diff mbox series

[-next,v2] net/mlx5: Devcom, only use devcom after NULL check in mlx5_devcom_send_event()

Message ID 20230814072342.189470-1-lizetao1@huawei.com (mailing list archive)
State Awaiting Upstream
Delegated to: Netdev Maintainers
Headers show
Series [-next,v2] net/mlx5: Devcom, only use devcom after NULL check in mlx5_devcom_send_event() | expand

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Context Check Description
netdev/series_format warning Single patches do not need cover letters; 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: 1330 this patch: 1330
netdev/cc_maintainers success CCed 12 of 12 maintainers
netdev/build_clang success Errors and warnings before: 1353 this patch: 1353
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: 1353 this patch: 1353
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 16 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

lizetao Aug. 14, 2023, 7:23 a.m. UTC
There is a warning reported by kernel test robot:

smatch warnings:
drivers/net/ethernet/mellanox/mlx5/core/lib/devcom.c:264
	mlx5_devcom_send_event() warn: variable dereferenced before
		IS_ERR check devcom (see line 259)

The reason for the warning is that the pointer is used before check, put
the assignment to comp after devcom check to silence the warning.

Fixes: 88d162b47981 ("net/mlx5: Devcom, Infrastructure changes")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <error27@gmail.com>
Closes: https://lore.kernel.org/r/202308041028.AkXYDwJ6-lkp@intel.com/
Signed-off-by: Li Zetao <lizetao1@huawei.com>
---
v1 -> v2: Modify the order of variable declarations to end up with reverse x-mas tree order.
v1: https://lore.kernel.org/all/20230804092636.91357-1-lizetao1@huawei.com/

 drivers/net/ethernet/mellanox/mlx5/core/lib/devcom.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Comments

Leon Romanovsky Aug. 14, 2023, 10:11 a.m. UTC | #1
On Mon, Aug 14, 2023 at 03:23:42PM +0800, Li Zetao wrote:
> There is a warning reported by kernel test robot:
> 
> smatch warnings:
> drivers/net/ethernet/mellanox/mlx5/core/lib/devcom.c:264
> 	mlx5_devcom_send_event() warn: variable dereferenced before
> 		IS_ERR check devcom (see line 259)
> 
> The reason for the warning is that the pointer is used before check, put
> the assignment to comp after devcom check to silence the warning.
> 
> Fixes: 88d162b47981 ("net/mlx5: Devcom, Infrastructure changes")
> Reported-by: kernel test robot <lkp@intel.com>
> Reported-by: Dan Carpenter <error27@gmail.com>
> Closes: https://lore.kernel.org/r/202308041028.AkXYDwJ6-lkp@intel.com/
> Signed-off-by: Li Zetao <lizetao1@huawei.com>
> ---
> v1 -> v2: Modify the order of variable declarations to end up with reverse x-mas tree order.
> v1: https://lore.kernel.org/all/20230804092636.91357-1-lizetao1@huawei.com/
> 
>  drivers/net/ethernet/mellanox/mlx5/core/lib/devcom.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 

Thanks,
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
diff mbox series

Patch

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/lib/devcom.c b/drivers/net/ethernet/mellanox/mlx5/core/lib/devcom.c
index feb62d952643..00e67910e3ee 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/lib/devcom.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/lib/devcom.c
@@ -256,14 +256,15 @@  int mlx5_devcom_send_event(struct mlx5_devcom_comp_dev *devcom,
 			   int event, int rollback_event,
 			   void *event_data)
 {
-	struct mlx5_devcom_comp *comp = devcom->comp;
 	struct mlx5_devcom_comp_dev *pos;
+	struct mlx5_devcom_comp *comp;
 	int err = 0;
 	void *data;
 
 	if (IS_ERR_OR_NULL(devcom))
 		return -ENODEV;
 
+	comp = devcom->comp;
 	down_write(&comp->sem);
 	list_for_each_entry(pos, &comp->comp_dev_list_head, list) {
 		data = rcu_dereference_protected(pos->data, lockdep_is_held(&comp->sem));