diff options
| author | Darrick J. Wong <djwong@kernel.org> | 2022-03-08 21:50:43 +0300 |
|---|---|---|
| committer | Theodore Ts'o <tytso@mit.edu> | 2022-04-13 05:22:02 +0300 |
| commit | ad5cd4f4ee4d5fcdb1bfb7a0c073072961e70783 (patch) | |
| tree | 327d0219545bfb055b6af9985bdf9194361e2112 /fs/ext4/inode.c | |
| parent | 919adbfec29d5b89b3e45620653cbeeb0d42e6fd (diff) | |
| download | linux-ad5cd4f4ee4d5fcdb1bfb7a0c073072961e70783.tar.xz | |
ext4: fix fallocate to use file_modified to update permissions consistently
Since the initial introduction of (posix) fallocate back at the turn of
the century, it has been possible to use this syscall to change the
user-visible contents of files. This can happen by extending the file
size during a preallocation, or through any of the newer modes (punch,
zero, collapse, insert range). Because the call can be used to change
file contents, we should treat it like we do any other modification to a
file -- update the mtime, and drop set[ug]id privileges/capabilities.
The VFS function file_modified() does all this for us if pass it a
locked inode, so let's make fallocate drop permissions correctly.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20220308185043.GA117678@magnolia
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Diffstat (limited to 'fs/ext4/inode.c')
| -rw-r--r-- | fs/ext4/inode.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 26218088f63b..955dd978dccf 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -3946,8 +3946,9 @@ int ext4_break_layouts(struct inode *inode) * Returns: 0 on success or negative on failure */ -int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length) +int ext4_punch_hole(struct file *file, loff_t offset, loff_t length) { + struct inode *inode = file_inode(file); struct super_block *sb = inode->i_sb; ext4_lblk_t first_block, stop_block; struct address_space *mapping = inode->i_mapping; @@ -4009,6 +4010,10 @@ int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length) /* Wait all existing dio workers, newcomers will block on i_rwsem */ inode_dio_wait(inode); + ret = file_modified(file); + if (ret) + goto out_mutex; + /* * Prevent page faults from reinstantiating pages we have released from * page cache. |