816794240b9659e66e4d9b0df7c6e814e5f603 Signed-off-by: Jan Kara <jack@suse.cz> Reported-by: Douglas Leeder <douglas.leeder@sophos.com> Tested-by: Douglas Leeder <douglas.leeder@sophos.com> Reported-by: Heinrich Schuchard <xypron.glpk@gmx.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-17CAPABILITIES: remove undefined caps from all processesEric Paris
commit 7d8b6c63751cfbbe5eef81a48c22978b3407a3ad upstream. This is effectively a revert of 7b9a7ec565505699f503b4fcf61500dceb36e744 plus fixing it a different way... We found, when trying to run an application from an application which had dropped privs that the kernel does security checks on undefined capability bits. This was ESPECIALLY difficult to debug as those undefined bits are hidden from /proc/$PID/status. Consider a root application which drops all capabilities from ALL 4 capability sets. We assume, since the application is going to set eff/perm/inh from an array that it will clear not only the defined caps less than CAP_LAST_CAP, but also the higher 28ish bits which are undefined future capabilities. The BSET gets cleared differently. Instead it is cleared one bit at a time. The problem here is that in security/commoncap.c::cap_task_prctl() we actually check the validity of a capability being read. So any task which attempts to 'read all things set in bset' followed by 'unset all things set in bset' will not even attempt to unset the undefined bits higher than CAP_LAST_CAP. So the 'parent' will look something like: CapInh: 0000000000000000 CapPrm: 0000000000000000 CapEff: 0000000000000000 CapBnd: ffffffc000000000 All of this 'should' be fine. Given that these are undefined bits that aren't supposed to have anything to do with permissions. But they do... So lets now consider a task which cleared the eff/perm/inh completely and cleared all of the valid caps in the bset (but not the invalid caps it couldn't read out of the kernel). We know that this is exactly what the libcap-ng library does and what the go capabilities library does. They both leave you in that above situation if you try to clear all of you capapabilities from all 4 sets. If that root task calls execve() the child task will pick up all caps not blocked by the bset. The bset however does not block bits higher than CAP_LAST_CAP. So now the child task has bits in eff which are not in the parent. These are 'meaningless' undefined bits, but still bits which the parent doesn't have. The problem is now in cred_cap_issubset() (or any operation which does a subset test) as the child, while a subset for valid cap bits, is not a subset for invalid cap bits! So now we set durring commit creds that the child is not dumpable. Given it is 'more priv' than its parent. It also means the parent cannot ptrace the child and other stupidity. The solution here: 1) stop hiding capability bits in status This makes debugging easier! 2) stop giving any task undefined capability bits. it's simple, it you don't put those invalid bits in CAP_FULL_SET you won't get them in init and you won't get them in any other task either. This fixes the cap_issubset() tests and resulting fallout (which made the init task in a docker container untraceable among other things) 3) mask out undefined bits when sys_capset() is called as it might use ~0, ~0 to denote 'all capabilities' for backward/forward compatibility. This lets 'capsh --caps="all=eip" -- -c /bin/bash' run. 4) mask out undefined bit when we read a file capability off of disk as again likely all bits are set in the xattr for forward/backward compatibility. This lets 'setcap all+pe /bin/bash; /bin/bash' run Signed-off-by: Eric Paris <eparis@redhat.com> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Andrew Vagin <avagin@openvz.org> Cc: Andrew G. Morgan <morgan@kernel.org> Cc: Serge E. Hallyn <serge.hallyn@canonical.com> Cc: Kees Cook <keescook@chromium.org> Cc: Steve Grubb <sgrubb@redhat.com> Cc: Dan Walsh <dwalsh@redhat.com> Signed-off-by: James Morris <james.l.morris@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-17reiserfs: Fix use after free in journal teardownJan Kara
commit 01777836c87081e4f68c4a43c9abe6114805f91e upstream. If do_journal_release() races with do_journal_end() which requeues delayed works for transaction flushing, we can leave work items for flushing outstanding transactions queued while freeing them. That results in use after free and possible crash in run_timers_softirq(). Fix the problem by not requeueing works if superblock is being shut down (MS_ACTIVE not set) and using cancel_delayed_work_sync() in do_journal_release(). Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-17reiserfs: fix corruption introduced by balance_leaf refactorJeff Mahoney
