syzbot


BUG: unable to handle kernel NULL pointer dereference in device_find_child

Status: upstream: reported C repro on 2022/10/10 16:54
Reported-by: syzbot+6a462bc8fbe652f7d3fd@syzkaller.appspotmail.com
First crash: 57d, last: 36d

Sample crash report:
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000058
Mem abort info:
  ESR = 0x0000000096000006
  EC = 0x25: DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x06: level 2 translation fault
Data abort info:
  ISV = 0, ISS = 0x00000006
  CM = 0, WnR = 0
user pgtable: 4k pages, 48-bit VAs, pgdp=000000010b53c000
[0000000000000058] pgd=080000010b5e4003, p4d=080000010b5e4003, pud=0800000109b02003, pmd=0000000000000000
Internal error: Oops: 0000000096000006 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 3038 Comm: syz-executor292 Not tainted 6.0.0-rc7-syzkaller-18095-gbbed346d5a96 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/30/2022
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : klist_next+0x28/0x18c lib/klist.c:377
lr : klist_next+0x24/0x18c lib/klist.c:376
sp : ffff80001282ba10
x29: ffff80001282ba10 x28: ffff0000c10a3500 x27: 0001000000000000
x26: 0000000000000000 x25: 0000000000000000 x24: ffff0000c3f47000
x23: ffff80000d832b20 x22: ffff0000ca8a0000 x21: ffff0000c3f43538
x20: 0000000000000000 x19: ffff80001282ba68 x18: 00000000000000c0
x17: ffff80000dd0b198 x16: 0000000000000000 x15: 0000000000000000
x14: 0000000000000000 x13: 0000000000000002 x12: ffff80000d833180
x11: ff808000096ae804 x10: 0000000000000000 x9 : ffff8000096ae804
x8 : ffff0000c10a3500 x7 : ffff8000095d2cfc x6 : 0000000000000000
x5 : 0000000000000080 x4 : 0000000000000001 x3 : 0000000000000000
x2 : ffff80000b97020c x1 : ffff80001282ba68 x0 : 0000000000000000
Call trace:
 klist_next+0x28/0x18c lib/klist.c:377
 next_device drivers/base/core.c:3756 [inline]
 device_find_child+0x50/0x114 drivers/base/core.c:3899
 hci_conn_del_sysfs+0x54/0xfc net/bluetooth/hci_sysfs.c:71
 hci_conn_cleanup+0x2d4/0x380 net/bluetooth/hci_conn.c:147
 hci_conn_del+0x144/0x2a8 net/bluetooth/hci_conn.c:1022
 hci_conn_hash_flush+0xe8/0x148 net/bluetooth/hci_conn.c:2367
 hci_dev_close_sync+0x48c/0x9e0 net/bluetooth/hci_sync.c:4476
 hci_dev_do_close net/bluetooth/hci_core.c:554 [inline]
 hci_rfkill_set_block+0x98/0x198 net/bluetooth/hci_core.c:947
 rfkill_set_block+0xb4/0x1f8 net/rfkill/core.c:345
 rfkill_fop_write+0x358/0x3f8 net/rfkill/core.c:1286
 vfs_write+0x1a4/0x46c fs/read_write.c:576
 ksys_write+0xb4/0x160 fs/read_write.c:631
 __do_sys_write fs/read_write.c:643 [inline]
 __se_sys_write fs/read_write.c:640 [inline]
 __arm64_sys_write+0x24/0x34 fs/read_write.c:640
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall arch/arm64/kernel/syscall.c:52 [inline]
 el0_svc_common+0x138/0x220 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x48/0x164 arch/arm64/kernel/syscall.c:206
 el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:636
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:654
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581
Code: 910003fd aa0003f3 97afc505 a9405260 (f9402c18) 
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	910003fd 	mov	x29, sp
   4:	aa0003f3 	mov	x19, x0
   8:	97afc505 	bl	0xfffffffffebf141c
   c:	a9405260 	ldp	x0, x20, [x19]
* 10:	f9402c18 	ldr	x24, [x0, #88] <-- trapping instruction

Crashes (5):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-gce-arm64 2022/10/09 20:26 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci bbed346d5a96 aea5da89 .config log report syz C BUG: unable to handle kernel NULL pointer dereference in device_find_child
ci-upstream-gce-arm64 2022/10/07 22:37 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci bbed346d5a96 0de35f24 .config log report syz C BUG: unable to handle kernel NULL pointer dereference in device_find_child
ci-upstream-gce-arm64 2022/10/27 18:01 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci bbed346d5a96 86777b7f .config log report info BUG: unable to handle kernel NULL pointer dereference in device_find_child
ci-upstream-gce-arm64 2022/10/07 22:13 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci bbed346d5a96 0de35f24 .config log report info BUG: unable to handle kernel NULL pointer dereference in device_find_child
ci-upstream-gce-arm64 2022/10/07 16:16 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci bbed346d5a96 8a212197 .config log report info BUG: unable to handle kernel NULL pointer dereference in device_find_child
* Struck through repros no longer work on HEAD.