From: Guo DaXing guodaxing@huawei.com
stable inclusion from stable-v5.10.83 commit 12ceb52f2cc49583394bad42a39468fde9d8e0cc bugzilla: 185879 https://gitee.com/openeuler/kernel/issues/I4QUVG
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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[ Upstream commit 9ebb0c4b27a6158303b791b5b91e66d7665ee30e ]
The kernel_listen function in smc_listen will fail when all the available ports are occupied. At this point smc->clcsock->sk->sk_data_ready has been changed to smc_clcsock_data_ready. When we call smc_listen again, now both smc->clcsock->sk->sk_data_ready and smc->clcsk_data_ready point to the smc_clcsock_data_ready function.
The smc_clcsock_data_ready() function calls lsmc->clcsk_data_ready which now points to itself resulting in an infinite loop.
This patch restores smc->clcsock->sk->sk_data_ready with the old value.
Fixes: a60a2b1e0af1 ("net/smc: reduce active tcp_listen workers") Signed-off-by: Guo DaXing guodaxing@huawei.com Acked-by: Tony Lu tonylu@linux.alibaba.com Signed-off-by: Karsten Graul kgraul@linux.ibm.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Chen Jun chenjun102@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- net/smc/af_smc.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index cfb5b9be0569..a0d3f4e07b06 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -1864,8 +1864,10 @@ static int smc_listen(struct socket *sock, int backlog) smc->clcsock->sk->sk_user_data = (void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY); rc = kernel_listen(smc->clcsock, backlog); - if (rc) + if (rc) { + smc->clcsock->sk->sk_data_ready = smc->clcsk_data_ready; goto out; + } sk->sk_max_ack_backlog = backlog; sk->sk_ack_backlog = 0; sk->sk_state = SMC_LISTEN;