summaryrefslogtreecommitdiffstats
path: root/fs/overlayfs/super.c
Commit message (Collapse)AuthorAgeFilesLines
* ovl: take mnt_want_write() for work/index dir setupAmir Goldstein2018-01-191-8/+17
| | | | | | | | | | | | | | | | | There are several write operations on upper fs not covered by mnt_want_write(): - test set/remove OPAQUE xattr - test create O_TMPFILE - set ORIGIN xattr in ovl_verify_origin() - cleanup of index entries in ovl_indexdir_cleanup() Some of these go way back, but this patch only applies over the v4.14 re-factoring of ovl_fill_super(). Cc: <stable@vger.kernel.org> #v4.14 Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: hash directory inodes for fsnotifyAmir Goldstein2018-01-191-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | fsnotify pins a watched directory inode in cache, but if directory dentry is released, new lookup will allocate a new dentry and a new inode. Directory events will be notified on the new inode, while fsnotify listener is watching the old pinned inode. Hash all directory inodes to reuse the pinned inode on lookup. Pure upper dirs are hashes by real upper inode, merge and lower dirs are hashed by real lower inode. The reference to lower inode was being held by the lower dentry object in the overlay dentry (oe->lowerstack[0]). Releasing the overlay dentry may drop lower inode refcount to zero. Add a refcount on behalf of the overlay inode to prevent that. As a by-product, hashing directory inodes also detects multiple redirected dirs to the same lower dir and uncovered redirected dir target on and returns -ESTALE on lookup. The reported issue dates back to initial version of overlayfs, but this patch depends on ovl_inode code that was introduced in kernel v4.13. Cc: <stable@vger.kernel.org> #v4.13 Reported-by: Niklas Cassel <niklas.cassel@axis.com> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Tested-by: Niklas Cassel <niklas.cassel@axis.com>
* ovl: Sync upper dirty data when syncing overlayfsChengguang Xu2017-12-111-4/+15
| | | | | | | | | | | | When executing filesystem sync or umount on overlayfs, dirty data does not get synced as expected on upper filesystem. This patch fixes sync filesystem method to keep data consistency for overlayfs. Signed-off-by: Chengguang Xu <cgxu@mykernel.net> Fixes: e593b2bf513d ("ovl: properly implement sync_filesystem()") Cc: <stable@vger.kernel.org> #4.11 Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: don't follow redirects if redirect_dir=offMiklos Szeredi2017-12-111-17/+51
| | | | | | | | | | | | | | | | | | Overlayfs is following redirects even when redirects are disabled. If this is unintentional (probably the majority of cases) then this can be a problem. E.g. upper layer comes from untrusted USB drive, and attacker crafts a redirect to enable read access to otherwise unreadable directories. If "redirect_dir=off", then turn off following as well as creation of redirects. If "redirect_dir=follow", then turn on following, but turn off creation of redirects (which is what "redirect_dir=off" does now). This is a backward incompatible change, so make it dependent on a config option. Reported-by: David Howells <dhowells@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* Rename superblock flags (MS_xyz -> SB_xyz)Linus Torvalds2017-11-271-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is a pure automated search-and-replace of the internal kernel superblock flags. The s_flags are now called SB_*, with the names and the values for the moment mirroring the MS_* flags that they're equivalent to. Note how the MS_xyz flags are the ones passed to the mount system call, while the SB_xyz flags are what we then use in sb->s_flags. The script to do this was: # places to look in; re security/*: it generally should *not* be # touched (that stuff parses mount(2) arguments directly), but # there are two places where we really deal with superblock flags. FILES="drivers/mtd drivers/staging/lustre fs ipc mm \ include/linux/fs.h include/uapi/linux/bfs_fs.h \ security/apparmor/apparmorfs.c security/apparmor/include/lib.h" # the