From 1da992a0c59630acb6df9aec259cfb2df728112c Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Mon, 22 Jan 2024 11:25:55 +0000 Subject: sock_diag: annotate data-races around sock_diag_handlers[family] [ Upstream commit efd402537673f9951992aea4ef0f5ff51d858f4b ] __sock_diag_cmd() and sock_diag_bind() read sock_diag_handlers[family] without a lock held. Use READ_ONCE()/WRITE_ONCE() annotations to avoid potential issues. Fixes: 8ef874bfc729 ("sock_diag: Move the sock_ code to net/core/") Signed-off-by: Eric Dumazet Reviewed-by: Guillaume Nault Reviewed-by: Kuniyuki Iwashima Reviewed-by: Willem de Bruijn Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin --- net/core/sock_diag.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'net') diff --git a/net/core/sock_diag.c b/net/core/sock_diag.c index b1e29e18d1d6..c53b731f2d67 100644 --- a/net/core/sock_diag.c +++ b/net/core/sock_diag.c @@ -193,7 +193,7 @@ int sock_diag_register(const struct sock_diag_handler *hndl) if (sock_diag_handlers[hndl->family]) err = -EBUSY; else - sock_diag_handlers[hndl->family] = hndl; + WRITE_ONCE(sock_diag_handlers[hndl->family], hndl); mutex_unlock(&sock_diag_table_mutex); return err; @@ -209,7 +209,7 @@ void sock_diag_unregister(const struct sock_diag_handler *hnld) mutex_lock(&sock_diag_table_mutex); BUG_ON(sock_diag_handlers[family] != hnld); - sock_diag_handlers[family] = NULL; + WRITE_ONCE(sock_diag_handlers[family], NULL); mutex_unlock(&sock_diag_table_mutex); } EXPORT_SYMBOL_GPL(sock_diag_unregister); @@ -227,7 +227,7 @@ static int __sock_diag_cmd(struct sk_buff *skb, struct nlmsghdr *nlh) return -EINVAL; req->sdiag_family = array_index_nospec(req->sdiag_family, AF_MAX); - if (sock_diag_handlers[req->sdiag_family] == NULL) + if (READ_ONCE(sock_diag_handlers[req->sdiag_family]) == NULL) sock_load_diag_module(req->sdiag_family, 0); mutex_lock(&sock_diag_table_mutex); @@ -286,12 +286,12 @@ static int sock_diag_bind(struct net *net, int group) switch (group) { case SKNLGRP_INET_TCP_DESTROY: case SKNLGRP_INET_UDP_DESTROY: - if (!sock_diag_handlers[AF_INET]) + if (!READ_ONCE(sock_diag_handlers[AF_INET])) sock_load_diag_module(AF_INET, 0); break; case SKNLGRP_INET6_TCP_DESTROY: case SKNLGRP_INET6_UDP_DESTROY: - if (!sock_diag_handlers[AF_INET6]) + if (!READ_ONCE(sock_diag_handlers[AF_INET6])) sock_load_diag_module(AF_INET6, 0); break; } -- cgit v1.2.3