commit 27d0e5bc85f3341b9ba66f0c23627cf9d7538c9d upstream. Commits f1f007c308e (reiserfs: balance_leaf refactor, pull out balance_leaf_insert_left) and cf22df182bf (reiserfs: balance_leaf refactor, pull out balance_leaf_paste_left) missed that the `body' pointer was getting repositioned. Subsequent users of the pointer would expect it to be repositioned, and as a result, parts of the tree would get overwritten. The most common observed corruption is indirect block pointers being overwritten. Since the body value isn't actually used anymore in the called routines, we can pass back the offset it should be shifted. We constify the body and ih pointers in the balance_leaf as a mostly-free preventative measure. Reported-and-tested-by: Jeff Chua <jeff.chua.linux@gmail.com> Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-05NFSv4: Fix problems with close in the presence of a delegationTrond Myklebust
commit aee7af356e151494d5014f57b33460b162f181b5 upstream. In the presence of delegations, we can no longer assume that the state->n_rdwr, state->n_rdonly, state->n_wronly reflect the open stateid share mode, and so we need to calculate the initial value for calldata->arg.fmode using the state->flags. Reported-by: James Drews <drews@engr.wisc.edu> Fixes: 88069f77e1ac5 (NFSv41: Fix a potential state leakage when...) Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-05NFSv4: Don't clear the open state when we just did an OPEN_DOWNGRADETrond Myklebust
commit 412f6c4c26fb1eba8844290663837561ac53fa6e upstream. If we did an OPEN_DOWNGRADE, then the right thing to do on success, is to apply the new open mode to the struct nfs4_state. Instead, we were unconditionally clearing the state, making it appear to our state machinery as if we had just performed a CLOSE. Fixes: 226056c5c312b (NFSv4: Use correct locking when updating nfs4_state...) Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-05NFSv3: Fix another acl regressionTrond Myklebust
commit f87d928f6d98644d39809a013a22f981d39017cf upstream. When creating a new object on the NFS server, we should not be sending posix setacl requests unless the preceding posix_acl_create returned a non-trivial acl. Doing so, causes Solaris servers in particular to return an EINVAL. Fixes: 013cdf1088d72 (nfs: use generic posix ACL infrastructure,,,) Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1132786 Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-05svcrdma: Select NFSv4.1 backchannel transport based on forward channelChuck Lever
commit 3c45ddf823d679a820adddd53b52c6699c9a05ac upstream. The current code always selects XPRT_TRANSPORT_BC_TCP for the back channel, even when the forward channel was not TCP (eg, RDMA). When a 4.1 mount is attempted with RDMA, the server panics in the TCP BC code when trying to send CB_NULL. Instead, construct the transport protocol number from the forward channel transport or'd with XPRT_TRANSPORT_BC. Transports that do not support bi-directional RPC will not have registered a "BC" transport, causing create_backchannel_client() to fail immediately. Fixes: https://bugzilla.linux-nfs.org/show_bug.cgi?id=265 Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-05nfs: reject changes to resvport and sharecache during remountScott Mayhew
commit 71a6ec8ac587418ceb6b420def1ca44b334c1ff7 upstream. Commit c8e47028 made it possible to change resvport/noresvport and sharecache/nosharecache via a remount operation, neither of which should be allowed. Signed-off-by: Scott Mayhew <smayhew@redhat.com> Fixes: c8e47028 (nfs: Apply NFS_MOUNT_CMP_FLAGMASK to nfs_compare_remount_data) Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-05nfs3_list_one_acl(): check get_acl() result with IS_ERR_OR_NULLAndrey Utkin
commit 7a9e75a185e6b3a3860e6a26fb6e88691fc2c9d9 upstream. There was a check for result being not NULL. But get_acl() may return NULL, or ERR_PTR, or actual pointer. The purpose of the function where current change is done is to "list ACLs only when they are available", so any error condition of get_acl() mustn't be elevated, and returning 0 there is still valid. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=81111 Signed-off-by: Andrey Utkin <andrey.krieger.utkin@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Fixes: 74adf83f5d77 (nfs: only show Posix ACLs in listxattr if actually...) Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-05NFSD: Decrease nfsd_users in nfsd_startup_generic failKinglong Mee
commit d9499a95716db0d4bc9b67e88fd162133e7d6b08 upstream. A memory allocation failure could cause nfsd_startup_generic to fail, in which case nfsd_users wouldn't be incorrectly left elevated. After nfsd restarts nfsd_startup_generic will then succeed without doing anything--the first consequence is likely nfs4_start_net finding a bad laundry_wq and crashing. Signed-off-by: Kinglong Mee <kinglongmee@gmail.com> Fixes: 4539f14981ce "nfsd: replace boolean nfsd_up flag by users counter" Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-05jbd2: fix descriptor block size handling errors with journal_csumDarrick J. Wong
