From: Changwei Ge <chge@xxxxxxxxxxxxxxxxx> commit 783fda856e1034dee90a873f7654c418212d12d7 upstream. Linux fallocate(2) with FALLOC_FL_PUNCH_HOLE mode set, its offset can exceed the inode size. Ocfs2 now doesn't allow that offset beyond inode size. This restriction is not necessary and violates fallocate(2) semantics. If fallocate(2) offset is beyond inode size, just return success and do nothing further. Otherwise, ocfs2 will crash the kernel. kernel BUG at fs/ocfs2//alloc.c:7264! ocfs2_truncate_inline+0x20f/0x360 [ocfs2] ocfs2_remove_inode_range+0x23c/0xcb0 [ocfs2] __ocfs2_change_file_space+0x4a5/0x650 [ocfs2] ocfs2_fallocate+0x83/0xa0 [ocfs2] vfs_fallocate+0x148/0x230 SyS_fallocate+0x48/0x80 do_syscall_64+0x79/0x170 Signed-off-by: Changwei Ge <chge@xxxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Reviewed-by: Joseph Qi <joseph.qi@xxxxxxxxxxxxxxxxx> Cc: Mark Fasheh <mark@xxxxxxxxxx> Cc: Joel Becker <jlbec@xxxxxxxxxxxx> Cc: Junxiao Bi <junxiao.bi@xxxxxxxxxx> Cc: Changwei Ge <gechangwei@xxxxxxx> Cc: Gang He <ghe@xxxxxxxx> Cc: Jun Piao <piaojun@xxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Link: http://lkml.kernel.org/r/20200407082754.17565-1-chge@xxxxxxxxxxxxxxxxx Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/ocfs2/alloc.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/fs/ocfs2/alloc.c +++ b/fs/ocfs2/alloc.c @@ -7403,6 +7403,10 @@ int ocfs2_truncate_inline(struct inode * struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data; struct ocfs2_inline_data *idata = &di->id2.i_data; + /* No need to punch hole beyond i_size. */ + if (start >= i_size_read(inode)) + return 0; + if (end > i_size_read(inode)) end = i_size_read(inode);
