UBIFS: Fix potential integer overflow in allocation
commit 353748a359f1821ee934afc579cf04572406b420 upstream.
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: 1e51764a3c2ac ("UBIFS: add new flash file system")
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/fs/ubifs/journal.c b/fs/ubifs/journal.c
index 04c4ec6..8ae1cd8 100644
--- a/fs/ubifs/journal.c
+++ b/fs/ubifs/journal.c
@@ -1283,10 +1283,11 @@ 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;