list of MS_... constants SYMS="RDONLY NOSUID NODEV NOEXEC SYNCHRONOUS REMOUNT MANDLOCK \ DIRSYNC NOATIME NODIRATIME BIND MOVE REC VERBOSE SILENT \ POSIXACL UNBINDABLE PRIVATE SLAVE SHARED RELATIME KERNMOUNT \ I_VERSION STRICTATIME LAZYTIME SUBMOUNT NOREMOTELOCK NOSEC BORN \ ACTIVE NOUSER" SED_PROG= for i in $SYMS; do SED_PROG="$SED_PROG -e s/MS_$i/SB_$i/g"; done # we want files that contain at least one of MS_..., # with fs/namespace.c and fs/pnode.c excluded. L=$(for i in $SYMS; do git grep -w -l MS_$i $FILES; done| sort|uniq|grep -v '^fs/namespace.c'|grep -v '^fs/pnode.c') for f in $L; do sed -i $f $SED_PROG; done Requested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ovl: remove unneeded arg from ovl_verify_origin()Amir Goldstein2017-11-101-5/+3
| | | | | Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: rename ufs to ofsMiklos Szeredi2017-11-101-114/+114
| | | | | | | Rename all "struct ovl_fs" pointers to "ofs". The "ufs" name is historical and can only be found in overlayfs/super.c. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: clean up getting lower layersMiklos Szeredi2017-11-101-52/+48
| | | | | | | | Move calling ovl_get_lower_layers() into ovl_get_lowerstack(). ovl_get_lowerstack() now returns the root dentry's filled in ovl_entry. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: clean up workdir creationMiklos Szeredi2017-11-101-16/+15
| | | | | | | | | | | Move calling ovl_get_workdir() into ovl_get_workpath(). Rename ovl_get_workdir() to ovl_make_workdir() and ovl_get_workpath() to ovl_get_workdir(). Workpath is now not needed outside ovl_get_workdir(). Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: clean up getting upper layerMiklos Szeredi2017-11-101-22/+13
| | | | | | | | | Merge ovl_get_upper() and ovl_get_upperpath(). The resulting function is named ovl_get_upper(), though it still returns upperpath as well. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: move ovl_get_workdir() and ovl_get_lower_layers()Miklos Szeredi2017-11-101-101/+101
| | | | Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: reduce the number of arguments for ovl_workdir_create()Miklos Szeredi2017-11-101-16/+15
| | | | | | | Remove "sb" and "dentry" arguments of ovl_workdir_create() and related functions. Move setting MS_RDONLY flag to callers. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: change order of setup in ovl_fill_super()Miklos Szeredi2017-11-101-16/+14
| | | | | | | | | | Move ovl_get_upper() immediately after ovl_get_upperpath(), ovl_get_workdir() immediately after ovl_get_workdir() and ovl_get_lower_layers() immediately after ovl_get_lowerstack(). Also move prepare_creds() up to where other allocations are happening. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: factor out ovl_free_fs() helperMiklos Szeredi2017-11-101-45/+27
| | | | | | | This can be called both from ovl_put_super() and in the error cleanup path from ovl_fill_super(). Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: grab reference to workbasedir earlyMiklos Szeredi2017-11-091-7/+8
| | | | | | and related cleanups. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: split out ovl_get_indexdir() from ovl_fill_super()Miklos Szeredi2017-11-091-29/+40
| | | | | | | It's okay to get rid of the intermediate error label due to ufs being zeroed on allocation. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: split out ovl_get_lower_layers() from ovl_fill_super()Miklos Szeredi2017-11-091-38/+52
| | | | Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: split out ovl_get_workdir() from ovl_fill_super()Miklos Szeredi2017-11-091-51/+60
| | | | Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: split out ovl_get_upper() from ovl_fill_super()Miklos Szeredi2017-11-091-8/+19
| | | | | | And don't clobber ufs->upper_mnt on error. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: split out ovl_get_lowerstack() from ovl_fill_super()Miklos Szeredi2017-11-091-50/+72
| | | | Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: split out ovl_get_workpath() from ovl_fill_super()Miklos Szeredi2017-11-091-24/+37
