[syzbot] KASAN: use-after-free Read in unmap_page_range (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 1fc596a56b33 Merge tag 'trace-v5.15-rc6' of git://git.kern..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1173759ab00000
kernel config: https://syzkaller.appspot.com/x/.config?x=9646ff3aa1daf1a8
dashboard link: https://syzkaller.appspot.com/bug?extid=11210d36738191856de4
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15d15ad4b00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=142a0b64b00000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+11210d...@syzkaller.appspotmail.com

general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f]
CPU: 1 PID: 8652 Comm: syz-executor811 Not tainted 5.15.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__lock_acquire+0xd7d/0x54a0 kernel/locking/lockdep.c:4885
Code: e9 0d 41 be 01 00 00 00 0f 86 c8 00 00 00 89 05 f9 0b e9 0d e9 bd 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 <80> 3c 02 00 0f 85 f3 2f 00 00 48 81 3b 00 35 f0 8e 0f 84 52 f3 ff
RSP: 0018:ffffc9000562f970 EFLAGS: 00010006
RAX: dffffc0000000000 RBX: 0000000000000018 RCX: 0000000000000000
RDX: 0000000000000003 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff888077151c80 R14: 0000000000000000 R15: 0000000000000000
FS: 0000555555f75300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffdc1e38c38 CR3: 00000000780df000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
lock_acquire kernel/locking/lockdep.c:5625 [inline]
lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590
__raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
_raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
spin_lock include/linux/spinlock.h:363 [inline]
zap_pte_range mm/memory.c:1320 [inline]
zap_pmd_range mm/memory.c:1481 [inline]
zap_pud_range mm/memory.c:1510 [inline]
zap_p4d_range mm/memory.c:1531 [inline]
unmap_page_range+0x87b/0x2a10 mm/memory.c:1552
__oom_reap_task_mm+0x22d/0x400 mm/oom_kill.c:555
__do_sys_process_mrelease+0x32a/0x400 mm/oom_kill.c:1199
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7faa3e405d29
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 b1 14 00 00 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 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffdc1e38c38 EFLAGS: 00000246 ORIG_RAX: 00000000000001c0
RAX: ffffffffffffffda RBX: 0000000000011d9b RCX: 00007faa3e405d29
RDX: 00007faa3e405d29 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007ffdc1e38dd8 R09: 00007ffdc1e38dd8
R10: 00007ffdc1e38dd8 R11: 0000000000000246 R12: 00007ffdc1e38c4c
R13: 431bde82d7b634db R14: 0000000000000000 R15: 0000000000000000
Modules linked in:
---[ end trace 281cbdc141c02a9c ]---
RIP: 0010:__lock_acquire+0xd7d/0x54a0 kernel/locking/lockdep.c:4885
Code: e9 0d 41 be 01 00 00 00 0f 86 c8 00 00 00 89 05 f9 0b e9 0d e9 bd 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 <80> 3c 02 00 0f 85 f3 2f 00 00 48 81 3b 00 35 f0 8e 0f 84 52 f3 ff
RSP: 0018:ffffc9000562f970 EFLAGS: 00010006
RAX: dffffc0000000000 RBX: 0000000000000018 RCX: 0000000000000000
RDX: 0000000000000003 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff888077151c80 R14: 0000000000000000 R15: 0000000000000000
FS: 0000555555f75300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffdc1e38c38 CR3: 00000000780df000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess), 1 bytes skipped:
0: 0d 41 be 01 00 or $0x1be41,%eax
5: 00 00 add %al,(%rax)
7: 0f 86 c8 00 00 00 jbe 0xd5
d: 89 05 f9 0b e9 0d mov %eax,0xde90bf9(%rip) # 0xde90c0c
13: e9 bd 00 00 00 jmpq 0xd5
18: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
1f: fc ff df
22: 48 89 da mov %rbx,%rdx
25: 48 c1 ea 03 shr $0x3,%rdx
* 29: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction
2d: 0f 85 f3 2f 00 00 jne 0x3026
33: 48 81 3b 00 35 f0 8e cmpq $0xffffffff8ef03500,(%rbx)
3a: 0f .byte 0xf
3b: 84 52 f3 test %dl,-0xd(%rdx)
3e: ff .byte 0xff


---
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[Tetsuo Handa]

#syz fix: mm/oom_kill.c: prevent a race between process_mrelease and exit_mmap