[syzbot] [kernel?] general protection fault in follow_pfnmap_start

From: syzbot
Date: Tue Oct 01 2024 - 05:37:40 EST

Hello,

syzbot found the following issue on:

HEAD commit: 075dbe9f6e3c Merge tag 'soc-ep93xx-dt-6.12' of git://git.k..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=17945e27980000
kernel config: https://syzkaller.appspot.com/x/.config?x=b2d4fdf18a83ec0b
dashboard link: https://syzkaller.appspot.com/bug?extid=093d096417e7038a689b
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=145dba80580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1703159f980000

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7feb34a89c2a/non_bootable_disk-075dbe9f.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/9c02adb371c0/vmlinux-075dbe9f.xz
kernel image: https://storage.googleapis.com/syzbot-assets/5e56aa110f69/bzImage-075dbe9f.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+093d096417e7038a689b@xxxxxxxxxxxxxxxxxxxxxxxxx

Oops: general protection fault, probably for non-canonical address 0xdffffc000000000b: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000058-0x000000000000005f]
CPU: 0 UID: 0 PID: 5102 Comm: syz-executor119 Not tainted 6.11.0-syzkaller-11558-g075dbe9f6e3c #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:pfnmap_lockdep_assert mm/memory.c:6349 [inline]
RIP: 0010:follow_pfnmap_start+0x1a7/0xfd0 mm/memory.c:6402
Code: 8d 9f 80 00 00 00 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 57 0c 1a 00 48 8b 1b 48 83 c3 58 48 89 d8 48 c1 e8 03 <42> 80 3c 20 00 74 08 48 89 df e8 3a 0c 1a 00 4c 8b 23 48 c7 c0 7c
RSP: 0018:ffffc9000179f100 EFLAGS: 00010202
RAX: 000000000000000b RBX: 0000000000000058 RCX: ffff88801aa0c880
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffc9000179f1e0
RBP: ffffc9000179f290 R08: ffffc9000179f311 R09: 0000000000000000
R10: ffffc9000179f2f0 R11: fffff520002f3e63 R12: dffffc0000000000
R13: 1ffff110023c0202 R14: ffffc9000179f2e0 R15: ffff888011e01000
FS: 0000555593c58380(0000) GS:ffff88801fc00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9ad1af10f0 CR3: 000000001270e000 CR4: 0000000000350ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
follow_phys arch/x86/mm/pat/memtype.c:956 [inline]
get_pat_info+0x182/0x3f0 arch/x86/mm/pat/memtype.c:988
untrack_pfn+0x327/0x640 arch/x86/mm/pat/memtype.c:1101
unmap_single_vma+0x1f6/0x2b0 mm/memory.c:1834
unmap_vmas+0x3cc/0x5f0 mm/memory.c:1900
unmap_region+0x214/0x380 mm/vma.c:354
mmap_region+0x22f9/0x2990 mm/mmap.c:1573
do_mmap+0x8f0/0x1000 mm/mmap.c:496
vm_mmap_pgoff+0x1dd/0x3d0 mm/util.c:588
ksys_mmap_pgoff+0x4eb/0x720 mm/mmap.c:542
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9ad1a7a879
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 c1 17 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd49b2ee58 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f9ad1a7a879
RDX: 0000000000000007 RSI: 0000000000005000 RDI: 0000000020371000
RBP: 00007f9ad1aed5f0 R08: 0000000000000003 R09: 0000000000000000
R10: 0000000000000011 R11: 0000000000000246 R12: 0000000000000001
R13: 431bde82d7b634db R14: 0000000000000001 R15: 0000000000000001
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:pfnmap_lockdep_assert mm/memory.c:6349 [inline]
RIP: 0010:follow_pfnmap_start+0x1a7/0xfd0 mm/memory.c:6402
Code: 8d 9f 80 00 00 00 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 57 0c 1a 00 48 8b 1b 48 83 c3 58 48 89 d8 48 c1 e8 03 <42> 80 3c 20 00 74 08 48 89 df e8 3a 0c 1a 00 4c 8b 23 48 c7 c0 7c
RSP: 0018:ffffc9000179f100 EFLAGS: 00010202
RAX: 000000000000000b RBX: 0000000000000058 RCX: ffff88801aa0c880
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffc9000179f1e0
RBP: ffffc9000179f290 R08: ffffc9000179f311 R09: 0000000000000000
R10: ffffc9000179f2f0 R11: fffff520002f3e63 R12: dffffc0000000000
R13: 1ffff110023c0202 R14: ffffc9000179f2e0 R15: ffff888011e01000
FS: 0000555593c58380(0000) GS:ffff88801fc00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555593c58ca8 CR3: 000000001270e000 CR4: 0000000000350ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: 8d 9f 80 00 00 00 lea 0x80(%rdi),%ebx
6: 48 89 d8 mov %rbx,%rax
9: 48 c1 e8 03 shr $0x3,%rax
d: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1)
12: 74 08 je 0x1c
14: 48 89 df mov %rbx,%rdi
17: e8 57 0c 1a 00 call 0x1a0c73
1c: 48 8b 1b mov (%rbx),%rbx
1f: 48 83 c3 58 add $0x58,%rbx
23: 48 89 d8 mov %rbx,%rax
26: 48 c1 e8 03 shr $0x3,%rax
* 2a: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1) <-- trapping instruction
2f: 74 08 je 0x39
31: 48 89 df mov %rbx,%rdi
34: e8 3a 0c 1a 00 call 0x1a0c73
39: 4c 8b 23 mov (%rbx),%r12
3c: 48 rex.W
3d: c7 .byte 0xc7
3e: c0 .byte 0xc0
3f: 7c .byte 0x7c


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