UBSAN: undefined-behaviour in ieee80211_del_key

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: b09c3451 Linux 4.19.149
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=12250f6b900000
kernel config: https://syzkaller.appspot.com/x/.config?x=d7c6dfb55644e8fd
dashboard link: https://syzkaller.appspot.com/bug?extid=f0e95380c225e3c9f1af
compiler: gcc (GCC) 10.1.0-syz 20200507

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f0e953...@syzkaller.appspotmail.com

================================================================================
UBSAN: Undefined behaviour in net/mac80211/cfg.c:491:9
index 255 is out of range for type 'ieee80211_key *[6]'
CPU: 1 PID: 10753 Comm: syz-executor.5 Not tainted 4.19.149-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+0x22c/0x33e lib/dump_stack.c:118
ubsan_epilogue+0xe/0x3a lib/ubsan.c:161
__ubsan_handle_out_of_bounds.cold+0x63/0x6f lib/ubsan.c:383
ieee80211_del_key+0x48a/0x490 net/mac80211/cfg.c:491
rdev_del_key net/wireless/rdev-ops.h:106 [inline]
nl80211_del_key+0x41e/0xc50 net/wireless/nl80211.c:3650
genl_family_rcv_msg+0x6bf/0xd50 net/netlink/genetlink.c:602
genl_rcv_msg+0xdf/0x1b0 net/netlink/genetlink.c:627
netlink_rcv_skb+0x160/0x440 net/netlink/af_netlink.c:2455
genl_rcv+0x24/0x40 net/netlink/genetlink.c:638
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x4d5/0x690 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x717/0xcc0 net/netlink/af_netlink.c:1909
sock_sendmsg_nosec net/socket.c:622 [inline]
sock_sendmsg+0xc7/0x130 net/socket.c:632
___sys_sendmsg+0x7bb/0x8f0 net/socket.c:2115
__sys_sendmsg net/socket.c:2153 [inline]
__do_sys_sendmsg net/socket.c:2162 [inline]
__se_sys_sendmsg net/socket.c:2160 [inline]
__x64_sys_sendmsg+0x132/0x220 net/socket.c:2160
do_syscall_64+0xf9/0x670 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45dd99
Code: 0d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f521cf2bc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 000000000002b140 RCX: 000000000045dd99
RDX: 0000000000000000 RSI: 0000000020000400 RDI: 0000000000000003
RBP: 000000000118bf60 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bf2c
R13: 00007ffd1a272c8f R14: 00007f521cf2c9c0 R15: 000000000118bf2c
================================================================================
netlink: 'syz-executor.0': attribute type 2 has an invalid length.
netlink: 'syz-executor.0': attribute type 1 has an invalid length.
netlink: 'syz-executor.4': attribute type 1 has an invalid length.
netlink: 'syz-executor.4': attribute type 1 has an invalid length.
can: request_module (can-proto-0) failed.
can: request_module (can-proto-0) failed.
mac80211_hwsim: wmediumd released netlink socket, switching to perfect channel medium
nf_conntrack: default automatic helper assignment has been turned off for security reasons and CT-based firewall rule not found. Use the iptables CT target to attach helpers instead.
mac80211_hwsim: wmediumd released netlink socket, switching to perfect channel medium
mac80211_hwsim: wmediumd released netlink socket, switching to perfect channel medium
mac80211_hwsim: wmediumd released netlink socket, switching to perfect channel medium
mac80211_hwsim: wmediumd released netlink socket, switching to perfect channel medium
mac80211_hwsim: wmediumd released netlink socket, switching to perfect channel medium
x_tables: duplicate underflow at hook 1


---
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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: b09c3451 Linux 4.19.149
git tree: linux-4.19.y

console output: https://syzkaller.appspot.com/x/log.txt?x=111ceedf900000

kernel config: https://syzkaller.appspot.com/x/.config?x=d7c6dfb55644e8fd
dashboard link: https://syzkaller.appspot.com/bug?extid=f0e95380c225e3c9f1af
compiler: gcc (GCC) 10.1.0-syz 20200507

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=124a3dcb900000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=102cbbbb900000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f0e953...@syzkaller.appspotmail.com

IPv6: ADDRCONF(NETDEV_UP): wlan1: link is not ready
wlan1: Created IBSS using preconfigured BSSID 50:50:50:50:50:50
wlan1: Creating new IBSS network, BSSID 50:50:50:50:50:50
IPv6: ADDRCONF(NETDEV_CHANGE): wlan1: link becomes ready

================================================================================
UBSAN: Undefined behaviour in net/mac80211/cfg.c:491:9
index 255 is out of range for type 'ieee80211_key *[6]'

CPU: 0 PID: 6486 Comm: syz-executor188 Not tainted 4.19.149-syzkaller #0

RIP: 0033:0x441759
Code: e8 dc 05 03 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b 0d fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fff3d5ebe68 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fff3d5ebe90 RCX: 0000000000441759

RDX: 0000000000000000 RSI: 0000000020000400 RDI: 0000000000000003

RBP: 0000000000000003 R08: 0000001d00000000 R09: 0000001d00000000