Re: [Linux-NTFS-Dev] [PATCH] ntfs: add sanity check on allocation size

[Anton A. <an...@tu...>]

Hi Andrew,

Please could you merge this?  Thanks a lot in advance!

Dongliang, that looks good, thanks!

Best regards,

Anton

On 20 Jan 2022, at 09:49, Dongliang Mu <dz...@hu...<mailto:dz...@hu...>> wrote:

From: Dongliang Mu <mud...@gm...<mailto:mud...@gm...>>

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.

Reported-by: syz...@sy...<mailto:syz...@sy...>
Signed-off-by: Dongliang Mu <mud...@gm...<mailto:mud...@gm...>>
Acked-by: Anton Altaparmakov <an...@tu...<mailto:an...@tu...>>
---
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 "
--
2.25.1


--
Anton Altaparmakov <anton at tuxera.com<http://tuxera.com>> (replace at with @)
Lead in File System Development, Tuxera Inc., http://www.tuxera.com/
Linux NTFS maintainer