From 353748a359f1821ee934afc579cf04572406b420 Mon Sep 17 00:00:00 2001 From: Silvio Cesare Date: Fri, 4 May 2018 13:44:02 +1000 Subject: [PATCH] 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 Fixes: 1e51764a3c2ac ("UBIFS: add new flash file system") Cc: stable@vger.kernel.org Signed-off-by: Kees Cook --- fs/ubifs/journal.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/fs/ubifs/journal.c b/fs/ubifs/journal.c index da8afdfccaa6..07b4956e0425 100644 --- a/fs/ubifs/journal.c +++ b/fs/ubifs/journal.c @@ -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;