commit db9ee220361de03ee86388f9ea5e529eaad5323c upstream. It turns out that there are some serious problems with the on-disk format of journal checksum v2. The foremost is that the function to calculate descriptor tag size returns sizes that are too big. This causes alignment issues on some architectures and is compounded by the fact that some parts of jbd2 use the structure size (incorrectly) to determine the presence of a 64bit journal instead of checking the feature flags. Therefore, introduce journal checksum v3, which enlarges the descriptor block tag format to allow for full 32-bit checksums of journal blocks, fix the journal tag function to return the correct sizes, and fix the jbd2 recovery code to use feature flags to determine 64bitness. Add a few function helpers so we don't have to open-code quite so many pieces. Switching to a 16-byte block size was found to increase journal size overhead by a maximum of 0.1%, to convert a 32-bit journal with no checksumming to a 32-bit journal with checksum v3 enabled. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reported-by: TR Reardon <thomas_reardon@hotmail.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-05jbd2: fix infinite loop when recovering corrupt journal blocksDarrick J. Wong
commit 022eaa7517017efe4f6538750c2b59a804dc7df7 upstream. When recovering the journal, don't fall into an infinite loop if we encounter a corrupt journal block. Instead, just skip the block and return an error, which fails the mount and thus forces the user to run a full filesystem fsck. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-05ext4: fix same-dir rename when inline data directory overflowsDarrick J. Wong
commit d80d448c6c5bdd32605b78a60fe8081d82d4da0f upstream. When performing a same-directory rename, it's possible that adding or setting the new directory entry will cause the directory to overflow the inline data area, which causes the directory to be converted to an extent-based directory. Under this circumstance it is necessary to re-read the directory when deleting the old dirent because the "old directory" context still points to i_block in the inode table, which is now an extent tree root! The delete fails with an FS error, and the subsequent fsck complains about incorrect link counts and hardlinked directories. Test case (originally found with flat_dir_test in the metadata_csum test program): # mkfs.ext4 -O inline_data /dev/sda # mount /dev/sda /mnt # mkdir /mnt/x # touch /mnt/x/changelog.gz /mnt/x/copyright /mnt/x/README.Debian # sync # for i in /mnt/x/*; do mv $i $i.longer; done # ls -la /mnt/x/ total 0 -rw-r--r-- 1 root root 0 Aug 25 12:03 changelog.gz.longer -rw-r--r-- 1 root root 0 Aug 25 12:03 copyright -rw-r--r-- 1 root root 0 Aug 25 12:03 copyright.longer -rw-r--r-- 1 root root 0 Aug 25 12:03 README.Debian.longer (Hey! Why are there four files now??) Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-05ext4: update i_disksize coherently with block allocation on error pathDmitry Monakhov
commit 6603120e96eae9a5d6228681ae55c7fdc998d1bb upstream. In case of delalloc block i_disksize may be less than i_size. So we have to update i_disksize each time we allocated and submitted some blocks beyond i_disksize. We weren't doing this on the error paths, so fix this. testcase: xfstest generic/019 Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-05ext4: fix transaction issues for ext4_fallocate and ext_zero_rangeDmitry Monakhov
commit c174e6d6979a04b7b77b93f244396be4b81f8bfb upstream. After commit f282ac19d86f we use different transactions for preallocation and i_disksize update which result in complain from fsck after power-failure. spotted by generic/019. IMHO this is regression because fs becomes inconsistent, even more 'e2fsck -p' will no longer works (which drives admins go crazy) Same transaction requirement applies ctime,mtime updates testcase: xfstest generic/019 Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-05ext4: fix incorect journal credits reservation in ext4_zero_rangeDmitry Monakhov
commit 69dc9536405213c1d545fcace1fc15c481d00aae upstream. Currently we reserve only 4 blocks but in worst case scenario ext4_zero_partial_blocks() may want to zeroout and convert two non adjacent blocks. Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-05ext4: move i_size,i_disksize update routines to helper functionDmitry Monakhov
commit 4631dbf677ded0419fee35ca7408285dabfaef1a upstream. Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-05Btrfs: fix task hang under heavy compressed writeLiu Bo
