general protection fault in free_pages_and_swap_cache

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    b0c3ba31 Merge tag 'fsnotify_for_v5.7-rc8' of git://git.ke..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13ebe5e2100000
kernel config:  https://syzkaller.appspot.com/x/.config?x=cca7550d53ffa599
dashboard link: https://syzkaller.appspot.com/bug?extid=06f6ed6b0ea3f5d95cd1
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)

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

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+06f6ed6b0ea3f5d95cd1@xxxxxxxxxxxxxxxxxxxxxxxxx

general protection fault, probably for non-canonical address 0xdffffc00003d1339: 0000 [#1] PREEMPT SMP KASAN
KASAN: probably user-memory-access in range [0x0000000001e899c8-0x0000000001e899cf]
CPU: 0 PID: 29767 Comm: syz-executor.0 Not tainted 5.7.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__read_once_size include/linux/compiler.h:199 [inline]
RIP: 0010:compound_head include/linux/page-flags.h:182 [inline]
RIP: 0010:PageSwapCache include/linux/page-flags.h:391 [inline]
RIP: 0010:free_swap_cache mm/swap_state.c:267 [inline]
RIP: 0010:free_pages_and_swap_cache+0x94/0x3f0 mm/swap_state.c:295
Code: 00 00 e8 af 3c c9 ff 4c 89 e8 48 c1 e8 03 80 3c 18 00 0f 85 e8 02 00 00 4d 8b 65 00 49 8d 44 24 08 48 89 44 24 20 48 c1 e8 03 <80> 3c 18 00 0f 85 e7 02 00 00 4d 8b 7c 24 08 31 ff 4c 89 e5 4c 89
RSP: 0018:ffffc9001610f6c0 EFLAGS: 00010206
RAX: 00000000003d1339 RBX: dffffc0000000000 RCX: ffffffff81aa01e3
RDX: 0000000000000000 RSI: ffffffff81aa01f1 RDI: 0000000000000004
RBP: ffffea0001e89980 R08: ffff88803dc0a3c0 R09: fffff940003d1331
R10: ffffea0001e89987 R11: fffff940003d1330 R12: 0000000001e899c0
R13: ffff8880001a6898 R14: 0000000000000111 R15: 00000000000001fe
FS:  00007f0a0e9c6700(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b33326000 CR3: 00000000799e0000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 tlb_batch_pages_flush mm/mmu_gather.c:49 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:242 [inline]
 tlb_flush_mmu+0x8d/0x610 mm/mmu_gather.c:249
 zap_pte_range mm/memory.c:1158 [inline]
 zap_pmd_range mm/memory.c:1196 [inline]
 zap_pud_range mm/memory.c:1225 [inline]
 zap_p4d_range mm/memory.c:1246 [inline]
 unmap_page_range+0x198d/0x25d0 mm/memory.c:1267
 unmap_single_vma+0x196/0x300 mm/memory.c:1312
 unmap_vmas+0x16f/0x2f0 mm/memory.c:1344
 exit_mmap+0x2aa/0x510 mm/mmap.c:3150
 __mmput kernel/fork.c:1085 [inline]
 mmput+0x168/0x4b0 kernel/fork.c:1106
 exit_mm kernel/exit.c:480 [inline]
 do_exit+0xa51/0x2dd0 kernel/exit.c:783
 do_group_exit+0x125/0x340 kernel/exit.c:894
 get_signal+0x47b/0x24e0 kernel/signal.c:2739
 do_signal+0x81/0x2240 arch/x86/kernel/signal.c:784
 exit_to_usermode_loop+0x26c/0x360 arch/x86/entry/common.c:161
 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:279 [inline]
 do_syscall_64+0x6b1/0x7d0 arch/x86/entry/common.c:305
 entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x45ca29
Code: 0d b7 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 b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f0a0e9c5cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 000000000078bf08 RCX: 000000000045ca29
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000078bf08
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078bf0c
R13: 0000000000c9fb6f R14: 00007f0a0e9c69c0 R15: 000000000078bf0c
Modules linked in:
---[ end trace 5b99197ed4464cc6 ]---
RIP: 0010:__read_once_size include/linux/compiler.h:199 [inline]
RIP: 0010:compound_head include/linux/page-flags.h:182 [inline]
RIP: 0010:PageSwapCache include/linux/page-flags.h:391 [inline]
RIP: 0010:free_swap_cache mm/swap_state.c:267 [inline]
RIP: 0010:free_pages_and_swap_cache+0x94/0x3f0 mm/swap_state.c:295
Code: 00 00 e8 af 3c c9 ff 4c 89 e8 48 c1 e8 03 80 3c 18 00 0f 85 e8 02 00 00 4d 8b 65 00 49 8d 44 24 08 48 89 44 24 20 48 c1 e8 03 <80> 3c 18 00 0f 85 e7 02 00 00 4d 8b 7c 24 08 31 ff 4c 89 e5 4c 89
RSP: 0018:ffffc9001610f6c0 EFLAGS: 00010206
RAX: 00000000003d1339 RBX: dffffc0000000000 RCX: ffffffff81aa01e3
RDX: 0000000000000000 RSI: ffffffff81aa01f1 RDI: 0000000000000004
RBP: ffffea0001e89980 R08: ffff88803dc0a3c0 R09: fffff940003d1331
R10: ffffea0001e89987 R11: fffff940003d1330 R12: 0000000001e899c0
R13: ffff8880001a6898 R14: 0000000000000111 R15: 00000000000001fe
FS:  00007f0a0e9c6700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000021000000 CR3: 000000009d47f000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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