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| author | Jeff Mahoney <jeffm@suse.de> | 2011-08-15 17:27:21 +0000 |
|---|---|---|
| committer | Chris Mason <chris.mason@oracle.com> | 2011-08-18 10:16:03 -0400 |
| commit | cb6db4e57632ba8589cc2f9fe1d0aa9116b87ab8 (patch) | |
| tree | 6cfeb1989e0ffdd9b536f908eb97269d0ddcbe65 /fs/btrfs | |
| parent | 93ee7a9340d64f20295aacc3fb6a22b759323280 (diff) | |
| download | linux-cb6db4e57632ba8589cc2f9fe1d0aa9116b87ab8.tar.bz2 | |
btrfs: btrfs_permission's RO check shouldn't apply to device nodes
This patch tightens the read-only access checks in btrfs_permission to
match the constraints in inode_permission. Currently, even though the
device node itself will be unmodified, read-write access to device nodes
is denied to when the device node resides on a read-only subvolume or a
is a file that has been marked read-only by the btrfs conversion utility.
With this patch applied, the check only affects regular files,
directories, and symlinks. It also restructures the code a bit so that
we don't duplicate the MAY_WRITE check for both tests.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Diffstat (limited to 'fs/btrfs')
| -rw-r--r-- | fs/btrfs/inode.c | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 15fceefbca0a..0ccc7438ad34 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -7354,11 +7354,15 @@ static int btrfs_set_page_dirty(struct page *page) static int btrfs_permission(struct inode *inode, int mask) { struct btrfs_root *root = BTRFS_I(inode)->root; + umode_t mode = inode->i_mode; - if (btrfs_root_readonly(root) && (mask & MAY_WRITE)) - return -EROFS; - if ((BTRFS_I(inode)->flags & BTRFS_INODE_READONLY) && (mask & MAY_WRITE)) - return -EACCES; + if (mask & MAY_WRITE && + (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode))) { + if (btrfs_root_readonly(root)) + return -EROFS; + if (BTRFS_I(inode)->flags & BTRFS_INODE_READONLY) + return -EACCES; + } return generic_permission(inode, mask); } |