From: Erez Zadok <ezk@xxxxxxxxxxxxx>
Bug fix to test if a lower branch is readonly, even when given negative
dentries.
Signed-off-by: Erez Zadok <ezk@xxxxxxxxxxxxx>
Signed-off-by: Josef 'Jeff' Sipek <jsipek@xxxxxxxxxxxxx>
---
fs/unionfs/union.h | 19 ++++++++++++++-----
1 files changed, 14 insertions(+), 5 deletions(-)
diff --git a/fs/unionfs/union.h b/fs/unionfs/union.h
index 33c2137..26d886e 100644
--- a/fs/unionfs/union.h
+++ b/fs/unionfs/union.h
@@ -396,14 +396,23 @@ static inline int is_robranch_super(const struct super_block *sb, int index)
/* Is this file on a read-only branch? */
static inline int is_robranch_idx(const struct dentry *dentry, int index)
{
- int err = 0;
+ struct super_block *lower_sb;
BUG_ON(index < 0);
- if ((!(branchperms(dentry->d_sb, index) & MAY_WRITE)) ||
- IS_RDONLY(unionfs_lower_dentry_idx(dentry, index)->d_inode))
- err = -EROFS;
- return err;
+ if (!(branchperms(dentry->d_sb, index) & MAY_WRITE))
+ return -EROFS;
+
+ lower_sb = unionfs_lower_super_idx(dentry->d_sb, index);
+ BUG_ON(lower_sb == NULL);
+ /*
+ * test sb flags directly, not IS_RDONLY(lower_inode) because the
+ * lower_dentry could be a negative.
+ */
+ if (lower_sb->s_flags & MS_RDONLY)
+ return -EROFS;
+
+ return 0;
}
static inline int is_robranch(const struct dentry *dentry)
--
1.5.2.2.238.g7cbf2f2
-
To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
