From 1ad24058335427d046b2e5666bcd15a62ad9e242 Mon Sep 17 00:00:00 2001 From: Karsten Graul Date: Sat, 18 Jul 2020 15:06:18 +0200 Subject: net/smc: fix restoring of fallback changes When a listen socket is closed then all non-accepted sockets in its accept queue are to be released. Inside __smc_release() the helper smc_restore_fallback_changes() restores the changes done to the socket without to check if the clcsocket has a file set. This can result in a crash. Fix this by checking the file pointer first. Reviewed-by: Ursula Braun Fixes: f536dffc0b79 ("net/smc: fix closing of fallback SMC sockets") Signed-off-by: Karsten Graul Signed-off-by: David S. Miller --- net/smc/af_smc.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'net/smc') diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index d091509b5982..1163d51196da 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -126,8 +126,10 @@ EXPORT_SYMBOL_GPL(smc_proto6); static void smc_restore_fallback_changes(struct smc_sock *smc) { - smc->clcsock->file->private_data = smc->sk.sk_socket; - smc->clcsock->file = NULL; + if (smc->clcsock->file) { /* non-accepted sockets have no file yet */ + smc->clcsock->file->private_data = smc->sk.sk_socket; + smc->clcsock->file = NULL; + } } static int __smc_release(struct smc_sock *smc) -- cgit v1.2.3