commit 9e0af23764344f7f1b68e4eefbe7dc865018b63d upstream. This has been reported and discussed for a long time, and this hang occurs in both 3.15 and 3.16. Btrfs now migrates to use kernel workqueue, but it introduces this hang problem. Btrfs has a kind of work queued as an ordered way, which means that its ordered_func() must be processed in the way of FIFO, so it usually looks like -- normal_work_helper(arg) work = container_of(arg, struct btrfs_work, normal_work); work->func() <---- (we name it work X) for ordered_work in wq->ordered_list ordered_work->ordered_func() ordered_work->ordered_free() The hang is a rare case, first when we find free space, we get an uncached block group, then we go to read its free space cache inode for free space information, so it will file a readahead request btrfs_readpages() for page that is not in page cache __do_readpage() submit_extent_page() btrfs_submit_bio_hook() btrfs_bio_wq_end_io() submit_bio() end_workqueue_bio() <--(ret by the 1st endio) queue a work(named work Y) for the 2nd also the real endio() So the hang occurs when work Y's work_struct and work X's work_struct happens to share the same address. A bit more explanation, A,B,C -- struct btrfs_work arg -- struct work_struct kthread: worker_thread() pick up a work_struct from @worklist process_one_work(arg) worker->current_work = arg; <-- arg is A->normal_work worker->current_func(arg) normal_work_helper(arg) A = container_of(arg, struct btrfs_work, normal_work); A->func() A->ordered_func() A->ordered_free() <-- A gets freed B->ordered_func() submit_compressed_extents() find_free_extent() load_free_space_inode() ... <-- (the above readhead stack) end_workqueue_bio() btrfs_queue_work(work C) B->ordered_free() As if work A has a high priority in wq->ordered_list and there are more ordered works queued after it, such as B->ordered_func(), its memory could have been freed before normal_work_helper() returns, which means that kernel workqueue code worker_thread() still has worker->current_work pointer to be work A->normal_work's, ie. arg's address. Meanwhile, work C is allocated after work A is freed, work C->normal_work and work A->normal_work are likely to share the same address(I confirmed this with ftrace output, so I'm not just guessing, it's rare though). When another kthread picks up work C->normal_work to process, and finds our kthread is processing it(see find_worker_executing_work()), it'll think work C as a collision and skip then, which ends up nobody processing work C. So the situation is that our kthread is waiting forever on work C. Besides, there're other cases that can lead to deadlock, but the real problem is that all btrfs workqueue shares one work->func, -- normal_work_helper, so this makes each workqueue to have its own helper function, but only a wraper pf normal_work_helper. With this patch, I no long hit the above hang. Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-05Btrfs: fix filemap_flush call in btrfs_file_releaseChris Mason
commit f6dc45c7a93a011dff6eb9b2ffda59c390c7705a upstream. We should only be flushing on close if the file was flagged as needing it during truncate. I broke this with my ordered data vs transaction commit deadlock fix. Thanks to Miao Xie for catching this. Signed-off-by: Chris Mason <clm@fb.com> Reported-by: Miao Xie <miaox@cn.fujitsu.com> Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-05Btrfs: fix crash on endio of reading corrupted blockLiu Bo
commit 38c1c2e44bacb37efd68b90b3f70386a8ee370ee upstream. The crash is ------------[ cut here ]------------ kernel BUG at fs/btrfs/extent_io.c:2124! [...] Workqueue: btrfs-endio normal_work_helper [btrfs] RIP: 0010:[<ffffffffa02d6055>] [<ffffffffa02d6055>] end_bio_extent_readpage+0xb45/0xcd0 [btrfs] This is in fact a regression. It is because we forgot to increase @offset properly in reading corrupted block, so that the @offset remains, and this leads to checksum errors while reading left blocks queued up in the same bio, and then ends up with hiting the above BUG_ON. Reported-by: Chris Murphy <lists@colorremedies.com> Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-05btrfs: disable strict file flushes for renames and truncatesChris Mason
commit 8d875f95da43c6a8f18f77869f2ef26e9594fecc upstream. Truncates and renames are often used to replace old versions of a file with new versions. Applications often expect this to be an atomic replacement, even if they haven't done anything to make sure the new version is fully on disk. Btrfs has strict flushing in place to make sure that renaming over an old file with a new file will fully flush out the new file before allowing the transaction commit with the rename to complete. This ordering means the commit code needs to be able to lock file pages, and there are a few paths in the filesystem where we will try to end a transaction with the page lock held. It's rare, but these things can deadlock. This patch removes the ordered flushes and switches to a best effort filemap_flush like ext4 uses. It's not perfect, but it should fix the deadlocks. Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-05Btrfs: fix compressed write corruption on enospcLiu Bo
