diff options
author | Eric Dumazet <edumazet@google.com> | 2018-10-26 19:33:27 +0300 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2018-10-27 02:03:51 +0300 |
commit | aab456dfa404f3a16d6f1780e62a6a8533c4d008 (patch) | |
tree | 0694ea386567f9b411c5d9f41aaa1ffe84bb5c97 /net/core/neighbour.c | |
parent | f64bf6b8ae802e93231155b0d92a619d896cd0bd (diff) | |
download | linux-aab456dfa404f3a16d6f1780e62a6a8533c4d008.tar.xz |
net/neigh: fix NULL deref in pneigh_dump_table()
pneigh can have NULL device pointer, so we need to make
neigh_master_filtered() and neigh_ifindex_filtered() more robust.
syzbot report :
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 15867 Comm: syz-executor2 Not tainted 4.19.0+ #276
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__read_once_size include/linux/compiler.h:179 [inline]
RIP: 0010:list_empty include/linux/list.h:203 [inline]
RIP: 0010:netdev_master_upper_dev_get+0xa1/0x250 net/core/dev.c:6467
RSP: 0018:ffff8801bfaf7220 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 0000000000000001 RCX: ffffc90005e92000
RDX: 0000000000000016 RSI: ffffffff860b44d9 RDI: 0000000000000005
RBP: ffff8801bfaf72b0 R08: ffff8801c4c84080 R09: fffffbfff139a580
R10: fffffbfff139a580 R11: ffffffff89cd2c07 R12: 1ffff10037f5ee45
R13: 0000000000000000 R14: ffff8801bfaf7288 R15: 00000000000000b0
FS: 00007f65cc68d700(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b33a21000 CR3: 00000001c6116000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
neigh_master_filtered net/core/neighbour.c:2367 [inline]
pneigh_dump_table net/core/neighbour.c:2456 [inline]
neigh_dump_info+0x7a9/0x1ce0 net/core/neighbour.c:2577
netlink_dump+0x606/0x1080 net/netlink/af_netlink.c:2244
__netlink_dump_start+0x59a/0x7c0 net/netlink/af_netlink.c:2352
netlink_dump_start include/linux/netlink.h:216 [inline]
rtnetlink_rcv_msg+0x809/0xc20 net/core/rtnetlink.c:4898
netlink_rcv_skb+0x172/0x440 net/netlink/af_netlink.c:2477
rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:4953
netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
netlink_unicast+0x5a5/0x760 net/netlink/af_netlink.c:1336
netlink_sendmsg+0xa18/0xfc0 net/netlink/af_netlink.c:1917
sock_sendmsg_nosec net/socket.c:621 [inline]
sock_sendmsg+0xd5/0x120 net/socket.c:631
sock_write_iter+0x35e/0x5c0 net/socket.c:900
call_write_iter include/linux/fs.h:1808 [inline]
new_sync_write fs/read_write.c:474 [inline]
__vfs_write+0x6b8/0x9f0 fs/read_write.c:487
vfs_write+0x1fc/0x560 fs/read_write.c:549
ksys_write+0x101/0x260 fs/read_write.c:598
__do_sys_write fs/read_write.c:610 [inline]
__se_sys_write fs/read_write.c:607 [inline]
__x64_sys_write+0x73/0xb0 fs/read_write.c:607
do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457569
Fixes: 6f52f80e8530 ("net/neigh: Extend dump filter to proxy neighbor dumps")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: David Ahern <dsahern@gmail.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Tested-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core/neighbour.c')
-rw-r--r-- | net/core/neighbour.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/net/core/neighbour.c b/net/core/neighbour.c index ee605d9d8bd4..41954e42a2de 100644 --- a/net/core/neighbour.c +++ b/net/core/neighbour.c @@ -2364,7 +2364,7 @@ static bool neigh_master_filtered(struct net_device *dev, int master_idx) if (!master_idx) return false; - master = netdev_master_upper_dev_get(dev); + master = dev ? netdev_master_upper_dev_get(dev) : NULL; if (!master || master->ifindex != master_idx) return true; @@ -2373,7 +2373,7 @@ static bool neigh_master_filtered(struct net_device *dev, int master_idx) static bool neigh_ifindex_filtered(struct net_device *dev, int filter_idx) { - if (filter_idx && dev->ifindex != filter_idx) + if (filter_idx && (!dev || dev->ifindex != filter_idx)) return true; return false; |