netdev - [PATCH net-next 2/3] net: sysctl: do not reserve an extra char in dump

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Message-ID: <20241017152422.487406-3-atenart@kernel.org>
Date: Thu, 17 Oct 2024 17:24:18 +0200
From: Antoine Tenart <atenart@...nel.org>
To: davem@...emloft.net,
	kuba@...nel.org,
	pabeni@...hat.com,
	edumazet@...gle.com
Cc: Antoine Tenart <atenart@...nel.org>,
	netdev@...r.kernel.org
Subject: [PATCH net-next 2/3] net: sysctl: do not reserve an extra char in dump_cpumask temporary buffer

When computing the length we'll be able to use out of the buffers, one
char is removed from the temporary one to make room for a newline. It
should be removed from the output buffer length too, but in reality this
is not needed as the later call to scnprintf makes sure a null char is
written at the end of the buffer which we override with the newline.

Signed-off-by: Antoine Tenart <atenart@...nel.org>
---
 net/core/sysctl_net_core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/core/sysctl_net_core.c b/net/core/sysctl_net_core.c
index e7c0121dfaa1..8dc07f7b1772 100644
--- a/net/core/sysctl_net_core.c
+++ b/net/core/sysctl_net_core.c
@@ -62,7 +62,7 @@ static void dump_cpumask(void *buffer, size_t *lenp, loff_t *ppos,
 		return;
 	}
 
-	len = min(sizeof(kbuf) - 1, *lenp);
+	len = min(sizeof(kbuf), *lenp);
 	len = scnprintf(kbuf, len, "%*pb", cpumask_pr_args(mask));
 	if (!len) {
 		*lenp = 0;
-- 
2.47.0