commit ce62003f690dff38d3164a632ec69efa15c32cbf upstream. When failing to allocate space for the whole compressed extent, we'll fallback to uncompressed IO, but we've forgotten to redirty the pages which belong to this compressed extent, and these 'clean' pages will simply skip 'submit' part and go to endio directly, at last we got data corruption as we write nothing. Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Tested-By: Martin Steigerwald <martin@lichtvoll.de> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-05Btrfs: read lock extent buffer while walking backrefsFilipe Manana
commit 6f7ff6d7832c6be13e8c95598884dbc40ad69fb7 upstream. Before processing the extent buffer, acquire a read lock on it, so that we're safe against concurrent updates on the extent buffer. Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-05Btrfs: fix csum tree corruption, duplicate and outdated checksumsFilipe Manana
commit 27b9a8122ff71a8cadfbffb9c4f0694300464f3b upstream. Under rare circumstances we can end up leaving 2 versions of a checksum for the same file extent range. The reason for this is that after calling btrfs_next_leaf we process slot 0 of the leaf it returns, instead of processing the slot set in path->slots[0]. Most of the time (by far) path->slots[0] is 0, but after btrfs_next_leaf() releases the path and before it searches for the next leaf, another task might cause a split of the next leaf, which migrates some of its keys to the leaf we were processing before calling btrfs_next_leaf(). In this case btrfs_next_leaf() returns again the same leaf but with path->slots[0] having a slot number corresponding to the first new key it got, that is, a slot number that didn't exist before calling btrfs_next_leaf(), as the leaf now has more keys than it had before. So we must really process the returned leaf starting at path->slots[0] always, as it isn't always 0, and the key at slot 0 can have an offset much lower than our search offset/bytenr. For example, consider the following scenario, where we have: sums->bytenr: 40157184, sums->len: 16384, sums end: 40173568 four 4kb file data blocks with offsets 40157184, 40161280, 40165376, 40169472 Leaf N: slot = 0 slot = btrfs_header_nritems() - 1 |-------------------------------------------------------------------| | [(CSUM CSUM 39239680), size 8] ... [(CSUM CSUM 40116224), size 4] | |-------------------------------------------------------------------| Leaf N + 1: slot = 0 slot = btrfs_header_nritems() - 1 |--------------------------------------------------------------------| | [(CSUM CSUM 40161280), size 32] ... [((CSUM CSUM 40615936), size 8 | |--------------------------------------------------------------------| Because we are at the last slot of leaf N, we call btrfs_next_leaf() to find the next highest key, which releases the current path and then searches for that next key. However after releasing the path and before finding that next key, the item at slot 0 of leaf N + 1 gets moved to leaf N, due to a call to ctree.c:push_leaf_left() (via ctree.c:split_leaf()), and therefore btrfs_next_leaf() will returns us a path again with leaf N but with the slot pointing to its new last key (CSUM CSUM 40161280). This new version of leaf N is then: slot = 0 slot = btrfs_header_nritems() - 2 slot = btrfs_header_nritems() - 1 |----------------------------------------------------------------------------------------------------| | [(CSUM CSUM 39239680), size 8] ... [(CSUM CSUM 40116224), size 4] [(CSUM CSUM 40161280), size 32] | |----------------------------------------------------------------------------------------------------| And incorrecly using slot 0, makes us set next_offset to 39239680 and we jump into the "insert:" label, which will set tmp to: tmp = min((sums->len - total_bytes) >> blocksize_bits, (next_offset - file_key.offset) >> blocksize_bits) = min((16384 - 0) >> 12, (39239680 - 40157184) >> 12) = min(4, (u64)-917504 = 18446744073708634112 >> 12) = 4 and ins_size = csum_size * tmp = 4 * 4 = 16 bytes. In other words, we insert a new csum item in the tree with key (CSUM_OBJECTID CSUM_KEY 40157184 = sums->bytenr) that contains the checksums for all the data (4 blocks of 4096 bytes each = sums->len). Which is wrong, because the item with key (CSUM CSUM 40161280) (the one that was moved from leaf N + 1 to the end of leaf N) contains the old checksums of the last 12288 bytes of our data and won't get those old checksums removed. So this leaves us 2 different checksums for 3 4kb blocks of data in the tree, and breaks the logical rule: Key_N+1.offset >= Key_N.offset + length_of_data_its_checksums_cover An obvious bad effect of this is that a subsequent csum tree lookup to get the checksum of any of the blocks with logical offset of 40161280, 40165376 or 40169472 (the last 3 4kb blocks of file data), will get the old checksums. Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-05Btrfs: Fix memory corruption by ulist_add_merge() on 32bit archTakashi Iwai
