[PATCH] f2fs: return -EPERM given generic mask

From: Jaegeuk Kim
Date: Thu May 06 2021 - 15:13:56 EST


In f2fs_fileattr_set(),

if (!fa->flags_valid)
mask &= FS_COMMON_FL;

In this case, we should not allow to set FS_COMPR_FL, instead of BUG_ON.

/* Flags shared betwen flags/xflags */
(FS_SYNC_FL | FS_IMMUTABLE_FL | FS_APPEND_FL | \
FS_NODUMP_FL | FS_NOATIME_FL | FS_DAX_FL | \
FS_PROJINHERIT_FL)

Fixes: 4c5b47997521 ("vfs: add fileattr ops")
Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
---
fs/f2fs/file.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index e01ce802cf10..38015ef84893 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -1817,7 +1817,9 @@ static int f2fs_setflags_common(struct inode *inode, u32 iflags, u32 mask)
struct f2fs_inode_info *fi = F2FS_I(inode);
u32 masked_flags = fi->i_flags & mask;

- f2fs_bug_on(F2FS_I_SB(inode), (iflags & ~mask));
+ /* mask can be shrunk by flags_valid selector */
+ if (iflags & ~mask)
+ return -EPERM;

/* Is it quota file? Do not allow user to mess with it */
if (IS_NOQUOTA(inode))
--
2.31.1.607.g51e8a6a459-goog