mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-29 22:02:02 +00:00
btrfs: fix fallocate to use file_modified to update permissions consistently
[ Upstream commit 05fd9564e9
]
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 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.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
parent
6dded62e5a
commit
bb93369f93
1 changed files with 11 additions and 2 deletions
|
@ -2878,8 +2878,9 @@ int btrfs_replace_file_extents(struct btrfs_inode *inode,
|
|||
return ret;
|
||||
}
|
||||
|
||||
static int btrfs_punch_hole(struct inode *inode, loff_t offset, loff_t len)
|
||||
static int btrfs_punch_hole(struct file *file, loff_t offset, loff_t len)
|
||||
{
|
||||
struct inode *inode = file_inode(file);
|
||||
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
|
||||
struct btrfs_root *root = BTRFS_I(inode)->root;
|
||||
struct extent_state *cached_state = NULL;
|
||||
|
@ -2911,6 +2912,10 @@ static int btrfs_punch_hole(struct inode *inode, loff_t offset, loff_t len)
|
|||
goto out_only_mutex;
|
||||
}
|
||||
|
||||
ret = file_modified(file);
|
||||
if (ret)
|
||||
goto out_only_mutex;
|
||||
|
||||
lockstart = round_up(offset, btrfs_inode_sectorsize(BTRFS_I(inode)));
|
||||
lockend = round_down(offset + len,
|
||||
btrfs_inode_sectorsize(BTRFS_I(inode))) - 1;
|
||||
|
@ -3351,7 +3356,7 @@ static long btrfs_fallocate(struct file *file, int mode,
|
|||
return -EOPNOTSUPP;
|
||||
|
||||
if (mode & FALLOC_FL_PUNCH_HOLE)
|
||||
return btrfs_punch_hole(inode, offset, len);
|
||||
return btrfs_punch_hole(file, offset, len);
|
||||
|
||||
/*
|
||||
* Only trigger disk allocation, don't trigger qgroup reserve
|
||||
|
@ -3373,6 +3378,10 @@ static long btrfs_fallocate(struct file *file, int mode,
|
|||
goto out;
|
||||
}
|
||||
|
||||
ret = file_modified(file);
|
||||
if (ret)
|
||||
goto out;
|
||||
|
||||
/*
|
||||
* TODO: Move these two operations after we have checked
|
||||
* accurate reserved space, or fallocate can still fail but
|
||||
|
|
Loading…
Reference in a new issue