commit 4eb1f66dce6c4dc28dd90a7ffbe6b2b1cb08aa4e upstream. We've got bug reports that btrfs crashes when quota is enabled on 32bit kernel, typically with the Oops like below: BUG: unable to handle kernel NULL pointer dereference at 00000004 IP: [<f9234590>] find_parent_nodes+0x360/0x1380 [btrfs] *pde = 00000000 Oops: 0000 [#1] SMP CPU: 0 PID: 151 Comm: kworker/u8:2 Tainted: G S W 3.15.2-1.gd43d97e-default #1 Workqueue: btrfs-qgroup-rescan normal_work_helper [btrfs] task: f1478130 ti: f147c000 task.ti: f147c000 EIP: 0060:[<f9234590>] EFLAGS: 00010213 CPU: 0 EIP is at find_parent_nodes+0x360/0x1380 [btrfs] EAX: f147dda8 EBX: f147ddb0 ECX: 00000011 EDX: 00000000 ESI: 00000000 EDI: f147dda4 EBP: f147ddf8 ESP: f147dd38 DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 CR0: 8005003b CR2: 00000004 CR3: 00bf3000 CR4: 00000690 Stack: 00000000 00000000 f147dda4 00000050 00000001 00000000 00000001 00000050 00000001 00000000 d3059000 00000001 00000022 000000a8 00000000 00000000 00000000 000000a1 00000000 00000000 00000001 00000000 00000000 11800000 Call Trace: [<f923564d>] __btrfs_find_all_roots+0x9d/0xf0 [btrfs] [<f9237bb1>] btrfs_qgroup_rescan_worker+0x401/0x760 [btrfs] [<f9206148>] normal_work_helper+0xc8/0x270 [btrfs] [<c025e38b>] process_one_work+0x11b/0x390 [<c025eea1>] worker_thread+0x101/0x340 [<c026432b>] kthread+0x9b/0xb0 [<c0712a71>] ret_from_kernel_thread+0x21/0x30 [<c0264290>] kthread_create_on_node+0x110/0x110 This indicates a NULL corruption in prefs_delayed list. The further investigation and bisection pointed that the call of ulist_add_merge() results in the corruption. ulist_add_merge() takes u64 as aux and writes a 64bit value into old_aux. The callers of this function in backref.c, however, pass a pointer of a pointer to old_aux. That is, the function overwrites 64bit value on 32bit pointer. This caused a NULL in the adjacent variable, in this case, prefs_delayed. Here is a quick attempt to band-aid over this: a new function, ulist_add_merge_ptr() is introduced to pass/store properly a pointer value instead of u64. There are still ugly void ** cast remaining in the callers because void ** cannot be taken implicitly. But, it's safer than explicit cast to u64, anyway. Bugzilla: https://bugzilla.novell.com/show_bug.cgi?id=887046 Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-05ext4: fix BUG_ON in mb_free_blocks()Theodore Ts'o
commit c99d1e6e83b06744c75d9f5e491ed495a7086b7b upstream. If we suffer a block allocation failure (for example due to a memory allocation failure), it's possible that we will call ext4_discard_allocated_blocks() before we've actually allocated any blocks. In that case, fe_len and fe_start in ac->ac_f_ex will still be zero, and this will result in mb_free_blocks(inode, e4b, 0, 0) triggering the BUG_ON on mb_free_blocks(): BUG_ON(last >= (sb->s_blocksize << 3)); Fix this by bailing out of ext4_discard_allocated_blocks() if fs_len is zero. Also fix a missing ext4_mb_unload_buddy() call in ext4_discard_allocated_blocks(). Google-Bug-Id: 16844242 Fixes: 86f0afd463215fc3e58020493482faa4ac3a4d69 Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-05debugfs: Fix corrupted loop in debugfs_remove_recursiveSteven Rostedt
commit 485d44022a152c0254dd63445fdb81c4194cbf0e upstream. [ I'm currently running my tests on it now, and so far, after a few hours it has yet to blow up. I'll run it for 24 hours which it never succeeded in the past. ] The tracing code has a way to make directories within the debugfs file system as well as deleting them using mkdir/rmdir in the instance directory. This is very limited in functionality, such as there is no renames, and the parent directory "instance" can not be modified. The tracing code creates the instance directory from the debugfs code and then replaces the dentry->d_inode->i_op with its own to allow for mkdir/rmdir to work. When these are called, the d_entry and inode locks need to be released to call the instance creation and deletion code. That code has its own accounting and locking to serialize everything to prevent multiple users from causing harm. As the parent "instance" directory can not be modified this simplifies things. I created a stress test that creates several threads that randomly creates and deletes directories thousands of times a second. The code stood up to this test and I submitted it a while ago. Recently I added a new test that adds readers to the mix. While the instance directories were being added and deleted, readers would read from these directories and even enable tracing within them. This test was able to trigger a bug: general protection fault: 0000 [#1] PREEMPT SMP Modules linked in: ... CPU: 3 PID: 17789 Comm: rmdir Tainted: G W 3.15.0-rc2-test+ #41 Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./To be filled by O.E.M., BIOS SDBLI944.86P 05/08/2007 task: ffff88003786ca60 ti: ffff880077018000 task.ti: ffff880077018000 RIP: 0010:[<ffffffff811ed5eb>] [<ffffffff811ed5eb>] debugfs_remove_recursive+0x1bd/0x367 RSP: 0018:ffff880077019df8 EFLAGS: 00010246 RAX: 0000000000000002 RBX: ffff88006f0fe490 