| | | | | | | It's okay to get rid of the intermediate error label due to ufs being zeroed on allocation. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: split out ovl_get_upperpath() from ovl_fill_super()Miklos Szeredi2017-11-091-24/+35
| | | | | | | It's okay to get rid of the intermediate error label due to ufs being zeroed on allocation. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: use path_put_init() in error paths for ovl_fill_super()Miklos Szeredi2017-11-091-3/+3
| | | | | | This allows simplifying the error cleanup later. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: allocate anonymous devs for lowerdirsChandan Rajendra2017-11-091-2/+16
| | | | | | | | | | | | | | | Generate unique values of st_dev per lower layer for non-samefs overlay mount. The unique values are obtained by allocating anonymous bdevs for each of the lowerdirs in the overlayfs instance. The anonymous bdev is going to be returned by stat(2) for lowerdir non-dir entries in non-samefs case. [amir: split from ovl_getattr() and re-structure patches] Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: re-structure overlay lower layers in-memoryChandan Rajendra2017-11-091-28/+34
| | | | | | | | | | | | | | | | | | | | | | | Define new structures to represent overlay instance lower layers and overlay merge dir lower layers to make room for storing more per layer information in-memory. Instead of keeping the fs instance lower layers in an array of struct vfsmount, keep them in an array of new struct ovl_layer, that has a pointer to struct vfsmount. Instead of keeping the dentry lower layers in an array of struct path, keep them in an array of new struct ovl_path, that has a pointer to struct dentry and to struct ovl_layer. Add a small helper to find the fs layer id that correspopnds to a lower struct ovl_path and use it in ovl_lookup(). [amir: split re-structure from anonymous bdev patch] Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: move include of ovl_entry.h into overlayfs.hAmir Goldstein2017-11-091-1/+0
| | | | | | | | | | | | | Most overlayfs c files already explicitly include ovl_entry.h to use overlay entry struct definitions and upcoming changes are going to require even more c files to include this header. All overlayfs c files include overlayfs.h and overlayfs.h itself refers to some structs defined in ovl_entry.h, so it seems more logic to include ovl_entry.h from overlayfs.h than from c files. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: no direct iteration for dir with origin xattrAmir Goldstein2017-11-091-0/+2
| | | | | | | | | | | | | | | | If a non-merge dir in an overlay mount has an overlay.origin xattr, it means it was once an upper merge dir, which may contain whiteouts and then the lower dir was removed under it. Do not iterate real dir directly in this case to avoid exposing whiteouts. [SzM] Set OVL_WHITEOUT for all merge directories as well. [amir] A directory that was just copied up does not have the OVL_WHITEOUTS flag. We need to set it to fix merge dir iteration. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: add NULL check in ovl_alloc_inodeHirofumi Nakagawa2017-10-191-0/+3
| | | | | | | | This was detected by fault injection test Signed-off-by: Hirofumi Nakagawa <nklabs@gmail.com> Fixes: 13cf199d0088 ("ovl: allocate an ovl_inode struct") Cc: <stable@vger.kernel.org> # v4.13
* ovl: fix regression caused by exclusive upper/work dir protectionAmir Goldstein2017-10-051-8/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Enforcing exclusive ownership on upper/work dirs caused a docker regression: https://github.com/moby/moby/issues/34672. Euan spotted the regression and pointed to the offending commit. Vivek has brought the regression to my attention and provided this reproducer: Terminal 1: mount -t overlay -o workdir=work,lowerdir=lower,upperdir=upper none merged/ Terminal 2: unshare -m Terminal 1: umount merged mount -t overlay -o workdir=work,lowerdir=lower,upperdir=upper none merged/ mount: /root/overlay-testing/merged: none already mounted or mount