[PATCH] lib: 842: Fix pointer dereferenced before checking

From: Haowen Bai
Date: Thu Mar 24 2022 - 22:33:20 EST


The pointer t is dereferencing comp_ops[c] before c is being
bound checked. Fix this by assigning comp_ops[c] to t only if
c is safy, otherwise just NULL.

Signed-off-by: Haowen Bai <baihaowen@xxxxxxxxx>
---
lib/842/842_compress.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/842/842_compress.c b/lib/842/842_compress.c
index c02baa4..6ff6973 100644
--- a/lib/842/842_compress.c
+++ b/lib/842/842_compress.c
@@ -222,7 +222,7 @@ static int add_bits(struct sw842_param *p, u64 d, u8 n)
static int add_template(struct sw842_param *p, u8 c)
{
int ret, i, b = 0;
- u8 *t = comp_ops[c];
+ u8 *t = c < OPS_MAX ? comp_ops[c] : NULL;
bool inv = false;

if (c >= OPS_MAX)
--
2.7.4