sysctl: fix null checking in bin_dn_node_address()
The null check of `strchr() + 1' is broken, which is always non-null,
leading to OOB read. Instead, check the result of strchr().
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/kernel/sysctl_binary.c b/kernel/sysctl_binary.c
index b25115e..ebf7235 100644
--- a/kernel/sysctl_binary.c
+++ b/kernel/sysctl_binary.c
@@ -1171,9 +1171,10 @@
/* Convert the decnet address to binary */
result = -EIO;
- nodep = strchr(buf, '.') + 1;
+ nodep = strchr(buf, '.');
if (!nodep)
goto out;
+ ++nodep;
area = simple_strtoul(buf, NULL, 10);
node = simple_strtoul(nodep, NULL, 10);