point busy To fix the regression, I replaced the error with an alarming warning. With index feature enabled, mount does fail, but logs a suggestion to override exclusive dir protection by disabling index. Note that index=off mount does take the inuse locks, so a concurrent index=off will issue the warning and a concurrent index=on mount will fail. Documentation was updated to reflect this change. Fixes: 2cac0c00a6cd ("ovl: get exclusive ownership on upper/work dirs") Cc: <stable@vger.kernel.org> # v4.13 Reported-by: Euan Kemp <euank@euank.com> Reported-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* Merge branch 'work.mount' of ↵Linus Torvalds2017-09-141-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull mount flag updates from Al Viro: "Another chunk of fmount preparations from dhowells; only trivial conflicts for that part. It separates MS_... bits (very grotty mount(2) ABI) from the struct super_block ->s_flags (kernel-internal, only a small subset of MS_... stuff). This does *not* convert the filesystems to new constants; only the infrastructure is done here. The next step in that series is where the conflicts would be; that's the conversion of filesystems. It's purely mechanical and it's better done after the merge, so if you could run something like list=$(for i in MS_RDONLY MS_NOSUID MS_NODEV MS_NOEXEC MS_SYNCHRONOUS MS_MANDLOCK MS_DIRSYNC MS_NOATIME MS_NODIRATIME MS_SILENT MS_POSIXACL MS_KERNMOUNT MS_I_VERSION MS_LAZYTIME; do git grep -l $i fs drivers/staging/lustre drivers/mtd ipc mm include/linux; done|sort|uniq|grep -v '^fs/namespace.c$') sed -i -e 's/\<MS_RDONLY\>/SB_RDONLY/g' \ -e 's/\<MS_NOSUID\>/SB_NOSUID/g' \ -e 's/\<MS_NODEV\>/SB_NODEV/g' \ -e 's/\<MS_NOEXEC\>/SB_NOEXEC/g' \ -e 's/\<MS_SYNCHRONOUS\>/SB_SYNCHRONOUS/g' \ -e 's/\<MS_MANDLOCK\>/SB_MANDLOCK/g' \ -e 's/\<MS_DIRSYNC\>/SB_DIRSYNC/g' \ -e 's/\<MS_NOATIME\>/SB_NOATIME/g' \ -e 's/\<MS_NODIRATIME\>/SB_NODIRATIME/g' \ -e 's/\<MS_SILENT\>/SB_SILENT/g' \ -e 's/\<MS_POSIXACL\>/SB_POSIXACL/g' \ -e 's/\<MS_KERNMOUNT\>/SB_KERNMOUNT/g' \ -e 's/\<MS_I_VERSION\>/SB_I_VERSION/g' \ -e 's/\<MS_LAZYTIME\>/SB_LAZYTIME/g' \ $list and commit it with something along the lines of 'convert filesystems away from use of MS_... constants' as commit message, it would save a quite a bit of headache next cycle" * 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: VFS: Differentiate mount flags (MS_*) from internal superblock flags VFS: Convert sb->s_flags & MS_RDONLY to sb_rdonly(sb) vfs: Add sb_rdonly(sb) to query the MS_RDONLY flag on s_flags
| * VFS: Convert sb->s_flags & MS_RDONLY to sb_rdonly(sb)David Howells2017-07-171-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Firstly by applying the following with coccinelle's spatch: @@ expression SB; @@ -SB->s_flags & MS_RDONLY +sb_rdonly(SB) to effect the conversion to sb_rdonly(sb), then by applying: @@ expression A, SB; @@ ( -(!sb_rdonly(SB)) && A +!sb_rdonly(SB) && A | -A != (sb_rdonly(SB)) +A != sb_rdonly(SB) | -A == (sb_rdonly(SB)) +A == sb_rdonly(SB) | -!(sb_rdonly(SB)) +!sb_rdonly(SB) | -A && (sb_rdonly(SB)) +A && sb_rdonly(SB) | -A || (sb_rdonly(SB)) +A || sb_rdonly(SB) | -(sb_rdonly(SB)) != A +sb_rdonly(SB) != A | -(sb_rdonly(SB)) == A +sb_rdonly(SB) == A | -(sb_rdonly(SB)) && A +sb_rdonly(SB) && A | -(sb_rdonly(SB)) || A +sb_rdonly(SB) || A ) @@ expression A, B, SB; @@ ( -(sb_rdonly(SB)) ? 1 : 0 +sb_rdonly(SB) | -(sb_rdonly(SB)) ? A : B +sb_rdonly(SB) ? A : B ) to remove left over excess bracketage and finally by applying: @@ expression A, SB; @@ ( -(A & MS_RDONLY) != sb_rdonly(SB) +(bool)(A & MS_RDONLY) != sb_rdonly(SB) | -(A & MS_RDONLY) == sb_rdonly(SB) +(bool)(A & MS_RDONLY) == sb_rdonly(SB) ) to make comparisons against the result of sb_rdonly() (which is a bool) work correctly. Signed-off-by: David Howells <dhowells@redhat.com>
* | ovl: fix relatime for directoriesMiklos Szeredi2017-09-051-0/+3
| | | | | | | | | | | | | | | | | | | | Need to treat non-regular overlayfs files the same as regular files when checking for an atime update. Add a d_real() flag to make it return the upper dentry for all file types. Reported-by: "zhangyi (F)" <yi.zhang@huawei.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* | vfs: add flags to d_real()Miklos Szeredi2017-09-041-2/+2
