[PATCH] can: raw: raw_getsockopt(): reduce scope of err

From: Marc Kleine-Budde
Date: Tue Feb 20 2024 - 03:16:35 EST


Reduce the scope of the variable "err" to the individual cases. This
is to avoid the mistake of setting "err" in the mistaken belief that
it will be evaluated later.

Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
---
net/can/raw.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/net/can/raw.c b/net/can/raw.c
index 897ffc17d850..2bb3eab98af0 100644
--- a/net/can/raw.c
+++ b/net/can/raw.c
@@ -756,7 +756,6 @@ static int raw_getsockopt(struct socket *sock, int level, int optname,
struct raw_sock *ro = raw_sk(sk);
int len;
void *val;
- int err = 0;

if (level != SOL_CAN_RAW)
return -EINVAL;
@@ -766,7 +765,9 @@ static int raw_getsockopt(struct socket *sock, int level, int optname,
return -EINVAL;

switch (optname) {
- case CAN_RAW_FILTER:
+ case CAN_RAW_FILTER: {
+ int err = 0;
+
lock_sock(sk);
if (ro->count > 0) {
int fsize = ro->count * sizeof(struct can_filter);
@@ -791,7 +792,7 @@ static int raw_getsockopt(struct socket *sock, int level, int optname,
if (!err)
err = put_user(len, optlen);
return err;
-
+ }
case CAN_RAW_ERR_FILTER:
if (len > sizeof(can_err_mask_t))
len = sizeof(can_err_mask_t);
@@ -822,7 +823,9 @@ static int raw_getsockopt(struct socket *sock, int level, int optname,
val = &ro->xl_frames;
break;

- case CAN_RAW_XL_VCID_OPTS:
+ case CAN_RAW_XL_VCID_OPTS: {
+ int err = 0;
+
/* user space buffer to small for VCID opts? */
if (len < sizeof(ro->raw_vcid_opts)) {
/* return -ERANGE and needed space in optlen */
@@ -839,6 +842,7 @@ static int raw_getsockopt(struct socket *sock, int level, int optname,
err = put_user(len, optlen);
return err;

+ }
case CAN_RAW_JOIN_FILTERS:
if (len > sizeof(int))
len = sizeof(int);

---
base-commit: c8fba5d6df5e476aa791db4f1f014dad2bb5e904
change-id: 20240220-raw-setsockopt-f6e173cdbbbb

Best regards,
--
Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>