3.16.51-rc1 review patch. If anyone has any objections, please let me know.
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From: Arnd Bergmann arnd@arndb.de
commit d0dbf771309fecd73f4ac1566c1400cb12807ee2 upstream.
gcc-7 points out that a negative port_num value would overflow the string buffer:
drivers/infiniband/hw/mlx4/sysfs.c: In function 'mlx4_ib_device_register_sysfs': drivers/infiniband/hw/mlx4/sysfs.c:251:16: error: 'sprintf' may write a terminating nul past the end of the destination [-Werror=format-overflow=] drivers/infiniband/hw/mlx4/sysfs.c:251:2: note: 'sprintf' output between 2 and 11 bytes into a destination of size 10 drivers/infiniband/hw/mlx4/sysfs.c:303:17: error: 'sprintf' may write a terminating nul past the end of the destination [-Werror=format-overflow=] drivers/infiniband/hw/mlx4/sysfs.c:303:3: note: 'sprintf' output between 2 and 11 bytes into a destination of size 10
While we should be able to assume that port_num is positive here, making the buffer one byte longer has no downsides and avoids the warning.
Fixes: c1e7e466120b ("IB/mlx4: Add iov directory in sysfs under the ib device") Link: http://lkml.kernel.org/r/20170714120720.906842-23-arnd@arndb.de Signed-off-by: Arnd Bergmann arnd@arndb.de Reviewed-by: Leon Romanovsky leonro@mellanox.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Ben Hutchings ben@decadent.org.uk --- drivers/infiniband/hw/mlx4/sysfs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/infiniband/hw/mlx4/sysfs.c +++ b/drivers/infiniband/hw/mlx4/sysfs.c @@ -241,7 +241,7 @@ void del_sysfs_port_mcg_attr(struct mlx4 static int add_port_entries(struct mlx4_ib_dev *device, int port_num) { int i; - char buff[10]; + char buff[11]; struct mlx4_ib_iov_port *port = NULL; int ret = 0 ; struct ib_port_attr attr;