mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-03 17:40:04 +00:00
![Eric Dumazet](/assets/img/avatar_default.png)
We already annotated most accesses to sk->sk_napi_id
We missed sk_mark_napi_id() and sk_mark_napi_id_once()
which might be called without socket lock held in UDP stack.
KCSAN reported :
BUG: KCSAN: data-race in udpv6_queue_rcv_one_skb / udpv6_queue_rcv_one_skb
write to 0xffff888121c6d108 of 4 bytes by interrupt on cpu 0:
sk_mark_napi_id include/net/busy_poll.h:125 [inline]
__udpv6_queue_rcv_skb net/ipv6/udp.c:571 [inline]
udpv6_queue_rcv_one_skb+0x70c/0xb40 net/ipv6/udp.c:672
udpv6_queue_rcv_skb+0xb5/0x400 net/ipv6/udp.c:689
udp6_unicast_rcv_skb.isra.0+0xd7/0x180 net/ipv6/udp.c:832
__udp6_lib_rcv+0x69c/0x1770 net/ipv6/udp.c:913
udpv6_rcv+0x2b/0x40 net/ipv6/udp.c:1015
ip6_protocol_deliver_rcu+0x22a/0xbe0 net/ipv6/ip6_input.c:409
ip6_input_finish+0x30/0x50 net/ipv6/ip6_input.c:450
NF_HOOK include/linux/netfilter.h:305 [inline]
NF_HOOK include/linux/netfilter.h:299 [inline]
ip6_input+0x177/0x190 net/ipv6/ip6_input.c:459
dst_input include/net/dst.h:442 [inline]
ip6_rcv_finish+0x110/0x140 net/ipv6/ip6_input.c:76
NF_HOOK include/linux/netfilter.h:305 [inline]
NF_HOOK include/linux/netfilter.h:299 [inline]
ipv6_rcv+0x1a1/0x1b0 net/ipv6/ip6_input.c:284
__netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:5010
__netif_receive_skb+0x37/0xf0 net/core/dev.c:5124
process_backlog+0x1d3/0x420 net/core/dev.c:5955
napi_poll net/core/dev.c:6392 [inline]
net_rx_action+0x3ae/0xa90 net/core/dev.c:6460
write to 0xffff888121c6d108 of 4 bytes by interrupt on cpu 1:
sk_mark_napi_id include/net/busy_poll.h:125 [inline]
__udpv6_queue_rcv_skb net/ipv6/udp.c:571 [inline]
udpv6_queue_rcv_one_skb+0x70c/0xb40 net/ipv6/udp.c:672
udpv6_queue_rcv_skb+0xb5/0x400 net/ipv6/udp.c:689
udp6_unicast_rcv_skb.isra.0+0xd7/0x180 net/ipv6/udp.c:832
__udp6_lib_rcv+0x69c/0x1770 net/ipv6/udp.c:913
udpv6_rcv+0x2b/0x40 net/ipv6/udp.c:1015
ip6_protocol_deliver_rcu+0x22a/0xbe0 net/ipv6/ip6_input.c:409
ip6_input_finish+0x30/0x50 net/ipv6/ip6_input.c:450
NF_HOOK include/linux/netfilter.h:305 [inline]
NF_HOOK include/linux/netfilter.h:299 [inline]
ip6_input+0x177/0x190 net/ipv6/ip6_input.c:459
dst_input include/net/dst.h:442 [inline]
ip6_rcv_finish+0x110/0x140 net/ipv6/ip6_input.c:76
NF_HOOK include/linux/netfilter.h:305 [inline]
NF_HOOK include/linux/netfilter.h:299 [inline]
ipv6_rcv+0x1a1/0x1b0 net/ipv6/ip6_input.c:284
__netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:5010
__netif_receive_skb+0x37/0xf0 net/core/dev.c:5124
process_backlog+0x1d3/0x420 net/core/dev.c:5955
Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 10890 Comm: syz-executor.0 Not tainted 5.4.0-rc3+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Fixes: e68b6e50fa
("udp: enable busy polling for all sockets")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
140 lines
3.2 KiB
C
140 lines
3.2 KiB
C
/* SPDX-License-Identifier: GPL-2.0-only */
|
|
/*
|
|
* net busy poll support
|
|
* Copyright(c) 2013 Intel Corporation.
|
|
*
|
|
* Author: Eliezer Tamir
|
|
*
|
|
* Contact Information:
|
|
* e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
|
|
*/
|
|
|
|
#ifndef _LINUX_NET_BUSY_POLL_H
|
|
#define _LINUX_NET_BUSY_POLL_H
|
|
|
|
#include <linux/netdevice.h>
|
|
#include <linux/sched/clock.h>
|
|
#include <linux/sched/signal.h>
|
|
#include <net/ip.h>
|
|
|
|
/* 0 - Reserved to indicate value not set
|
|
* 1..NR_CPUS - Reserved for sender_cpu
|
|
* NR_CPUS+1..~0 - Region available for NAPI IDs
|
|
*/
|
|
#define MIN_NAPI_ID ((unsigned int)(NR_CPUS + 1))
|
|
|
|
#ifdef CONFIG_NET_RX_BUSY_POLL
|
|
|
|
struct napi_struct;
|
|
extern unsigned int sysctl_net_busy_read __read_mostly;
|
|
extern unsigned int sysctl_net_busy_poll __read_mostly;
|
|
|
|
static inline bool net_busy_loop_on(void)
|
|
{
|
|
return sysctl_net_busy_poll;
|
|
}
|
|
|
|
static inline bool sk_can_busy_loop(const struct sock *sk)
|
|
{
|
|
return sk->sk_ll_usec && !signal_pending(current);
|
|
}
|
|
|
|
bool sk_busy_loop_end(void *p, unsigned long start_time);
|
|
|
|
void napi_busy_loop(unsigned int napi_id,
|
|
bool (*loop_end)(void *, unsigned long),
|
|
void *loop_end_arg);
|
|
|
|
#else /* CONFIG_NET_RX_BUSY_POLL */
|
|
static inline unsigned long net_busy_loop_on(void)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline bool sk_can_busy_loop(struct sock *sk)
|
|
{
|
|
return false;
|
|
}
|
|
|
|
#endif /* CONFIG_NET_RX_BUSY_POLL */
|
|
|
|
static inline unsigned long busy_loop_current_time(void)
|
|
{
|
|
#ifdef CONFIG_NET_RX_BUSY_POLL
|
|
return (unsigned long)(local_clock() >> 10);
|
|
#else
|
|
return 0;
|
|
#endif
|
|
}
|
|
|
|
/* in poll/select we use the global sysctl_net_ll_poll value */
|
|
static inline bool busy_loop_timeout(unsigned long start_time)
|
|
{
|
|
#ifdef CONFIG_NET_RX_BUSY_POLL
|
|
unsigned long bp_usec = READ_ONCE(sysctl_net_busy_poll);
|
|
|
|
if (bp_usec) {
|
|
unsigned long end_time = start_time + bp_usec;
|
|
unsigned long now = busy_loop_current_time();
|
|
|
|
return time_after(now, end_time);
|
|
}
|
|
#endif
|
|
return true;
|
|
}
|
|
|
|
static inline bool sk_busy_loop_timeout(struct sock *sk,
|
|
unsigned long start_time)
|
|
{
|
|
#ifdef CONFIG_NET_RX_BUSY_POLL
|
|
unsigned long bp_usec = READ_ONCE(sk->sk_ll_usec);
|
|
|
|
if (bp_usec) {
|
|
unsigned long end_time = start_time + bp_usec;
|
|
unsigned long now = busy_loop_current_time();
|
|
|
|
return time_after(now, end_time);
|
|
}
|
|
#endif
|
|
return true;
|
|
}
|
|
|
|
static inline void sk_busy_loop(struct sock *sk, int nonblock)
|
|
{
|
|
#ifdef CONFIG_NET_RX_BUSY_POLL
|
|
unsigned int napi_id = READ_ONCE(sk->sk_napi_id);
|
|
|
|
if (napi_id >= MIN_NAPI_ID)
|
|
napi_busy_loop(napi_id, nonblock ? NULL : sk_busy_loop_end, sk);
|
|
#endif
|
|
}
|
|
|
|
/* used in the NIC receive handler to mark the skb */
|
|
static inline void skb_mark_napi_id(struct sk_buff *skb,
|
|
struct napi_struct *napi)
|
|
{
|
|
#ifdef CONFIG_NET_RX_BUSY_POLL
|
|
skb->napi_id = napi->napi_id;
|
|
#endif
|
|
}
|
|
|
|
/* used in the protocol hanlder to propagate the napi_id to the socket */
|
|
static inline void sk_mark_napi_id(struct sock *sk, const struct sk_buff *skb)
|
|
{
|
|
#ifdef CONFIG_NET_RX_BUSY_POLL
|
|
WRITE_ONCE(sk->sk_napi_id, skb->napi_id);
|
|
#endif
|
|
sk_rx_queue_set(sk, skb);
|
|
}
|
|
|
|
/* variant used for unconnected sockets */
|
|
static inline void sk_mark_napi_id_once(struct sock *sk,
|
|
const struct sk_buff *skb)
|
|
{
|
|
#ifdef CONFIG_NET_RX_BUSY_POLL
|
|
if (!READ_ONCE(sk->sk_napi_id))
|
|
WRITE_ONCE(sk->sk_napi_id, skb->napi_id);
|
|
#endif
|
|
}
|
|
|
|
#endif /* _LINUX_NET_BUSY_POLL_H */
|