UBSAN: array-index-out-of-bounds in ieee80211_del_key (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    aae5ab85 Merge tag 'riscv-for-linus-5.10-rc6' of git://git..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1496d353500000
kernel config:  https://syzkaller.appspot.com/x/.config?x=cb8d1a3819ba4356
dashboard link: https://syzkaller.appspot.com/bug?extid=49d4cab497c2142ee170
compiler:       gcc (GCC) 10.1.0-syz 20200507
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=1440c58d500000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=1743351d500000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+49d4cab497c2142ee170@xxxxxxxxxxxxxxxxxxxxxxxxx

================================================================================
UBSAN: array-index-out-of-bounds in net/mac80211/cfg.c:520:10
index 5 is out of range for type 'ieee80211_key *[4]'
CPU: 0 PID: 8535 Comm: syz-executor933 Not tainted 5.10.0-rc5-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+0x107/0x163 lib/dump_stack.c:118
 ubsan_epilogue+0xb/0x5a lib/ubsan.c:148
 __ubsan_handle_out_of_bounds.cold+0x62/0x6c lib/ubsan.c:356
 ieee80211_del_key+0x3f6/0x440 net/mac80211/cfg.c:520
 rdev_del_key net/wireless/rdev-ops.h:107 [inline]
 nl80211_del_key+0x4b0/0x910 net/wireless/nl80211.c:4292
 genl_family_rcv_msg_doit+0x228/0x320 net/netlink/genetlink.c:739
 genl_family_rcv_msg net/netlink/genetlink.c:783 [inline]
 genl_rcv_msg+0x328/0x580 net/netlink/genetlink.c:800
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2494
 genl_rcv+0x24/0x40 net/netlink/genetlink.c:811
 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline]
 netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1330
 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:671
 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2353
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2407
 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2440
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x441ff9
Code: e8 ac 00 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 07 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffdb026c968 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000441ff9
RDX: 0000000000000000 RSI: 0000000020000300 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000002100000000 R09: 0000002100000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000032
R13: 0000000000000000 R14: 000000000000000c R15: 0000000000000004
================================================================================


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