| | | | | | | | | | | | | | Add a separate flags argument (in addition to the open flags) to control the behavior of d_real(). Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* | ovl: cleanup d_real for negativeMiklos Szeredi2017-09-041-3/+0
| | | | | | | | | | | | | | | | d_real() is never called with a negative dentry. So remove the d_is_negative() check (which would never trigger anyway, since d_is_reg() returns false for a negative dentry). Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* | ovl: constant d_ino for non-merge dirsMiklos Szeredi2017-07-271-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impure directories are ones which contain objects with origins (i.e. those that have been copied up). These are relevant to readdir operation only because of the d_ino field, no other transformation is necessary. Also a directory can become impure between two getdents(2) calls. This patch creates a cache for impure directories. Unlike the cache for merged directories, this one only contains entries with origin and is not refcounted but has a its lifetime tied to that of the dentry. Similarly to the merged cache, the impure cache is invalidated based on a version number. This version number is incremented when an entry with origin is added or removed from the directory. If the cache is empty, then the impure xattr is removed from the directory. This patch also fixes up handling of d_ino for the ".." entry if the parent directory is merged. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* | ovl: fix xattr get and set with selinuxMiklos Szeredi2017-07-201-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | inode_doinit_with_dentry() in SELinux wants to read the upper inode's xattr to get security label, and ovl_xattr_get() calls ovl_dentry_real(), which depends on dentry->d_inode, but d_inode is null and not initialized yet at this point resulting in an Oops. Fix by getting the upperdentry info from the inode directly in this case. Reported-by: Eryu Guan <eguan@redhat.com> Fixes: 09d8b586731b ("ovl: move __upperdentry to ovl_inode") Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* | ovl: remove unneeded check for IS_ERR()Amir Goldstein2017-07-131-4/+0
| | | | | | | | | | | | | | | | ovl_workdir_create() returns a valid index dentry or NULL. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* | ovl: fix random return value on mountAmir Goldstein2017-07-131-0/+1
|/ | | | | | | | | | | | | On failure to prepare_creds(), mount fails with a random return value, as err was last set to an integer cast of a valid lower mnt pointer or set to 0 if inodes index feature is enabled. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Fixes: 3fe6e52f0626 ("ovl: override creds with the ones from ...") Cc: <stable@vger.kernel.org> # v4.7 Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: cleanup orphan index entriesAmir Goldstein2017-07-041-1/+1
| | | | | | | | | | | | | | | | | index entry should live only as long as there are upper or lower hardlinks. Cleanup orphan index entries on mount and when dropping the last overlay inode nlink. When about to cleanup or link up to orphan index and the index inode nlink > 1, admit that something went wrong and adjust overlay nlink to index inode nlink - 1 to prevent it from dropping below zero. This could happen when adding lower hardlinks underneath a mounted overlay and then trying to unlink them. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: add flag for upper in ovl_entryMiklos Szeredi2017-07-041-0/+1
| | | | | | | | For rename, we need to ensure that an upper alias exists for hard links before attempting the operation. Introduce a flag in ovl_entry to track the state of the upper alias. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: cleanup bad and stale index entries on mountAmir Goldstein2017-07-041-0/+6
