[patch net-next] devlink: append split port number to the port name

From: Jiri Pirko <redacted>

Instead of doing sprintf twice in case the port is split or not, append
the split port suffix in case the port is split.

Signed-off-by: Jiri Pirko <redacted>
---
 net/core/devlink.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/net/core/devlink.c b/net/core/devlink.c
index 06b2b1941dce..c7754c293010 100644
--- a/net/core/devlink.c
+++ b/net/core/devlink.c

@@ -8632,12 +8632,10 @@ static int __devlink_port_phys_port_name_get(struct devlink_port *devlink_port,
 	switch (attrs->flavour) {
 	case DEVLINK_PORT_FLAVOUR_PHYSICAL:
 	case DEVLINK_PORT_FLAVOUR_VIRTUAL:
-		if (!attrs->split)
-			n = snprintf(name, len, "p%u", attrs->phys.port_number);
-		else
-			n = snprintf(name, len, "p%us%u",
-				     attrs->phys.port_number,
-				     attrs->phys.split_subport_number);
+		n = snprintf(name, len, "p%u", attrs->phys.port_number);
+		if (attrs->split)
+			n += snprintf(name + n, len - n, "s%u",
+				      attrs->phys.split_subport_number);
 		break;
 	case DEVLINK_PORT_FLAVOUR_CPU:
 	case DEVLINK_PORT_FLAVOUR_DSA:

-- 
2.31.1

On Wed, 26 May 2021 12:35:08 +0200 Jiri Pirko wrote:

From: Jiri Pirko <redacted>

Instead of doing sprintf twice in case the port is split or not, append
the split port suffix in case the port is split.

Signed-off-by: Jiri Pirko <redacted>

snprintf() can return n > len, you need to check for this before
passing len - n as an unsigned argument below.

+		if (attrs->split)
+			n += snprintf(name + n, len - n, "s%u",
+				      attrs->phys.split_subport_number);
 		break;
 	case DEVLINK_PORT_FLAVOUR_CPU:
 	case DEVLINK_PORT_FLAVOUR_DSA:

Thu, May 27, 2021 at 02:05:56AM CEST, kuba@kernel.org wrote:

On Wed, 26 May 2021 12:35:08 +0200 Jiri Pirko wrote:

quoted

From: Jiri Pirko <redacted>

Instead of doing sprintf twice in case the port is split or not, append
the split port suffix in case the port is split.

Signed-off-by: Jiri Pirko <redacted>

quoted

diff --git a/net/core/devlink.c b/net/core/devlink.c
index 06b2b1941dce..c7754c293010 100644
--- a/net/core/devlink.c
+++ b/net/core/devlink.c

@@ -8632,12 +8632,10 @@ static int __devlink_port_phys_port_name_get(struct devlink_port *devlink_port,
 	switch (attrs->flavour) {
 	case DEVLINK_PORT_FLAVOUR_PHYSICAL:
 	case DEVLINK_PORT_FLAVOUR_VIRTUAL:
-		if (!attrs->split)
-			n = snprintf(name, len, "p%u", attrs->phys.port_number);
-		else
-			n = snprintf(name, len, "p%us%u",
-				     attrs->phys.port_number,
-				     attrs->phys.split_subport_number);
+		n = snprintf(name, len, "p%u", attrs->phys.port_number);

snprintf() can return n > len, you need to check for this before
passing len - n as an unsigned argument below.

Correct, will send v2. Thanks!

quoted

+		if (attrs->split)
+			n += snprintf(name + n, len - n, "s%u",
+				      attrs->phys.split_subport_number);
 		break;
 	case DEVLINK_PORT_FLAVOUR_CPU:
 	case DEVLINK_PORT_FLAVOUR_DSA: