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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?F4ec0BDNpVafmTXdKfPqow1Onodc0ePDn+nhxIu7SqjpaPnop2SUrlJHwBjU?= =?us-ascii?Q?UsKpEqJfSMxzvcmBL9Wn0YMLmlWefJraWnYiZWjHGdBmP3w0oZ5jvpMfVa/f?= =?us-ascii?Q?QbuigXOFTvlqeiWTwfm2dyu2BIGIbUxs6+OM8cqCL86MjovYrrA3lsyoFACY?= =?us-ascii?Q?rJw6AKmu5FIrgI/osk8DzgXY6NtCZk0lSOUcggXQy2/gSp/XvHeo5fi85GO2?= =?us-ascii?Q?YKeSFVHQQaNjatYp5rCVjCE3cXQY0mqFEFt3LfMz0jRrLivsRUEhwl0e8LV6?= =?us-ascii?Q?9/QYQWIl8bOvK+xahtqFYdPvoEgDTkv5lr9SduMV5LXjDkh2lfBX8IUaSiqs?= =?us-ascii?Q?GIJDehcQVTHNGDZce2RKcqjVAXx+e9Hz2oCcvZ5PUG4XHUJOxc+BD5FYp4U+?= =?us-ascii?Q?fC1xKimc1dvkPrmwiXFCXNljdLSME03J+YmNVBik5KWBbCeMBopM2+nXfhKe?= =?us-ascii?Q?+LQ+pZuC5H+ijW8h6c+JeAt1ZLAi4zGX56K6RbBDvfULNPU+XyLGoumH1ogN?= =?us-ascii?Q?Iq6DjwI2eWydEWE+Go2G5X9ZDIwwOmYfyAW9/ZyPF1WMynKVfIc1QXmua18f?= =?us-ascii?Q?8P6Z7HO4S//MpAJ2WBdwByoF5K1fpsP9U3wjNYHbATfSoXVSu4j95E7De/A/?= =?us-ascii?Q?IYkp7JY4yRQ+tltegDHk5QPwlMQIrhoJlaAX7GYJWteFplATSihcGF7ALnYF?= =?us-ascii?Q?XgOjdQE90LMLpqEEA45D9M9BxJYJRCTTISJA4GxBDUlmZZ6pwIMCMAlct4ZC?= =?us-ascii?Q?5n3EbL4ePOvT0gykdXXkQLZ3vXX/taNBbY2ad89Ld/sEZfMgV2XubcZZjyGw?= =?us-ascii?Q?jkETOXv2Z3mNbWIQqsiSoL+xb8FleohSc2aTBxgDK31YctoMuY31YUp4meZI?= =?us-ascii?Q?ig7AVFh4H3XEybUWeIUfBjQypdxg9mPRgHn8+54rL9aU4fQc9YcdM7/hX2Ik?= =?us-ascii?Q?TTBEQluQuc2B605Ljfe/aLOiwPhu2UmZ/B+xmqgJB9XXzIVCRfM9ncg916/Z?= =?us-ascii?Q?d0zqDZgcdQlNUfDJ4t9DuC8QGiCoAbqquE5FP8wUcDO8u11Vv0xDRVF5tXj2?= =?us-ascii?Q?AYOiV3zBWDPkv3jgMvwLWSo4y3nApthwE4SLgLRC7UDFd1lJVhFszWApUSzu?= =?us-ascii?Q?FN4ORBnhinPP+jpmBmow2o78yg9GokT6qb8AHXYtV6+TzTPL7i9R7iZsTjT7?= =?us-ascii?Q?WcZVW0GjF9f9lGRcbB5EEQNIIg1szpgvYfKrE3ptxOqFXG4THEKOh6haIh3v?= =?us-ascii?Q?FD0ma9owCftkpmlMs8fkEJmCd6gqKeyBrNW1iUAN5P9l4wxLeXmivG5mMa0j?= =?us-ascii?Q?9hZlIRx4q2L4anhOeRtghgJHr65zkMaf40vT5byiz7STR6BfDzMRHTbBqgzZ?= =?us-ascii?Q?faoDR0HoR0v4AtyisR9+bh+FLY04HimlyZJRQpP6xYhM97KCIErEh4faDj69?= =?us-ascii?Q?8zmqf+L97jC9bUzhQpi2Yb0QVjHcJXWKjWMIF+SWjdBsrQ3imVCUL9+DcvEE?= =?us-ascii?Q?WF/w1XVWOYzD7kO53iLUUm8y1sqMJ2rOQNQPQYjSiBTCZD4MXdsDhJFZ54UV?= =?us-ascii?Q?lXbQxnKqWWbrCexY4pla2iq7CwQu2yHswGTqWu21FBGo2sbZfylbCNnSTR5i?= =?us-ascii?Q?fnZLtaJNYSGFYqegQOVH6cC4yDdYjU2IkMab91c3J6FLLFJvYJmTj3oN0KCD?= =?us-ascii?Q?LvadiA=3D=3D?= X-OriginatorOrg: corigine.com X-MS-Exchange-CrossTenant-Network-Message-Id: 16b5fb33-65ba-4dcd-80d4-08db0921f60d X-MS-Exchange-CrossTenant-AuthSource: PH0PR13MB4842.namprd13.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 07 Feb 2023 15:42:47.1582 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: fe128f2c-073b-4c20-818e-7246a585940c X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: I0VB8Kud1y79HtmM5ridP7CZ9Utgyvf0phe04xne7/7J7Xp0FXv8dSD9XC/Yh4po+1++Zncg4JF7/6cxfO9qwmV17bOmiGs+nrrUp2rs+yA= X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ0PR13MB5846 Precedence: bulk List-ID: X-Mailing-List: linux-s390@vger.kernel.org On Mon, Feb 06, 2023 at 06:27:54PM +0100, Alexandra Winter wrote: > From: Thorsten Winkler > > This LWN article explains the rationale for this change > https: //lwn.net/Articles/69419/ https://lwn.net/Articles/69419/ > Ie. snprintf() returns what *would* be the resulting length, > while scnprintf() returns the actual length. Ok, but in most cases in this patch the return value is not checked. Is there any value in this change in those cases? > Reported-by: Jules Irenge > Reviewed-by: Alexandra Winkler s/Winkler/Winter/ ? > Signed-off-by: Thorsten Winkler > Signed-off-by: Alexandra Winter ... > diff --git a/drivers/s390/net/qeth_l3_main.c b/drivers/s390/net/qeth_l3_main.c > index 1cf4e354693f..af4e60d2917e 100644 > --- a/drivers/s390/net/qeth_l3_main.c > +++ b/drivers/s390/net/qeth_l3_main.c > @@ -47,9 +47,9 @@ int qeth_l3_ipaddr_to_string(enum qeth_prot_versions proto, const u8 *addr, > char *buf) > { > if (proto == QETH_PROT_IPV4) > - return sprintf(buf, "%pI4", addr); > + return scnprintf(buf, INET_ADDRSTRLEN, "%pI4", addr); > else > - return sprintf(buf, "%pI6", addr); > + return scnprintf(buf, INET6_ADDRSTRLEN, "%pI6", addr); > } This seems to be the once case where the return value is not ignored. Of the 4 callers of qeth_l3_ipaddr_to_string, two don't ignore the return value. And I agree in those cases this change seems correct. However, amongst other usages of the return value, those callers also check for a return < 0 from this function. Can that occur, in the sprintf or scnprintf case?