UBIFS: Fix potential integer overflow in allocation

There is potential for the size and len fields in ubifs_data_node to be
too large causing either a negative value for the length fields or an
integer overflow leading to an incorrect memory allocation. Likewise,
when the len field is small, an integer underflow may occur.

Signed-off-by: Silvio Cesare <silvio.cesare@gmail.com>
Fixes: 1e51764a3c ("UBIFS: add new flash file system")
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
This commit is contained in:
Silvio Cesare 2018-05-04 13:44:02 +10:00 committed by Kees Cook
parent f3278e3f0a
commit 353748a359

View File

@ -1282,10 +1282,11 @@ static int truncate_data_node(const struct ubifs_info *c, const struct inode *in
int *new_len)
{
void *buf;
int err, dlen, compr_type, out_len, old_dlen;
int err, compr_type;
u32 dlen, out_len, old_dlen;
out_len = le32_to_cpu(dn->size);
buf = kmalloc(out_len * WORST_COMPR_FACTOR, GFP_NOFS);
buf = kmalloc_array(out_len, WORST_COMPR_FACTOR, GFP_NOFS);
if (!buf)
return -ENOMEM;