On Wed, Apr 5, 2023 at 2:39 AM Simon Horman <simon.horman@xxxxxxxxxxxx> wrote: > > On Tue, Apr 04, 2023 at 05:16:58PM +0000, Eric Dumazet wrote: > > syzbot reported a NULL dereference caused by a missing check > > in hwsim_pmsr_report_nl(), and bisected the issue to cited commit. > > > > v2: test the nlattr before using nla_data() on it (Simon Horman) > > > > general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN > > KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] > > CPU: 0 PID: 5084 Comm: syz-executor104 Not tainted 6.3.0-rc4-next-20230331-syzkaller #0 > > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023 > > RIP: 0010:jhash+0x339/0x610 include/linux/jhash.h:95 > > Code: 83 fd 01 0f 84 5f ff ff ff eb de 83 fd 05 74 3a e8 ac f5 71 fd 48 8d 7b 05 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 04 02 48 89 fa 83 e2 07 38 d0 7f 08 84 c0 0f 85 96 02 00 00 > > RSP: 0018:ffffc90003abf298 EFLAGS: 00010202 > > RAX: dffffc0000000000 RBX: 0000000000000004 RCX: 0000000000000000 > > RDX: 0000000000000001 RSI: ffffffff84111ba4 RDI: 0000000000000009 > > RBP: 0000000000000006 R08: 0000000000000005 R09: 000000000000000c > > R10: 0000000000000006 R11: 0000000000000000 R12: 000000004d2c27cd > > R13: 000000002bd9e6c2 R14: 000000002bd9e6c2 R15: 000000002bd9e6c2 > > FS: 0000555556847300(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 > > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > > CR2: 000000000045ad50 CR3: 0000000078aa6000 CR4: 00000000003506f0 > > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > > Call Trace: > > <TASK> > > rht_key_hashfn include/linux/rhashtable.h:159 [inline] > > __rhashtable_lookup include/linux/rhashtable.h:604 [inline] > > rhashtable_lookup include/linux/rhashtable.h:646 [inline] > > rhashtable_lookup_fast include/linux/rhashtable.h:672 [inline] > > get_hwsim_data_ref_from_addr+0xb9/0x600 drivers/net/wireless/virtual/mac80211_hwsim.c:757 > > hwsim_pmsr_report_nl+0xe7/0xd50 drivers/net/wireless/virtual/mac80211_hwsim.c:3764 > > genl_family_rcv_msg_doit.isra.0+0x1e6/0x2d0 net/netlink/genetlink.c:968 > > genl_family_rcv_msg net/netlink/genetlink.c:1048 [inline] > > genl_rcv_msg+0x4ff/0x7e0 net/netlink/genetlink.c:1065 > > netlink_rcv_skb+0x165/0x440 net/netlink/af_netlink.c:2572 > > genl_rcv+0x28/0x40 net/netlink/genetlink.c:1076 > > netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline] > > netlink_unicast+0x547/0x7f0 net/netlink/af_netlink.c:1365 > > netlink_sendmsg+0x925/0xe30 net/netlink/af_netlink.c:1942 > > sock_sendmsg_nosec net/socket.c:724 [inline] > > sock_sendmsg+0xde/0x190 net/socket.c:747 > > ____sys_sendmsg+0x71c/0x900 net/socket.c:2501 > > ___sys_sendmsg+0x110/0x1b0 net/socket.c:2555 > > __sys_sendmsg+0xf7/0x1c0 net/socket.c:2584 > > do_syscall_x64 arch/x86/entry/common.c:50 [inline] > > do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 > > entry_SYSCALL_64_after_hwframe+0x63/0xcd > > > > Fixes: 2af3b2a631b1 ("mac80211_hwsim: add PMSR report support via virtio") > > Reported-by: syzbot <syzkaller@xxxxxxxxxxxxxxxx> > > Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx> > > Cc: Jaewan Kim <jaewan@xxxxxxxxxx> > > Cc: Johannes Berg <johannes.berg@xxxxxxxxx> > > Thanks Eric, > > Reviewed-by: Simon Horman <simon.horman@xxxxxxxxxxxx> Reviewed-by: Jaewan Kim <jaewan@xxxxxxxxxx> -- Jaewan Kim (김재완) | Software Engineer in Google Korea | jaewan@xxxxxxxxxx | +82-10-2781-5078