From: Changwei Ge chge@linux.alibaba.com
[ Upstream commit 783fda856e1034dee90a873f7654c418212d12d7 ]
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@linux.alibaba.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Reviewed-by: Joseph Qi joseph.qi@linux.alibaba.com Cc: Mark Fasheh mark@fasheh.com Cc: Joel Becker jlbec@evilplan.org Cc: Junxiao Bi junxiao.bi@oracle.com Cc: Changwei Ge gechangwei@live.cn Cc: Gang He ghe@suse.com Cc: Jun Piao piaojun@huawei.com Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20200407082754.17565-1-chge@linux.alibaba.com Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- fs/ocfs2/alloc.c | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/fs/ocfs2/alloc.c b/fs/ocfs2/alloc.c index a342f008e42f9..ff0e083ce2a1a 100644 --- a/fs/ocfs2/alloc.c +++ b/fs/ocfs2/alloc.c @@ -7403,6 +7403,10 @@ int ocfs2_truncate_inline(struct inode *inode, struct buffer_head *di_bh, 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);