Re: [syzbot] [PATCH] net/ipv4: Fixing circular deadlock

[syzbot <syzbot+e4c27043b9315839452d@syzkaller.appspotmail.com>]

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***

Subject: [PATCH] net/ipv4: Fixing circular deadlock
Author: srikarananta01@gmail.com

#syz test git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master

Fixed the circular lock dependency reported by syzkaller.

Signed-off-by: AnantaSrikar <srikarananta01@gmail.com>
Reported-by: syzbot+e4c27043b9315839452d@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=e4c27043b9315839452d
Fixes: d2bafcf224f3 ("Merge tag 'cgroup-for-6.11-rc4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup")
---
 net/ipv4/ip_sockglue.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index cf377377b52d..a8f46d1ba62b 100644
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -1073,9 +1073,11 @@ int do_ip_setsockopt(struct sock *sk, int level, int optname,
 	}
 
 	err = 0;
+
+	sockopt_lock_sock(sk);
+
 	if (needs_rtnl)
 		rtnl_lock();
-	sockopt_lock_sock(sk);
 
 	switch (optname) {
 	case IP_OPTIONS:
-- 
2.43.0