diff options
author | David Howells <dhowells@redhat.com> | 2015-06-18 16:32:31 +0300 |
---|---|---|
committer | Sasha Levin <sasha.levin@oracle.com> | 2015-10-28 05:14:24 +0300 |
commit | e93f29ffbb99d45f718c18832007d0c77091ed54 (patch) | |
tree | 77e0363036c6a5ded7224f3781d9ccb90b5e9768 /fs/dcache.c | |
parent | 9ebef9b7b9ea46b636c441989898aeef42bfe400 (diff) | |
download | linux-e93f29ffbb99d45f718c18832007d0c77091ed54.tar.xz |
overlayfs: Make f_path always point to the overlay and f_inode to the underlay
[ Upstream commit 4bacc9c9234c7c8eec44f5ed4e960d9f96fa0f01 ]
Make file->f_path always point to the overlay dentry so that the path in
/proc/pid/fd is correct and to ensure that label-based LSMs have access to the
overlay as well as the underlay (path-based LSMs probably don't need it).
Using my union testsuite to set things up, before the patch I see:
[root@andromeda union-testsuite]# bash 5</mnt/a/foo107
[root@andromeda union-testsuite]# ls -l /proc/$$/fd/
...
lr-x------. 1 root root 64 Jun 5 14:38 5 -> /a/foo107
[root@andromeda union-testsuite]# stat /mnt/a/foo107
...
Device: 23h/35d Inode: 13381 Links: 1
...
[root@andromeda union-testsuite]# stat -L /proc/$$/fd/5
...
Device: 23h/35d Inode: 13381 Links: 1
...
After the patch:
[root@andromeda union-testsuite]# bash 5</mnt/a/foo107
[root@andromeda union-testsuite]# ls -l /proc/$$/fd/
...
lr-x------. 1 root root 64 Jun 5 14:22 5 -> /mnt/a/foo107
[root@andromeda union-testsuite]# stat /mnt/a/foo107
...
Device: 23h/35d Inode: 40346 Links: 1
...
[root@andromeda union-testsuite]# stat -L /proc/$$/fd/5
...
Device: 23h/35d Inode: 40346 Links: 1
...
Note the change in where /proc/$$/fd/5 points to in the ls command. It was
pointing to /a/foo107 (which doesn't exist) and now points to /mnt/a/foo107
(which is correct).
The inode accessed, however, is the lower layer. The union layer is on device
25h/37d and the upper layer on 24h/36d.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Diffstat (limited to 'fs/dcache.c')
-rw-r--r-- | fs/dcache.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/fs/dcache.c b/fs/dcache.c index 28ee20aa121e..d25f8fdcd397 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -1528,7 +1528,8 @@ void d_set_d_op(struct dentry *dentry, const struct dentry_operations *op) DCACHE_OP_COMPARE | DCACHE_OP_REVALIDATE | DCACHE_OP_WEAK_REVALIDATE | - DCACHE_OP_DELETE )); + DCACHE_OP_DELETE | + DCACHE_OP_SELECT_INODE)); dentry->d_op = op; if (!op) return; @@ -1544,6 +1545,8 @@ void d_set_d_op(struct dentry *dentry, const struct dentry_operations *op) dentry->d_flags |= DCACHE_OP_DELETE; if (op->d_prune) dentry->d_flags |= DCACHE_OP_PRUNE; + if (op->d_select_inode) + dentry->d_flags |= DCACHE_OP_SELECT_INODE; } EXPORT_SYMBOL(d_set_d_op); |