4.9-stable review patch. If anyone has any objections, please let me know.
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From: Al Viro viro@zeniv.linux.org.uk
commit 5aa1437d2d9a068c0334bd7c9dafa8ec4f97f13b upstream.
open file, unlink it, then use ioctl(2) to make it immutable or append only. Now close it and watch the blocks *not* freed...
Immutable/append-only checks belong in ->setattr(). Note: the bug is old and backport to anything prior to 737f2e93b972 ("ext2: convert to use the new truncate convention") will need these checks lifted into ext2_setattr().
Cc: stable@kernel.org Signed-off-by: Al Viro viro@zeniv.linux.org.uk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- fs/ext2/inode.c | 10 ---------- 1 file changed, 10 deletions(-)
--- a/fs/ext2/inode.c +++ b/fs/ext2/inode.c @@ -1258,21 +1258,11 @@ do_indirects:
static void ext2_truncate_blocks(struct inode *inode, loff_t offset) { - /* - * XXX: it seems like a bug here that we don't allow - * IS_APPEND inode to have blocks-past-i_size trimmed off. - * review and fix this. - * - * Also would be nice to be able to handle IO errors and such, - * but that's probably too much to ask. - */ if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))) return; if (ext2_inode_is_fast_symlink(inode)) return; - if (IS_APPEND(inode) || IS_IMMUTABLE(inode)) - return;
dax_sem_down_write(EXT2_I(inode)); __ext2_truncate_blocks(inode, offset);