netdev - [PATCH net-next 3/8] mptcp: pm: Return local variable instead of freed pointer

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Message-Id: <20250411-net-next-mptcp-sched-mib-sft-misc-v1-3-85ac8c6654c3@kernel.org>
Date: Fri, 11 Apr 2025 13:04:49 +0200
From: "Matthieu Baerts (NGI0)" <matttbe@...nel.org>
To: mptcp@...ts.linux.dev, Mat Martineau <martineau@...nel.org>, 
 Geliang Tang <geliang@...nel.org>, "David S. Miller" <davem@...emloft.net>, 
 Eric Dumazet <edumazet@...gle.com>, Jakub Kicinski <kuba@...nel.org>, 
 Paolo Abeni <pabeni@...hat.com>, Simon Horman <horms@...nel.org>, 
 Shuah Khan <shuah@...nel.org>
Cc: netdev@...r.kernel.org, linux-kernel@...r.kernel.org, 
 linux-kselftest@...r.kernel.org, 
 "Matthieu Baerts (NGI0)" <matttbe@...nel.org>, 
 Thorsten Blum <thorsten.blum@...ux.dev>
Subject: [PATCH net-next 3/8] mptcp: pm: Return local variable instead of
 freed pointer

From: Thorsten Blum <thorsten.blum@...ux.dev>

Commit e4c28e3d5c090 ("mptcp: pm: move generic PM helpers to pm.c")
removed an unnecessary if-check, which resulted in returning a freed
pointer.

This still works due to the implicit boolean conversion when returning
the freed pointer from mptcp_remove_anno_list_by_saddr(), but it can be
confusing and potentially error-prone. To improve clarity, add a local
variable to explicitly return a boolean value instead.

Signed-off-by: Thorsten Blum <thorsten.blum@...ux.dev>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@...nel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@...nel.org>
---
Notes:
- a previous version has already been sent to Netdev. ChangeLog:
  - Remove the if-check again as suggested by Matthieu Baerts
  - Target net-next, not net (not a fix) and rephrase the commit message
  - Link to this version:
    https://lore.kernel.org/20250325110639.49399-2-thorsten.blum@linux.dev
---
 net/mptcp/pm.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/net/mptcp/pm.c b/net/mptcp/pm.c
index 31747f974941fae3f80bfc8313e82c41f92562eb..1306d4dc287b842ebf7efd52d121b096d5cb43e0 100644
--- a/net/mptcp/pm.c
+++ b/net/mptcp/pm.c
@@ -151,10 +151,13 @@ bool mptcp_remove_anno_list_by_saddr(struct mptcp_sock *msk,
 				     const struct mptcp_addr_info *addr)
 {
 	struct mptcp_pm_add_entry *entry;
+	bool ret;

 	entry = mptcp_pm_del_add_timer(msk, addr, false);
+	ret = entry;
 	kfree(entry);
-	return entry;
+
+	return ret;
 }

 bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk)

-- 
2.48.1