diff mbox series

[003/227] ntfs: add sanity check on allocation size

Message ID 20220322213840.3117DC340F4@smtp.kernel.org (mailing list archive)
State New
Headers show
Series [001/227] linux/kthread.h: remove unused macros | expand

Commit Message

Andrew Morton March 22, 2022, 9:38 p.m. UTC 
From: Dongliang Mu <mudongliangabcd@gmail.com>
Subject: ntfs: add sanity check on allocation size

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@hust.edu.cn
Reported-by: syzbot+3c765c5248797356edaa@syzkaller.appspotmail.com
Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>
Acked-by: Anton Altaparmakov <anton@tuxera.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 fs/ntfs/inode.c |    4 ++++
 1 file changed, 4 insertions(+)

Comments

Linus Torvalds March 22, 2022, 10:13 p.m. UTC | #1 
On Tue, Mar 22, 2022 at 2:38 PM Andrew Morton <akpm@linux-foundation.org> wrote:
>
> From: Dongliang Mu <mudongliangabcd@gmail.com>
> Subject: ntfs: add sanity check on allocation size
>
> ntfs_read_inode_mount invokes ntfs_malloc_nofs with zero allocation size.
> It triggers one BUG in the __ntfs_malloc function.

Hmm. A more serious issue seems to be that cast to (u32).

ntfs_attr_size(a) returns a 's64', so it just randomly truncates a
possibly bad value..

               Linus
diff mbox series

Patch

--- a/fs/ntfs/inode.c~ntfs-add-sanity-check-on-allocation-size
+++ a/fs/ntfs/inode.c
@@ -1881,6 +1881,10 @@  int ntfs_read_inode_mount(struct inode *
 		}
 		/* 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 "