From: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Date: Thu, 26 Jan 2012 17:13:19 +0000 (+0200)
Subject: lib/mpi: check for possible zero length
X-Git-Tag: firefly_0821_release~3680^2~3596^2~5
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=4877e056192245b387aae004ab38f7f3899dd57c;p=firefly-linux-kernel-4.4.55.git

lib/mpi: check for possible zero length

Buggy client might pass zero nlimbs which is meaningless.
Added check for zero length.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Reviewed-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
---

diff --git a/lib/mpi/mpiutil.c b/lib/mpi/mpiutil.c
index 6bfc41f62b8f..26e4ed31e256 100644
--- a/lib/mpi/mpiutil.c
+++ b/lib/mpi/mpiutil.c
@@ -58,6 +58,9 @@ mpi_ptr_t mpi_alloc_limb_space(unsigned nlimbs)
 {
 	size_t len = nlimbs * sizeof(mpi_limb_t);
 
+	if (!len)
+		return NULL;
+
 	return kmalloc(len, GFP_KERNEL);
 }