diff mbox series

[2/3,v2] sfc: fix uninitialized variable use

Message ID 20230619091215.2731541-2-arnd@kernel.org (mailing list archive)
State Accepted
Commit f61d2d5cf142436cd1a02ddc78425e91116b8b0d
Delegated to: Netdev Maintainers
Headers show
Series [1/3,v2] sfc: add CONFIG_INET dependency for TC offload | expand

Checks

Context Check Description
netdev/series_format warning Series does not have a cover letter; Target tree name not specified in the subject
netdev/tree_selection success Guessed tree name to be net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 8 this patch: 8
netdev/cc_maintainers success CCed 10 of 10 maintainers
netdev/build_clang success Errors and warnings before: 8 this patch: 8
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 8 this patch: 8
netdev/checkpatch warning WARNING: Please use correct Fixes: style 'Fixes: <12 chars of sha1> ("<title line>")' - ie: 'Fixes: 7e5e7d800011 ("sfc: neighbour lookup for TC encap action offload")'
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Arnd Bergmann June 19, 2023, 9:12 a.m. UTC 
From: Arnd Bergmann <arnd@arndb.de>

The new efx_bind_neigh() function contains a broken code path when IPV6 is
disabled:

drivers/net/ethernet/sfc/tc_encap_actions.c:144:7: error: variable 'n' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
                if (encap->type & EFX_ENCAP_FLAG_IPV6) {
                    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/net/ethernet/sfc/tc_encap_actions.c:184:8: note: uninitialized use occurs here
                if (!n) {
                     ^
drivers/net/ethernet/sfc/tc_encap_actions.c:144:3: note: remove the 'if' if its condition is always false
                if (encap->type & EFX_ENCAP_FLAG_IPV6) {
                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/net/ethernet/sfc/tc_encap_actions.c:141:22: note: initialize the variable 'n' to silence this warning
                struct neighbour *n;
                                   ^
                                    = NULL

Change it to use the existing error handling path here.

Fixes: 7e5e7d800011a ("sfc: neighbour lookup for TC encap action offload")
Suggested-by: Edward Cree <ecree.xilinx@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
v2: use 'goto' instead of incorrectly entering another error path
---
 drivers/net/ethernet/sfc/tc_encap_actions.c | 1 +
 1 file changed, 1 insertion(+)

Comments

Edward Cree June 19, 2023, 10:06 a.m. UTC | #1 
On 19/06/2023 10:12, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@arndb.de>
> 
> The new efx_bind_neigh() function contains a broken code path when IPV6 is
> disabled:
> 
> drivers/net/ethernet/sfc/tc_encap_actions.c:144:7: error: variable 'n' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
>                 if (encap->type & EFX_ENCAP_FLAG_IPV6) {
>                     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/net/ethernet/sfc/tc_encap_actions.c:184:8: note: uninitialized use occurs here
>                 if (!n) {
>                      ^
> drivers/net/ethernet/sfc/tc_encap_actions.c:144:3: note: remove the 'if' if its condition is always false
>                 if (encap->type & EFX_ENCAP_FLAG_IPV6) {
>                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/net/ethernet/sfc/tc_encap_actions.c:141:22: note: initialize the variable 'n' to silence this warning
>                 struct neighbour *n;
>                                    ^
>                                     = NULL
> 
> Change it to use the existing error handling path here.
> 
> Fixes: 7e5e7d800011a ("sfc: neighbour lookup for TC encap action offload")
> Suggested-by: Edward Cree <ecree.xilinx@gmail.com>
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Reviewed-by: Edward Cree <ecree.xilinx@gmail.com>

> ---
> v2: use 'goto' instead of incorrectly entering another error path
> ---
>  drivers/net/ethernet/sfc/tc_encap_actions.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/net/ethernet/sfc/tc_encap_actions.c b/drivers/net/ethernet/sfc/tc_encap_actions.c
> index aac259528e73e..7e8bcdb222ad1 100644
> --- a/drivers/net/ethernet/sfc/tc_encap_actions.c
> +++ b/drivers/net/ethernet/sfc/tc_encap_actions.c
> @@ -164,6 +164,7 @@ static int efx_bind_neigh(struct efx_nic *efx,
>  			 */
>  			rc = -EOPNOTSUPP;
>  			NL_SET_ERR_MSG_MOD(extack, "No IPv6 support (neigh bind)");
> +			goto out_free;
>  #endif
>  		} else {
>  			rt = ip_route_output_key(net, &flow4);
>
diff mbox series

Patch

diff --git a/drivers/net/ethernet/sfc/tc_encap_actions.c b/drivers/net/ethernet/sfc/tc_encap_actions.c
index aac259528e73e..7e8bcdb222ad1 100644
--- a/drivers/net/ethernet/sfc/tc_encap_actions.c
+++ b/drivers/net/ethernet/sfc/tc_encap_actions.c
@@ -164,6 +164,7 @@  static int efx_bind_neigh(struct efx_nic *efx,
 			 */
 			rc = -EOPNOTSUPP;
 			NL_SET_ERR_MSG_MOD(extack, "No IPv6 support (neigh bind)");
+			goto out_free;
 #endif
 		} else {
 			rt = ip_route_output_key(net, &flow4);