syzbot


BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio (3)

Status: moderation: reported on 2024/08/18 13:26
Subsystems: mm
[Documentation on labels]
Reported-by: syzbot+3c26aa13d4fb6a5b602f@syzkaller.appspotmail.com
First crash: 29d, last: 29d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio fs mm 8 683d 693d 0/27 auto-obsoleted due to no activity on 2023/02/26 19:26
upstream BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio (2) fs 6 457d 507d 0/27 auto-obsoleted due to no activity on 2023/09/20 22:50

Sample crash report:
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor instruction fetch in kernel mode
#PF: error_code(0x0010) - not-present page
PGD 462ec067 P4D 462ec067 PUD 462ed067 PMD 0 
Oops: Oops: 0010 [#1] PREEMPT SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 5123 Comm: syz.0.0 Not tainted 6.11.0-rc3-syzkaller-00013-g6b0f8db921ab #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:0x0
Code: Unable to access opcode bytes at 0xffffffffffffffd6.
RSP: 0018:ffffc9000ba268f8 EFLAGS: 00010293
RAX: ffffffff81cb1d40 RBX: 0000000000000000 RCX: ffff88801b748000
RDX: 0000000000000000 RSI: ffffea0000821700 RDI: ffff88801292aa00
RBP: ffffc9000ba269b0 R08: ffffea0000821707 R09: 1ffffd40001042e0
R10: dffffc0000000000 R11: 0000000000000000 R12: ffffea0000821700
R13: 1ffffd40001042e1 R14: 0000000000000000 R15: ffffea0000821708
FS:  00007fbf20f7a6c0(0000) GS:ffff888020800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000000463ea000 CR4: 0000000000350ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 filemap_read_folio+0x1a0/0x790 mm/filemap.c:2355
 filemap_fault+0xf69/0x1760 mm/filemap.c:3406
 __do_fault+0x135/0x460 mm/memory.c:4655
 do_read_fault mm/memory.c:5061 [inline]
 do_fault mm/memory.c:5191 [inline]
 do_pte_missing mm/memory.c:3947 [inline]
 handle_pte_fault+0x3b24/0x6eb0 mm/memory.c:5522
 __handle_mm_fault mm/memory.c:5665 [inline]
 handle_mm_fault+0x1029/0x1980 mm/memory.c:5833
 faultin_page mm/gup.c:1194 [inline]
 __get_user_pages+0x6ec/0x16a0 mm/gup.c:1493
 __get_user_pages_locked mm/gup.c:1760 [inline]
 get_dump_page+0x155/0x2f0 mm/gup.c:2278
 dump_user_range+0x14c/0x950 fs/coredump.c:952
 elf_core_dump+0x3de6/0x4720 fs/binfmt_elf.c:2116
 do_coredump+0x1b04/0x2a30 fs/coredump.c:767
 get_signal+0x13fa/0x1740 kernel/signal.c:2902
 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 irqentry_exit_to_user_mode+0x79/0x280 kernel/entry/common.c:231
 exc_page_fault+0x590/0x8c0 arch/x86/mm/fault.c:1542
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x0
Code: Unable to access opcode bytes at 0xffffffffffffffd6.
RSP: 002b:0000000020000048 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007fbf20315f80 RCX: 00007fbf201799f9
RDX: 00000000200000c0 RSI: 0000000020000040 RDI: 0000000000000400
RBP: 00007fbf201e78ee R08: 0000000020000180 R09: 0000000020000180
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fbf20315f80 R15: 00007fff12df3c98
 </TASK>
Modules linked in:
CR2: 0000000000000000
---[ end trace 0000000000000000 ]---
RIP: 0010:0x0
Code: Unable to access opcode bytes at 0xffffffffffffffd6.
RSP: 0018:ffffc9000ba268f8 EFLAGS: 00010293
RAX: ffffffff81cb1d40 RBX: 0000000000000000 RCX: ffff88801b748000
RDX: 0000000000000000 RSI: ffffea0000821700 RDI: ffff88801292aa00
RBP: ffffc9000ba269b0 R08: ffffea0000821707 R09: 1ffffd40001042e0
R10: dffffc0000000000 R11: 0000000000000000 R12: ffffea0000821700
R13: 1ffffd40001042e1 R14: 0000000000000000 R15: ffffea0000821708
FS:  00007fbf20f7a6c0(0000) GS:ffff888020800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000000463ea000 CR4: 0000000000350ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/08/14 13:24 upstream 6b0f8db921ab 890d2dda .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
* Struck through repros no longer work on HEAD.