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From:   Xiaobo Liu <cppcoffee@gmail.com>
To:     davem@davemloft.net
Cc:     edumazet@google.com, kuba@kernel.org, pabeni@redhat.com,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        Xiaobo Liu <cppcoffee@gmail.com>
Subject: [PATCH] net/atm: fix proc_mpc_write 1 byte less calculated
Date:   Thu, 13 Oct 2022 23:19:01 +0800
Message-Id: <20221013151901.29368-1-cppcoffee@gmail.com>
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Then the input contains '\0' or '\n', proc_mpc_write has read them,
so the return value needs +1.

Signed-off-by: Xiaobo Liu <cppcoffee@gmail.com>
---
 net/atm/mpoa_proc.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/net/atm/mpoa_proc.c b/net/atm/mpoa_proc.c
index 829db9eba..444ceda60 100755
--- a/net/atm/mpoa_proc.c
+++ b/net/atm/mpoa_proc.c
@@ -224,8 +224,11 @@ static ssize_t proc_mpc_write(struct file *file, const char __user *buff,
 			free_page((unsigned long)page);
 			return -EFAULT;
 		}
-		if (*p == '\0' || *p == '\n')
+
+		if (*p == '\0' || *p == '\n') {
+			len += 1
 			break;
+		}
 	}
 
 	*p = '\0';
-- 
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