diff options
| author | Eric Dumazet <edumazet@google.com> | 2019-04-13 17:32:21 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2019-04-14 13:43:17 -0700 |
| commit | c543cb4a5f07e09237ec0fc2c60c9f131b2c79ad (patch) | |
| tree | 32ee6941cd47c6798e3499725fdeb59c4df2fcf2 /net/ipv4 | |
| parent | ed0de45a1008991fdaa27a0152befcb74d126a8b (diff) | |
| download | linux-c543cb4a5f07e09237ec0fc2c60c9f131b2c79ad.tar.bz2 | |
ipv4: ensure rcu_read_lock() in ipv4_link_failure()
fib_compute_spec_dst() needs to be called under rcu protection.
syzbot reported :
WARNING: suspicious RCU usage
5.1.0-rc4+ #165 Not tainted
include/linux/inetdevice.h:220 suspicious rcu_dereference_check() usage!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
1 lock held by swapper/0/0:
#0: 0000000051b67925 ((&n->timer)){+.-.}, at: lockdep_copy_map include/linux/lockdep.h:170 [inline]
#0: 0000000051b67925 ((&n->timer)){+.-.}, at: call_timer_fn+0xda/0x720 kernel/time/timer.c:1315
stack backtrace:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.1.0-rc4+ #165
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
<IRQ>
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x172/0x1f0 lib/dump_stack.c:113
lockdep_rcu_suspicious+0x153/0x15d kernel/locking/lockdep.c:5162
__in_dev_get_rcu include/linux/inetdevice.h:220 [inline]
fib_compute_spec_dst+0xbbd/0x1030 net/ipv4/fib_frontend.c:294
spec_dst_fill net/ipv4/ip_options.c:245 [inline]
__ip_options_compile+0x15a7/0x1a10 net/ipv4/ip_options.c:343
ipv4_link_failure+0x172/0x400 net/ipv4/route.c:1195
dst_link_failure include/net/dst.h:427 [inline]
arp_error_report+0xd1/0x1c0 net/ipv4/arp.c:297
neigh_invalidate+0x24b/0x570 net/core/neighbour.c:995
neigh_timer_handler+0xc35/0xf30 net/core/neighbour.c:1081
call_timer_fn+0x190/0x720 kernel/time/timer.c:1325
expire_timers kernel/time/timer.c:1362 [inline]
__run_timers kernel/time/timer.c:1681 [inline]
__run_timers kernel/time/timer.c:1649 [inline]
run_timer_softirq+0x652/0x1700 kernel/time/timer.c:1694
__do_softirq+0x266/0x95a kernel/softirq.c:293
invoke_softirq kernel/softirq.c:374 [inline]
irq_exit+0x180/0x1d0 kernel/softirq.c:414
exiting_irq arch/x86/include/asm/apic.h:536 [inline]
smp_apic_timer_interrupt+0x14a/0x570 arch/x86/kernel/apic/apic.c:1062
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:807
Fixes: ed0de45a1008 ("ipv4: recompile ip options in ipv4_link_failure")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: Stephen Suryaputra <ssuryaextr@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4')
| -rw-r--r-- | net/ipv4/route.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/net/ipv4/route.c b/net/ipv4/route.c index 0206789bc2b7..88ce038dd495 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -1185,14 +1185,20 @@ static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie) static void ipv4_link_failure(struct sk_buff *skb) { - struct rtable *rt; struct ip_options opt; + struct rtable *rt; + int res; /* Recompile ip options since IPCB may not be valid anymore. */ memset(&opt, 0, sizeof(opt)); opt.optlen = ip_hdr(skb)->ihl*4 - sizeof(struct iphdr); - if (__ip_options_compile(dev_net(skb->dev), &opt, skb, NULL)) + + rcu_read_lock(); + res = __ip_options_compile(dev_net(skb->dev), &opt, skb, NULL); + rcu_read_unlock(); + + if (res) return; __icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0, &opt); |