syzbot


BUG: unable to handle kernel NULL pointer dereference in read_cache_folio

Status: upstream: reported C repro on 2024/09/26 14:51
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+4089e577072948ac5531@syzkaller.appspotmail.com
First crash: 22d, last: 8d18h
Discussions (2)
Title Replies (including bot) Last reply
[PATCH v1] Fix NULL pointer dereference in read_cache_folio 6 (6) 2024/10/15 11:57
[syzbot] [fs?] BUG: unable to handle kernel NULL pointer dereference in read_cache_folio 0 (8) 2024/10/15 11:01
Last patch testing requests (8)
Created Duration User Patch Repo Result
2024/10/15 11:01 29m gianf.trad@gmail.com patch upstream OK log
2024/10/14 22:25 0m gianf.trad@gmail.com patch upstream error
2024/10/14 21:21 0m s323713@studenti.polito.it patch upstream error
2024/10/14 21:13 0m gianf.trad@gmail.com patch upstream error
2024/10/12 23:28 27m gianf.trad@gmail.com patch upstream OK log
2024/10/06 19:03 13m retest repro upstream report log
2024/09/30 08:32 27m s323713@studenti.polito.it patch upstream OK log
2024/09/29 22:29 28m gianf.trad@gmail.com patch upstream OK log

Sample crash report:
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
Mem abort info:
  ESR = 0x0000000086000006
  EC = 0x21: IABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x06: level 2 translation fault
user pgtable: 4k pages, 52-bit VAs, pgdp=00000000462cce00
[0000000000000000] pgd=080000004468e003, p4d=08000000466cc003, pud=0800000046cd6003, pmd=0000000000000000
Internal error: Oops: 0000000086000006 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 UID: 0 PID: 3265 Comm: syz-executor218 Tainted: G    B              6.11.0-syzkaller-08481-g88264981f208 #0
Tainted: [B]=BAD_PAGE
Hardware name: linux,dummy-virt (DT)
pstate: 61400809 (nZCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=-c)
pc : 0x0
lr : filemap_read_folio+0x44/0xf4 mm/filemap.c:2363
sp : ffff800088e6bac0
x29: ffff800088e6bac0 x28: f1f000000474e000 x27: 0000000020ffd000
x26: 0000000000000000 x25: 0000000000000000 x24: 0000000002100cca
x23: f6f0000006cd5c00 x22: 0000000000000000 x21: f6f0000006cd5c00
x20: 0000000000000000 x19: ffffc1ffc02e3300 x18: ffff800088e6bc20
x17: ffff8000804fee60 x16: ffff80008052fe10 x15: 0000000000000001
x14: 0000000000000000 x13: 0000000000000003 x12: 00000000000706a3
x11: 0000000000000001 x10: ffff800081f19060 x9 : 0000000000000000
x8 : fff07ffffd1f0000 x7 : fff000007f8e9d60 x6 : 0000000000000002
x5 : ffffc1ffc02e3300 x4 : 0000000000000000 x3 : faf0000005491240
x2 : 0000000000000000 x1 : ffffc1ffc02e3300 x0 : f6f0000006cd5c00
Call trace:
 0x0
 do_read_cache_folio+0x18c/0x29c mm/filemap.c:3821
 read_cache_folio+0x14/0x20 mm/filemap.c:3853
 freader_get_folio+0x1a8/0x1f8 lib/buildid.c:72
 freader_fetch+0x44/0x164 lib/buildid.c:115
 __build_id_parse.isra.0+0x98/0x2a8 lib/buildid.c:300
 build_id_parse+0x18/0x24 lib/buildid.c:354
 do_procmap_query+0x670/0x7a0 fs/proc/task_mmu.c:534
 procfs_procmap_ioctl+0x2c/0x44 fs/proc/task_mmu.c:613
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl fs/ioctl.c:893 [inline]
 __arm64_sys_ioctl+0xac/0xf0 fs/ioctl.c:893
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x48/0x110 arch/arm64/kernel/syscall.c:49
 el0_svc_common.constprop.0+0x40/0xe0 arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x1c/0x28 arch/arm64/kernel/syscall.c:151
 el0_svc+0x34/0xec arch/arm64/kernel/entry-common.c:712
 el0t_64_sync_handler+0x100/0x12c arch/arm64/kernel/entry-common.c:730
 el0t_64_sync+0x19c/0x1a0 arch/arm64/kernel/entry.S:598
Code: ???????? ???????? ???????? ???????? (????????) 
---[ end trace 0000000000000000 ]---

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/09/22 16:01 upstream 88264981f208 6f888b75 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-mte BUG: unable to handle kernel NULL pointer dereference in read_cache_folio
2024/09/22 19:03 upstream 88264981f208 6f888b75 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64 BUG: unable to handle kernel NULL pointer dereference in read_cache_folio
2024/09/22 19:02 upstream 88264981f208 6f888b75 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64 BUG: unable to handle kernel NULL pointer dereference in read_cache_folio
2024/09/22 14:42 upstream 88264981f208 6f888b75 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-mte BUG: unable to handle kernel NULL pointer dereference in read_cache_folio
2024/09/22 14:42 upstream 88264981f208 6f888b75 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-mte BUG: unable to handle kernel NULL pointer dereference in read_cache_folio
* Struck through repros no longer work on HEAD.