[PATCH 5.16 0802/1017] ntfs: add sanity check on allocation size

From: Greg Kroah-Hartman
Date: Tue Apr 05 2022 - 09:42:31 EST


From: Dongliang Mu <mudongliangabcd@xxxxxxxxx>

[ Upstream commit 714fbf2647b1a33d914edd695d4da92029c7e7c0 ]

ntfs_read_inode_mount invokes ntfs_malloc_nofs with zero allocation
size. It triggers one BUG in the __ntfs_malloc function.

Fix this by adding sanity check on ni->attr_list_size.

Link: https://lkml.kernel.org/r/20220120094914.47736-1-dzm91@xxxxxxxxxxx
Reported-by: syzbot+3c765c5248797356edaa@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Dongliang Mu <mudongliangabcd@xxxxxxxxx>
Acked-by: Anton Altaparmakov <anton@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/ntfs/inode.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/fs/ntfs/inode.c b/fs/ntfs/inode.c
index 4474adb393ca..517b71c73aa9 100644
--- a/fs/ntfs/inode.c
+++ b/fs/ntfs/inode.c
@@ -1881,6 +1881,10 @@ int ntfs_read_inode_mount(struct inode *vi)
}
/* Now allocate memory for the attribute list. */
ni->attr_list_size = (u32)ntfs_attr_size(a);
+ if (!ni->attr_list_size) {
+ ntfs_error(sb, "Attr_list_size is zero");
+ goto put_err_out;
+ }
ni->attr_list = ntfs_malloc_nofs(ni->attr_list_size);
if (!ni->attr_list) {
ntfs_error(sb, "Not enough memory to allocate buffer "
--
2.34.1