RCX: 0000000000000000 RDX: dead000000100058 RSI: 0000000000000246 RDI: ffff88003786d454 RBP: ffff88006f0fe640 R08: 0000000000000628 R09: 0000000000000000 R10: 0000000000000628 R11: ffff8800795110a0 R12: ffff88006f0fe640 R13: ffff88006f0fe640 R14: ffffffff81817d0b R15: ffffffff818188b7 FS: 00007ff13ae24700(0000) GS:ffff88007d580000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 0000003054ec7be0 CR3: 0000000076d51000 CR4: 00000000000007e0 Stack: ffff88007a41ebe0 dead000000100058 00000000fffffffe ffff88006f0fe640 0000000000000000 ffff88006f0fe678 ffff88007a41ebe0 ffff88003793a000 00000000fffffffe ffffffff810bde82 ffff88006f0fe640 ffff88007a41eb28 Call Trace: [<ffffffff810bde82>] ? instance_rmdir+0x15b/0x1de [<ffffffff81132e2d>] ? vfs_rmdir+0x80/0xd3 [<ffffffff81132f51>] ? do_rmdir+0xd1/0x139 [<ffffffff8124ad9e>] ? trace_hardirqs_on_thunk+0x3a/0x3c [<ffffffff814fea62>] ? system_call_fastpath+0x16/0x1b Code: fe ff ff 48 8d 75 30 48 89 df e8 c9 fd ff ff 85 c0 75 13 48 c7 c6 b8 cc d2 81 48 c7 c7 b0 cc d2 81 e8 8c 7a f5 ff 48 8b 54 24 08 <48> 8b 82 a8 00 00 00 48 89 d3 48 2d a8 00 00 00 48 89 44 24 08 RIP [<ffffffff811ed5eb>] debugfs_remove_recursive+0x1bd/0x367 RSP <ffff880077019df8> It took a while, but every time it triggered, it was always in the same place: list_for_each_entry_safe(child, next, &parent->d_subdirs, d_u.d_child) { Where the child->d_u.d_child seemed to be corrupted. I added lots of trace_printk()s to see what was wrong, and sure enough, it was always the child's d_u.d_child field. I looked around to see what touches it and noticed that in __dentry_kill() which calls dentry_free(): static void dentry_free(struct dentry *dentry) { /* if dentry was never visible to RCU, immediate free is OK */ if (!(dentry->d_flags & DCACHE_RCUACCESS)) __d_free(&dentry->d_u.d_rcu); else call_rcu(&dentry->d_u.d_rcu, __d_free); } I also noticed that __dentry_kill() unlinks the child->d_u.child under the parent->d_lock spin_lock. Looking back at the loop in debugfs_remove_recursive() it never takes the parent->d_lock to do the list walk. Adding more tracing, I was able to prove this was the issue: ftrace-t-15385 1.... 246662024us : dentry_kill <ffffffff81138b91>: free ffff88006d573600 rmdir-15409 2.... 246662024us : debugfs_remove_recursive <ffffffff811ec7e5>: child=ffff88006d573600 next=dead000000100058 The dentry_kill freed ffff88006d573600 just as the remove recursive was walking it. In order to fix this, the list walk needs to be modified a bit to take the parent->d_lock. The safe version is no longer necessary, as every time we remove a child, the parent->d_lock must be released and the list walk must start over. Each time a child is removed, even though it may still be on the list, it should be skipped by the first check in the loop: if (!debugfs_positive(child)) continue; Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-05ext4: fix ext4_discard_allocated_blocks() if we can't allocate the pa structTheodore Ts'o
commit 86f0afd463215fc3e58020493482faa4ac3a4d69 upstream. If there is a failure while allocating the preallocation structure, a number of blocks can end up getting marked in the in-memory buddy bitmap, and then not getting released. This can result in the following corruption getting reported by the kernel: EXT4-fs error (device sda3): ext4_mb_generate_buddy:758: group 1126, 12793 clusters in bitmap, 12729 in gd In that case, we need to release the blocks using mb_free_blocks(). Tested: fs smoke test; also demonstrated that with injected errors, the file system is no longer getting corrupted Google-Bug-Id: 16657874 Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-05ext4: fix punch hole on files with indirect mappingLukas Czerner
commit 4f579ae7de560e5f449587a6c3f02594d53d4d51 upstream. Currently punch hole code on files with direct/indirect mapping has some problems which may lead to a data loss. For example (from Jan Kara): fallocate -n -p 10240000 4096 will punch the range 10240000 - 12632064 instead of the range 1024000 - 10244096. Also the code is a bit weird and it's not using infrastructure provided by indirect.c, but rather creating it's own way. This patch fixes the issues as well as making the operation to run 4 times faster from my testing (punching out 60GB file). It uses similar approach used in ext4_ind_truncate() which takes advantage of ext4_free_branches() function. Also rename the ext4_free_hole_blocks() to something more sensible, like the equivalent we have for extent mapped files. Call it ext4_ind_remove_space(). This has been tested mostly with fsx and some xfstests which are testing punch hole but does not require unwritten extents which are not supported with direct/indirect mapping. Not problems showed up even with 1024k block size. Signed-off-by: Lukas Czerner <lczerner@redhat.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-05isofs: Fix unbounded recursion when processing relocated directoriesJan Kara
