[iproute,01/51] devlink: Check return code of strslashrsplit()

Submitted by Phil Sutter on Aug. 12, 2017, 12:04 p.m.

Details

Message ID 20170812120510.28750-2-phil@nwl.cc
State Changes Requested
Delegated to: stephen hemminger
Headers show

Commit Message

Phil Sutter Aug. 12, 2017, 12:04 p.m.
This function shouldn't fail because all callers of
__dl_argv_handle_port() make sure the passed string contains enough
slashes already, but better make sure if this changes in future the
function won't access uninitialized data.

Signed-off-by: Phil Sutter <phil@nwl.cc>
---
 devlink/devlink.c | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

Comments

stephen hemminger Aug. 15, 2017, 3:09 p.m.
On Sat, 12 Aug 2017 14:04:20 +0200
Phil Sutter <phil@nwl.cc> wrote:

> This function shouldn't fail because all callers of
> __dl_argv_handle_port() make sure the passed string contains enough
> slashes already, but better make sure if this changes in future the
> function won't access uninitialized data.
> 
> Signed-off-by: Phil Sutter <phil@nwl.cc>

Ok, but please don't go too far down the dead end of addressing all possible
"if code changes in the future this would be a bug". Keep to finding
and fixing the real bugs that exist today.

Patch hide | download patch | download mbox

diff --git a/devlink/devlink.c b/devlink/devlink.c
index f9bc16c350c40..de41a9f4aae10 100644
--- a/devlink/devlink.c
+++ b/devlink/devlink.c
@@ -526,18 +526,26 @@  static int __dl_argv_handle_port(char *str,
 				 char **p_bus_name, char **p_dev_name,
 				 uint32_t *p_port_index)
 {
-	char *handlestr = handlestr;
-	char *portstr = portstr;
+	char *handlestr;
+	char *portstr;
 	int err;
 
-	strslashrsplit(str, &handlestr, &portstr);
+	err = strslashrsplit(str, &handlestr, &portstr);
+	if (err) {
+		pr_err("Port identification \"%s\" is invalid\n", str);
+		return err;
+	}
 	err = strtouint32_t(portstr, p_port_index);
 	if (err) {
 		pr_err("Port index \"%s\" is not a number or not within range\n",
 		       portstr);
 		return err;
 	}
-	strslashrsplit(handlestr, p_bus_name, p_dev_name);
+	err = strslashrsplit(handlestr, p_bus_name, p_dev_name);
+	if (err) {
+		pr_err("Port identification \"%s\" is invalid\n", str);
+		return err;
+	}
 	return 0;
 }