In order to be sure that 'buff' is never truncated, its size should be
12, not 11.
When building with W=1, this fixes the following warnings:
drivers/infiniband/hw/mlx4/sysfs.c: In function ‘add_port_entries’:
drivers/infiniband/hw/mlx4/sysfs.c:268:34: error: ‘sprintf’ may write a terminating nul past the end of the destination [-Werror=format-overflow=]
268 | sprintf(buff, "%d", i);
| ^
drivers/infiniband/hw/mlx4/sysfs.c:268:17: note: ‘sprintf’ output between 2 and 12 bytes into a destination of size 11
268 | sprintf(buff, "%d", i);
| ^~~~~~~~~~~~~~~~~~~~~~
drivers/infiniband/hw/mlx4/sysfs.c:286:34: error: ‘sprintf’ may write a terminating nul past the end of the destination [-Werror=format-overflow=]
286 | sprintf(buff, "%d", i);
| ^
drivers/infiniband/hw/mlx4/sysfs.c:286:17: note: ‘sprintf’ output between 2 and 12 bytes into a destination of size 11
286 | sprintf(buff, "%d", i);
| ^~~~~~~~~~~~~~~~~~~~~~
Fixes: c1e7e466120b ("IB/mlx4: Add iov directory in sysfs under the ib device")
Signed-off-by: Christophe JAILLET <[email protected]>
---
We could also use snprintf(), but it would just lead to a bigger patch for
no additional benefit.
This patch is already certainly more a clean-up than a fix.
---
drivers/infiniband/hw/mlx4/sysfs.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/infiniband/hw/mlx4/sysfs.c b/drivers/infiniband/hw/mlx4/sysfs.c
index 24ee79aa2122..88f534cf690e 100644
--- a/drivers/infiniband/hw/mlx4/sysfs.c
+++ b/drivers/infiniband/hw/mlx4/sysfs.c
@@ -223,7 +223,7 @@ void del_sysfs_port_mcg_attr(struct mlx4_ib_dev *device, int port_num,
static int add_port_entries(struct mlx4_ib_dev *device, int port_num)
{
int i;
- char buff[11];
+ char buff[12];
struct mlx4_ib_iov_port *port = NULL;
int ret = 0 ;
struct ib_port_attr attr;
--
2.34.1
On Sat, 23 Sep 2023 07:55:56 +0200, Christophe JAILLET wrote:
> In order to be sure that 'buff' is never truncated, its size should be
> 12, not 11.
>
> When building with W=1, this fixes the following warnings:
>
> drivers/infiniband/hw/mlx4/sysfs.c: In function ‘add_port_entries’:
> drivers/infiniband/hw/mlx4/sysfs.c:268:34: error: ‘sprintf’ may write a terminating nul past the end of the destination [-Werror=format-overflow=]
> 268 | sprintf(buff, "%d", i);
> | ^
> drivers/infiniband/hw/mlx4/sysfs.c:268:17: note: ‘sprintf’ output between 2 and 12 bytes into a destination of size 11
> 268 | sprintf(buff, "%d", i);
> | ^~~~~~~~~~~~~~~~~~~~~~
> drivers/infiniband/hw/mlx4/sysfs.c:286:34: error: ‘sprintf’ may write a terminating nul past the end of the destination [-Werror=format-overflow=]
> 286 | sprintf(buff, "%d", i);
> | ^
> drivers/infiniband/hw/mlx4/sysfs.c:286:17: note: ‘sprintf’ output between 2 and 12 bytes into a destination of size 11
> 286 | sprintf(buff, "%d", i);
> | ^~~~~~~~~~~~~~~~~~~~~~
>
> [...]
Applied, thanks!
[1/1] IB/mlx4: Fix the size of a buffer in add_port_entries()
https://git.kernel.org/rdma/rdma/c/d7f393430a17c2
Best regards,
--
Leon Romanovsky <[email protected]>