commit 410dd3cf4c9b36f27ed4542ee18b1af5e68645a4 upstream. We did not check relocated directory in any way when processing Rock Ridge 'CL' tag. Thus a corrupted isofs image can possibly have a CL entry pointing to another CL entry leading to possibly unbounded recursion in kernel code and thus stack overflow or deadlocks (if there is a loop created from CL entries). Fix the problem by not allowing CL entry to point to a directory entry with CL entry (such use makes no good sense anyway) and by checking whether CL entry doesn't point to itself. Reported-by: Chris Evans <cevans@google.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-08-01vfs: fix check for fallocate on active swapfileEric Biggers
Fix the broken check for calling sys_fallocate() on an active swapfile, introduced by commit 0790b31b69374ddadefe ("fs: disallow all fallocate operation on active swapfile"). Signed-off-by: Eric Biggers <ebiggers3@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-08-01direct-io: fix AIO regressionChristoph Hellwig
The direct-io.c rewrite to use the iov_iter infrastructure stopped updating the size field in struct dio_submit, and thus rendered the check for allowing asynchronous completions to always return false. Fix this by comparing it to the count of bytes in the iov_iter instead. Signed-off-by: Christoph Hellwig <hch@lst.de> Reported-by: Tim Chen <tim.c.chen@linux.intel.com> Tested-by: Tim Chen <tim.c.chen@linux.intel.com>
2014-07-29AFS: Correctly assemble the client UUIDDavid Howells
Correctly assemble the client UUID by OR'ing in the flags rather than assigning them over the other components. Reported-by: Himangi Saraogi <himangi774@gmail.com> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-07-27Merge branch 'vfs-for-3.16' of git://git.infradead.org/users/hch/vfsLinus Torvalds
Pull vfs fixes from Christoph Hellwig: "A vfsmount leak fix, and a compile warning fix" * 'vfs-for-3.16' of git://git.infradead.org/users/hch/vfs: fs: umount on symlink leaks mnt count direct-io: fix uninitialized warning in do_direct_IO()
2014-07-25Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse Pull fuse fixes from Miklos Szeredi: "These two pathes fix issues with the kernel-userspace protocol changes in v3.15" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: fuse: add FUSE_NO_OPEN_SUPPORT flag to INIT fuse: s_time_gran fix
2014-07-24fs: umount on symlink leaks mnt countVasily Averin
Currently umount on symlink blocks following umount: /vz is separate mount # ls /vz/ -al | grep test drwxr-xr-x. 2 root root 4096 Jul 19 01:14 testdir lrwxrwxrwx. 1 root root 11 Jul 19 01:16 testlink -> /vz/testdir # umount -l /vz/testlink umount: /vz/testlink: not mounted (expected) # lsof /vz # umount /vz umount: /vz: device is busy. (unexpected) In this case mountpoint_last() gets an extra refcount on path->mnt Signed-off-by: Vasily Averin <vvs@openvz.org> Acked-by: Ian Kent <raven@themaw.net> Acked-by: Jeff Layton <jlayton@primarydata.com> Cc: stable@vger.kernel.org Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-24direct-io: fix uninitialized warning in do_direct_IO()Boaz Harrosh
The following warnings: fs/direct-io.c: In function ‘__blockdev_direct_IO’: fs/direct-io.c:1011:12: warning: ‘to’ may be used uninitialized in this function [-Wmaybe-uninitialized] fs/direct-io.c:913:16: note: ‘to’ was declared here fs/direct-io.c:1011:12: warning: ‘from’ may be used uninitialized in this function [-Wmaybe-uninitialized] fs/direct-io.c:913:10: note: ‘from’ was declared here are false positive because dio_get_page() either fails, or sets both 'from' and 'to'. Paul Bolle said ... Maybe it's better to move initializing "to" and "from" out of dio_get_page(). That _might_ make it easier for both the the reader and the compiler to understand what's going on. Something like this: Christoph Hellwig said ... The fix of moving the code definitively looks nicer, while I think uninitialized_var is horrible wart that won't get anywhere near my code. Boaz Harrosh: I agree with Christoph and Paul Signed-off-by: Boaz Harrosh <boaz@plexistor.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-23Merge branch 'for-3.16' of git://linux-nfs.org/~bfields/linuxLinus Torvalds
Pull nfsd bugfix from Bruce Fields: "Another regression from the xdr encoding rewrite" * 'for-3.16' of git://linux-nfs.org/~bfields/linux: NFSD: Fix crash encoding lock reply on 32-bit
2014-07-23simple_xattr: permit 0-size extended attributesHugh Dickins
If a filesystem uses simple_xattr to support user extended attributes, LTP setxattr01 and xfstests generic/062 fail with "Cannot allocate memory": simple_xattr_alloc()'s wrap-around test mistakenly excludes values of zero size. Fix that off-by-one (but apparently no filesystem needs them yet). Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Jeff Layton <jlayton@poochiereds.net> Cc: Aristeu Rozanski <aris@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>