Re: general protection fault in wext_handle_ioctl

[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit:    e28c0d7c Merge branch 'akpm' (patches from Andrew)
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=15cd1cc2500000
kernel config:  https://syzkaller.appspot.com/x/.config?x=37bf5609aacce0b6
dashboard link: https://syzkaller.appspot.com/bug?extid=8b2a88a09653d4084179
compiler:       clang version 11.0.0 (https://github.com/llvm/llvm-project.git ca2dcbd030eadbf0aa9b660efe864ff08af6e18b)
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=13706da1500000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=10229fdc500000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+8b2a88a09653d4084179@xxxxxxxxxxxxxxxxxxxxxxxxx

general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 0 PID: 8462 Comm: syz-executor301 Not tainted 5.10.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:call_commit_handler net/wireless/wext-core.c:900 [inline]
RIP: 0010:ioctl_standard_call net/wireless/wext-core.c:1029 [inline]
RIP: 0010:wireless_process_ioctl net/wireless/wext-core.c:954 [inline]
RIP: 0010:wext_ioctl_dispatch net/wireless/wext-core.c:987 [inline]
RIP: 0010:wext_handle_ioctl+0x974/0xb20 net/wireless/wext-core.c:1048
Code: e8 61 1d a3 f8 eb 6c 48 8b 44 24 18 42 80 3c 20 00 48 8b 5c 24 20 74 08 48 89 df e8 26 16 e5 f8 48 8b 1b 48 89 d8 48 c1 e8 03 <42> 80 3c 20 00 74 08 48 89 df e8 0d 16 e5 f8 48 8b 1b 48 89 d8 48
RSP: 0018:ffffc9000143fe00 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff88d1ed88
RDX: ffff8880290e8000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffff88801b738000 R08: ffffffff88d1edaf R09: ffffed10036e7009
R10: ffffed10036e7009 R11: 0000000000000000 R12: dffffc0000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000008b04
FS:  0000000001eb8880(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd3b2be000 CR3: 0000000024723000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 sock_ioctl+0xdc/0x690 net/socket.c:1119
 vfs_ioctl fs/ioctl.c:48 [inline]
 __do_sys_ioctl fs/ioctl.c:753 [inline]
 __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:739
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x441529
Code: e8 ec 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 8b 0d fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffeab8016d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007ffeab801700 RCX: 0000000000441529
RDX: 00000000200000c0 RSI: 0000000000008b04 RDI: 0000000000000003
RBP: 0000000000000003 R08: 0000002000000000 R09: 0000002000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000032
R13: 0000000000000000 R14: 000000000000000c R15: 0000000000000004
Modules linked in:
---[ end trace d1b799cc496836f9 ]---
RIP: 0010:call_commit_handler net/wireless/wext-core.c:900 [inline]
RIP: 0010:ioctl_standard_call net/wireless/wext-core.c:1029 [inline]
RIP: 0010:wireless_process_ioctl net/wireless/wext-core.c:954 [inline]
RIP: 0010:wext_ioctl_dispatch net/wireless/wext-core.c:987 [inline]
RIP: 0010:wext_handle_ioctl+0x974/0xb20 net/wireless/wext-core.c:1048
Code: e8 61 1d a3 f8 eb 6c 48 8b 44 24 18 42 80 3c 20 00 48 8b 5c 24 20 74 08 48 89 df e8 26 16 e5 f8 48 8b 1b 48 89 d8 48 c1 e8 03 <42> 80 3c 20 00 74 08 48 89 df e8 0d 16 e5 f8 48 8b 1b 48 89 d8 48
RSP: 0018:ffffc9000143fe00 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff88d1ed88
RDX: ffff8880290e8000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffff88801b738000 R08: ffffffff88d1edaf R09: ffffed10036e7009
R10: ffffed10036e7009 R11: 0000000000000000 R12: dffffc0000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000008b04
FS:  0000000001eb8880(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd3b2be000 CR3: 0000000024723000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400