From: Tao Chen <chen.dylane@linux.dev>
Date: Thu, 3 Jul 2025 16:37:00 +0000 (+0800)
Subject: bpf: Clean code with bpf_copy_to_user()
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3413bc0cf16e38db53830c837b4bf639fb2126ef;p=thirdparty%2Flinux.git

bpf: Clean code with bpf_copy_to_user()

No logic change, use bpf_copy_to_user() to clean code.

Signed-off-by: Tao Chen <chen.dylane@linux.dev>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20250703163700.677628-1-chen.dylane@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
---

diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 7db7182a30577..3f36bfe132660 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -5344,21 +5344,10 @@ static int bpf_task_fd_query_copy(const union bpf_attr *attr,
 
 			if (put_user(zero, ubuf))
 				return -EFAULT;
-		} else if (input_len >= len + 1) {
-			/* ubuf can hold the string with NULL terminator */
-			if (copy_to_user(ubuf, buf, len + 1))
-				return -EFAULT;
 		} else {
-			/* ubuf cannot hold the string with NULL terminator,
-			 * do a partial copy with NULL terminator.
-			 */
-			char zero = '\0';
-
-			err = -ENOSPC;
-			if (copy_to_user(ubuf, buf, input_len - 1))
-				return -EFAULT;
-			if (put_user(zero, ubuf + input_len - 1))
-				return -EFAULT;
+			err = bpf_copy_to_user(ubuf, buf, input_len, len);
+			if (err == -EFAULT)
+				return err;
 		}
 	}