4.16-stable review patch. If anyone has any objections, please let me know.
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From: Ursula Braun ubraun@linux.ibm.com
[ Upstream commit 070204a34884110ac5e19c1e2e036fcfd033f8e3 ]
The internal CLC socket should exist till the SMC-socket is released. Function tcp_listen_worker() releases the internal CLC socket of a listen socket, if an smc_close_active() is called. This function is called for the final release(), but it is called for shutdown SHUT_RDWR as well. This opens a door for protection faults, if socket calls using the internal CLC socket are called for a shutdown listen socket.
With the changes of commit 3d502067599f ("net/smc: simplify wait when closing listen socket") there is no need anymore to release the internal CLC socket in function tcp_listen_worker((). It is sufficient to release it in smc_release().
Fixes: 127f49705823 ("net/smc: release clcsock from tcp_listen_worker") Signed-off-by: Ursula Braun ubraun@linux.ibm.com Reported-by: syzbot+9045fc589fcd196ef522@syzkaller.appspotmail.com Reported-by: syzbot+28a2c86cf19c81d871fa@syzkaller.appspotmail.com Reported-by: syzbot+9605e6cace1b5efd4a0a@syzkaller.appspotmail.com Reported-by: syzbot+cf9012c597c8379d535c@syzkaller.appspotmail.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/smc/af_smc.c | 4 ---- 1 file changed, 4 deletions(-)
--- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -973,10 +973,6 @@ static void smc_tcp_listen_work(struct w }
out: - if (lsmc->clcsock) { - sock_release(lsmc->clcsock); - lsmc->clcsock = NULL; - } release_sock(lsk); sock_put(&lsmc->sk); /* sock_hold in smc_listen */ }