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KASAN: vmalloc-out-of-bounds Read in __cfg8NUM_wpan_dev_from_attrs

Status: fixed on 2020/07/20 08:03
Subsystems: wpan
[Documentation on labels]
Reported-by: syzbot+b108a9b0cf438a20f4f8@syzkaller.appspotmail.com
Fix commit: bf64ff4c2aac genetlink: get rid of family->attrbuf
First crash: 1479d, last: 1464d
Discussions (1)
Title Replies (including bot) Last reply
KASAN: vmalloc-out-of-bounds Read in __cfg8NUM_wpan_dev_from_attrs 1 (2) 2020/06/30 03:50

Sample crash report:
netlink: 26 bytes leftover after parsing attributes in process `syz-executor.5'.
==================================================================
BUG: KASAN: vmalloc-out-of-bounds in nla_get_u32 include/net/netlink.h:1541 [inline]
BUG: KASAN: vmalloc-out-of-bounds in __cfg802154_wpan_dev_from_attrs+0x4b4/0x510 net/ieee802154/nl802154.c:53
Read of size 4 at addr ffffc90001ad9018 by task syz-executor.5/31529

CPU: 1 PID: 31529 Comm: syz-executor.5 Not tainted 5.8.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x18f/0x20d lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0x5/0x436 mm/kasan/report.c:383
 __kasan_report mm/kasan/report.c:513 [inline]
 kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530
 nla_get_u32 include/net/netlink.h:1541 [inline]
 __cfg802154_wpan_dev_from_attrs+0x4b4/0x510 net/ieee802154/nl802154.c:53
 nl802154_prepare_wpan_dev_dump.constprop.0+0xf9/0x490 net/ieee802154/nl802154.c:245
 nl802154_dump_llsec_dev+0xc0/0xb10 net/ieee802154/nl802154.c:1655
 genl_lock_dumpit+0x7f/0xb0 net/netlink/genetlink.c:575
 netlink_dump+0x4cd/0xf60 net/netlink/af_netlink.c:2245
 __netlink_dump_start+0x643/0x900 net/netlink/af_netlink.c:2353
 genl_family_rcv_msg_dumpit+0x2ac/0x310 net/netlink/genetlink.c:638
 genl_family_rcv_msg net/netlink/genetlink.c:733 [inline]
 genl_rcv_msg+0x797/0x9e0 net/netlink/genetlink.c:753
 netlink_rcv_skb+0x15a/0x430 net/netlink/af_netlink.c:2469
 genl_rcv+0x24/0x40 net/netlink/genetlink.c:764
 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline]
 netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1329
 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1918
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:672
 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2352
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2406
 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2439
 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:359
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45cb19
Code: Bad RIP value.
RSP: 002b:00007ff9558abc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000502400 RCX: 000000000045cb19
RDX: 0000000000000000 RSI: 0000000020000080 RDI: 0000000000000004
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000a38 R14: 00000000004cd1fc R15: 00007ff9558ac6d4


Memory state around the buggy address:
 ffffc90001ad8f00: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
 ffffc90001ad8f80: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
>ffffc90001ad9000: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
                            ^
 ffffc90001ad9080: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
 ffffc90001ad9100: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
==================================================================

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/06/27 00:51 bpf 7a64135f3229 aea82c00 .config console log report ci-upstream-bpf-kasan-gce
2020/06/26 12:48 bpf 7a64135f3229 aea82c00 .config console log report ci-upstream-bpf-kasan-gce
2020/07/11 09:59 bpf-next eef8a42d6ce0 18d18b59 .config console log report ci-upstream-bpf-next-kasan-gce
2020/06/27 11:23 net-next-old 7bed14551659 ffec44b5 .config console log report ci-upstream-net-kasan-gce
* Struck through repros no longer work on HEAD.