| | | | | | | | | | | | | | | | | | | Bad index entries are entries whose name does not match the origin file handle stored in trusted.overlay.origin xattr. Bad index entries could be a result of a system power off in the middle of copy up. Stale index entries are entries whose origin file handle is stale. Stale index entries could be a result of copying layers or removing lower entries while the overlay is not mounted. The case of copying layers should be detected earlier by the verification of upper root dir origin and index dir origin. Both bad and stale index entries are detected and removed on mount. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: verify index dir matches upper dirAmir Goldstein2017-07-041-2/+11
| | | | | | | | | | | | | | | | | | An index dir contains persistent hardlinks to files in upper dir. Therefore, we must never mount an existing index dir with a differnt upper dir. Store the upper root dir file handle in index dir inode when index dir is created and verify the file handle before using an existing index dir on mount. Add an 'is_upper' flag to the overlay file handle encoding and set it when encoding the upper root file handle. This is not critical for index dir verification, but it is good practice towards a standard overlayfs file handle format for NFS export. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: verify upper root dir matches lower root dirAmir Goldstein2017-07-041-0/+8
| | | | | | | | | | | When inodes index feature is enabled, verify that the file handle stored in upper root dir matches the lower root dir or fail to mount. If upper root dir has no stored file handle, encode and store the lower root dir file handle in overlay.origin xattr. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: introduce the inodes index dir featureAmir Goldstein2017-07-041-2/+64
| | | | | | | | | | | | | | | Create the index dir on mount. The index dir will contain hardlinks to upper inodes, named after the hex representation of their origin lower inodes. The index dir is going to be used to prevent breaking lower hardlinks on copy up and to implement overlayfs NFS export. Because the feature is not fully backward compat, enabling the feature is opt-in by config/module/mount option. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: generalize ovl_create_workdir()Amir Goldstein2017-07-041-16/+25
| | | | | | | | | | | | | | Pass in the subdir name to create and specify if subdir is persistent or if it should be cleaned up on every mount. Move fallback to readonly mount on failure to create dir and print of error message into the helper. This function is going to be used for creating the persistent 'index' dir under workbasedir. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: get exclusive ownership on upper/work dirsAmir Goldstein2017-07-041-3/+26
| | | | | | | | | | | | | | | Bad things can happen if several concurrent overlay mounts try to use the same upperdir/workdir path. Try to get the 'inuse' advisory lock on upperdir and workdir. Fail mount if another overlay mount instance or another user holds the 'inuse' lock on these directories. Note that this provides no protection for concurrent overlay mount that use overlapping (i.e. descendant) upper/work dirs. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: move cache and version to ovl_inodeMiklos Szeredi2017-07-041-0/+2
| | | | Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: use ovl_inode mutex to synchronize concurrent copy upAmir Goldstein2017-07-041-1/+2
| | | | | | | | | | | | Use the new ovl_inode mutex to synchonize concurrent copy up instead of the super block copy up workqueue. Moving the synchronization object from the overlay dentry to the overlay inode is needed for synchonizing concurrent copy up of lower hardlinks to the same upper inode. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: move impure to ovl_inodeMiklos Szeredi2017-07-041-1/+3
| | | | Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: move redirect to ovl_inodeMiklos Szeredi2017-07-041-1/+2
| | | | Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
OpenPOWER on IntegriCloud