4.14-stable review patch. If anyone has any objections, please let me know.
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From: Ursula Braun ubraun@linux.vnet.ibm.com
[ Upstream commit 1255fcb2a655f05e02f3a74675a6d6525f187afd ]
Calling shutdown with SHUT_RD and SHUT_RDWR for a listening SMC socket crashes, because commit 127f49705823 ("net/smc: release clcsock from tcp_listen_worker") releases the internal clcsock in smc_close_active() and sets smc->clcsock to NULL. For SHUT_RD the smc_close_active() call is removed. For SHUT_RDWR the kernel_sock_shutdown() call is omitted, since the clcsock is already released.
Fixes: 127f49705823 ("net/smc: release clcsock from tcp_listen_worker") Signed-off-by: Ursula Braun ubraun@linux.vnet.ibm.com Reported-by: Stephen Hemminger stephen@networkplumber.org Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/smc/af_smc.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-)
--- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -1203,14 +1203,12 @@ static int smc_shutdown(struct socket *s rc = smc_close_shutdown_write(smc); break; case SHUT_RD: - if (sk->sk_state == SMC_LISTEN) - rc = smc_close_active(smc); - else - rc = 0; - /* nothing more to do because peer is not involved */ + rc = 0; + /* nothing more to do because peer is not involved */ break; } - rc1 = kernel_sock_shutdown(smc->clcsock, how); + if (smc->clcsock) + rc1 = kernel_sock_shutdown(smc->clcsock, how); /* map sock_shutdown_cmd constants to sk_shutdown value range */ sk->sk_shutdown |= how + 1;