Re: [syzbot] [nvme?] BUG: corrupted list in nvmet_fc_remove_port

[Hillf Danton]

> Date: Sun, 11 Oct 2026 10:32:37 -0700	[thread overview]
> Hello,
> 
> syzbot found the following issue on:
> 
> HEAD commit:    a5ebb76233b7 Merge tag 'edac_urgent_for_v7.3_rc7' of git:/..
> git tree:       upstream
> console+strace: https://syzkaller.appspot.com/x/log.txt?x=1494923e580000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=df4bbab1c2172b9f
> dashboard link: https://syzkaller.appspot.com/bug?extid=c98b21427617af7f547a
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=126a0f15580000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=166a0f15580000

#syz test

--- x/drivers/nvme/target/fc.c
+++ y/drivers/nvme/target/fc.c
@@ -1620,6 +1620,7 @@ nvmet_fc_free_pending_reqs(struct nvmet_
 	}
 }
 
+static DEFINE_MUTEX(tgtp_mutex);
 /**
  * nvmet_fc_unregister_targetport - transport entry point called by an
  *                              LLDD to deregister/remove a previously
@@ -1637,6 +1638,7 @@ nvmet_fc_unregister_targetport(struct nv
 	struct nvmet_fc_tgtport *tgtport = targetport_to_tgtport(target_port);
 	unsigned long flags;
 
+	mutex_lock(&tgtp_mutex);
 	spin_lock_irqsave(&nvmet_fc_tgtlock, flags);
 	list_del(&tgtport->tgt_list);
 	spin_unlock_irqrestore(&nvmet_fc_tgtlock, flags);
@@ -1645,6 +1647,7 @@ nvmet_fc_unregister_targetport(struct nv
 
 	/* terminate any outstanding associations */
 	__nvmet_fc_free_assocs(tgtport);
+	mutex_unlock(&tgtp_mutex);
 
 	flush_workqueue(nvmet_wq);
 
@@ -2919,6 +2922,7 @@ nvmet_fc_remove_port(struct nvmet_port *
 	struct nvmet_fc_tgtport *tgtport = NULL;
 	unsigned long flags;
 
+	mutex_lock(&tgtp_mutex);
 	spin_lock_irqsave(&nvmet_fc_tgtlock, flags);
 	if (pe->tgtport && nvmet_fc_tgtport_get(pe->tgtport))
 		tgtport = pe->tgtport;
@@ -2933,6 +2937,7 @@ nvmet_fc_remove_port(struct nvmet_port *
 	}
 
 	kfree(pe);
+	mutex_unlock(&tgtp_mutex);
 }
 
 static void
--