linux-kernel - [PATCH] fs: io_uring: remove NULL check before kfree

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Message-Id: <20220614091359.124571-1-dzm91@hust.edu.cn>
Date:   Tue, 14 Jun 2022 17:13:58 +0800
From:   Dongliang Mu <dzm91@...t.edu.cn>
To:     Jens Axboe <axboe@...nel.dk>,
        Pavel Begunkov <asml.silence@...il.com>
Cc:     mudongliang <mudongliangabcd@...il.com>, io-uring@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: [PATCH] fs: io_uring: remove NULL check before kfree

From: mudongliang <mudongliangabcd@...il.com>

kfree can handle NULL pointer as its argument.
According to coccinelle isnullfree check, remove NULL check
before kfree operation.

Signed-off-by: mudongliang <mudongliangabcd@...il.com>
---
 fs/io_uring.c | 15 +++++----------
 1 file changed, 5 insertions(+), 10 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 3aab4182fd89..bec47eae2a9b 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -3159,8 +3159,7 @@ static void io_free_batch_list(struct io_ring_ctx *ctx,
 			if ((req->flags & REQ_F_POLLED) && req->apoll) {
 				struct async_poll *apoll = req->apoll;
 
-				if (apoll->double_poll)
-					kfree(apoll->double_poll);
+				kfree(apoll->double_poll);
 				list_add(&apoll->poll.wait.entry,
 						&ctx->apoll_cache);
 				req->flags &= ~REQ_F_POLLED;
@@ -4499,8 +4498,7 @@ static int io_read(struct io_kiocb *req, unsigned int issue_flags)
 	kiocb_done(req, ret, issue_flags);
 out_free:
 	/* it's faster to check here then delegate to kfree */
-	if (iovec)
-		kfree(iovec);
+	kfree(iovec);
 	return 0;
 }
 
@@ -4602,8 +4600,7 @@ static int io_write(struct io_kiocb *req, unsigned int issue_flags)
 	}
 out_free:
 	/* it's reportedly faster than delegating the null check to kfree() */
-	if (iovec)
-		kfree(iovec);
+	kfree(iovec);
 	return ret;
 }
 
@@ -6227,8 +6224,7 @@ static int io_sendmsg(struct io_kiocb *req, unsigned int issue_flags)
 		req_set_fail(req);
 	}
 	/* fast path, check for non-NULL to avoid function call */
-	if (kmsg->free_iov)
-		kfree(kmsg->free_iov);
+	kfree(kmsg->free_iov);
 	req->flags &= ~REQ_F_NEED_CLEANUP;
 	if (ret >= 0)
 		ret += sr->done_io;
@@ -6481,8 +6477,7 @@ static int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags)
 	}
 
 	/* fast path, check for non-NULL to avoid function call */
-	if (kmsg->free_iov)
-		kfree(kmsg->free_iov);
+	kfree(kmsg->free_iov);
 	req->flags &= ~REQ_F_NEED_CLEANUP;
 	if (ret >= 0)
 		ret += sr->done_io;
-- 
2.35.1