Re: [syzbot] [PATCH] Test for aea6bf908d73

[syzbot <syzbot+bbe84a4010eeea00982d@syzkaller.appspotmail.com>]

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Subject: [PATCH] Test for aea6bf908d73
Author: eadavis@qq.com

please test uaf in nfc_alloc_send_skb

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git aea6bf908d73

diff --git a/net/nfc/llcp_commands.c b/net/nfc/llcp_commands.c
index e2680a3bef79..05b21ced9e1f 100644
--- a/net/nfc/llcp_commands.c
+++ b/net/nfc/llcp_commands.c
@@ -754,6 +754,7 @@ int nfc_llcp_send_ui_frame(struct nfc_llcp_sock *sock, u8 ssap, u8 dsap,
 	remaining_len = len;
 	msg_ptr = msg_data;
 
+	bh_lock_sock(sock);
 	do {
 		remote_miu = sock->remote_miu > LLCP_MAX_MIU ?
 				local->remote_miu : sock->remote_miu;
@@ -784,6 +785,7 @@ int nfc_llcp_send_ui_frame(struct nfc_llcp_sock *sock, u8 ssap, u8 dsap,
 		remaining_len -= frag_len;
 		msg_ptr += frag_len;
 	} while (remaining_len > 0);
+	bh_unlock_sock(sock);
 
 	kfree(msg_data);
 
-- 
2.25.1