[PATCH][next] seg6: fix unintentional integer overflow on left shift

From: Colin King
Date: Mon Dec 07 2020 - 09:46:07 EST


From: Colin Ian King <colin.king@xxxxxxxxxxxxx>

Shifting the integer value 1 is evaluated using 32-bit arithmetic
and then used in an expression that expects a unsigned long value
leads to a potential integer overflow. Fix this by using the BIT
macro to perform the shift to avoid the overflow.

Addresses-Coverity: ("Uninitentional integer overflow")
Fixes: 964adce526a4 ("seg6: improve management of behavior attributes")
Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
---
net/ipv6/seg6_local.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/ipv6/seg6_local.c b/net/ipv6/seg6_local.c
index b07f7c1c82a4..d68de8cd1207 100644
--- a/net/ipv6/seg6_local.c
+++ b/net/ipv6/seg6_local.c
@@ -1366,7 +1366,7 @@ static void __destroy_attrs(unsigned long parsed_attrs, int max_parsed,
* attribute; otherwise, we call the destroy() callback.
*/
for (i = 0; i < max_parsed; ++i) {
- if (!(parsed_attrs & (1 << i)))
+ if (!(parsed_attrs & BIT(i)))
continue;

param = &seg6_action_params[i];
--
2.29.2