diff options
| author | Wei Wang <weiwan@google.com> | 2017-10-09 17:17:26 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-10-09 19:59:42 -0700 |
| commit | d0e60206bea2dec46c0a28fd6b116646aa67c5ae (patch) | |
| tree | fb44babe49eb7f69c1349cee373efc8cc39a22e6 /net/ipv6 | |
| parent | 9f7be893ab570e9d9b1287f99b35b30e6272efbf (diff) | |
ipv6: use rcu_dereference_bh() in ipv6_route_seq_next()
This patch replaces rcu_deference() with rcu_dereference_bh() in
ipv6_route_seq_next() to avoid the following warning:
[ 19.431685] WARNING: suspicious RCU usage
[ 19.433451] 4.14.0-rc3-00914-g66f5d6c #118 Not tainted
[ 19.435509] -----------------------------
[ 19.437267] net/ipv6/ip6_fib.c:2259 suspicious
rcu_dereference_check() usage!
[ 19.440790]
[ 19.440790] other info that might help us debug this:
[ 19.440790]
[ 19.444734]
[ 19.444734] rcu_scheduler_active = 2, debug_locks = 1
[ 19.447757] 2 locks held by odhcpd/3720:
[ 19.449480] #0: (&p->lock){+.+.}, at: [<ffffffffb1231f7d>]
seq_read+0x3c/0x333
[ 19.452720] #1: (rcu_read_lock_bh){....}, at: [<ffffffffb1d2b984>]
ipv6_route_seq_start+0x5/0xfd
[ 19.456323]
[ 19.456323] stack backtrace:
[ 19.458812] CPU: 0 PID: 3720 Comm: odhcpd Not tainted
4.14.0-rc3-00914-g66f5d6c #118
[ 19.462042] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS 1.10.2-1 04/01/2014
[ 19.465414] Call Trace:
[ 19.466788] dump_stack+0x86/0xc0
[ 19.468358] lockdep_rcu_suspicious+0xea/0xf3
[ 19.470183] ipv6_route_seq_next+0x71/0x164
[ 19.471963] seq_read+0x244/0x333
[ 19.473522] proc_reg_read+0x48/0x67
[ 19.475152] ? proc_reg_write+0x67/0x67
[ 19.476862] __vfs_read+0x26/0x10b
[ 19.478463] ? __might_fault+0x37/0x84
[ 19.480148] vfs_read+0xba/0x146
[ 19.481690] SyS_read+0x51/0x8e
[ 19.483197] do_int80_syscall_32+0x66/0x15a
[ 19.484969] entry_INT80_compat+0x32/0x50
[ 19.486707] RIP: 0023:0xf7f0be8e
[ 19.488244] RSP: 002b:00000000ffa75d04 EFLAGS: 00000246 ORIG_RAX:
0000000000000003
[ 19.491431] RAX: ffffffffffffffda RBX: 0000000000000009 RCX:
0000000008056068
[ 19.493886] RDX: 0000000000001000 RSI: 0000000008056008 RDI:
0000000000001000
[ 19.496331] RBP: 00000000000001ff R08: 0000000000000000 R09:
0000000000000000
[ 19.498768] R10: 0000000000000000 R11: 0000000000000000 R12:
0000000000000000
[ 19.501217] R13: 0000000000000000 R14: 0000000000000000 R15:
0000000000000000
Fixes: 66f5d6ce53e6 ("ipv6: replace rwlock with rcu and spinlock in fib6_table")
Reported-by: Xiaolong Ye <xiaolong.ye@intel.com>
Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv6')
| -rw-r--r-- | net/ipv6/ip6_fib.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c index 52a29ba32928..c2ecd5ec638a 100644 --- a/net/ipv6/ip6_fib.c +++ b/net/ipv6/ip6_fib.c @@ -2262,7 +2262,7 @@ static void *ipv6_route_seq_next(struct seq_file *seq, void *v, loff_t *pos) if (!v) goto iter_table; - n = rcu_dereference(((struct rt6_info *)v)->dst.rt6_next); + n = rcu_dereference_bh(((struct rt6_info *)v)->dst.rt6_next); if (n) { ++*pos; return n; |