[syzbot] [net?] BUG: unable to handle kernel paging request in dst_dev_put (2)

[syzbot <syzbot+9911f8283beca191268b@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    7b1d1d4cfac0 Merge remote-tracking branch 'iommu/arm/smmu'..
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci
console output: https://syzkaller.appspot.com/x/log.txt?x=114ca75f980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=dfe1e340fbee3d16
dashboard link: https://syzkaller.appspot.com/bug?extid=9911f8283beca191268b
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: arm64

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/354fe38e2935/disk-7b1d1d4c.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f12e0b1ef3fd/vmlinux-7b1d1d4c.xz
kernel image: https://storage.googleapis.com/syzbot-assets/291dbc519bb3/Image-7b1d1d4c.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9911f8283beca191268b@syzkaller.appspotmail.com

Unable to handle kernel paging request at virtual address dfff800000000000
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
Mem abort info:
  ESR = 0x0000000096000005
  EC = 0x25: DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x05: level 1 translation fault
Data abort info:
  ISV = 0, ISS = 0x00000005, ISS2 = 0x00000000
  CM = 0, WnR = 0, TnD = 0, TagAccess = 0
  GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
[dfff800000000000] address between user and kernel address ranges
Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 UID: 0 PID: 16 Comm: ksoftirqd/0 Not tainted 6.12.0-syzkaller-g7b1d1d4cfac0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
pstate: 40400005 (nZcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : dst_dev_put+0x2c/0x2bc net/core/dst.c:146
lr : dst_dev_put+0x28/0x2bc net/core/dst.c:145
sp : ffff8000979379a0
x29: ffff8000979379a0 x28: ffffffffffffffff x27: ffff80008f16a000
x26: 1ffff00011e2d466 x25: dfff800000000000 x24: dfff800000000000
x23: 0000000000000000 x22: dfff800000000000 x21: ffff80008f821110
x20: 00007dfe9b881038 x19: 0000000000000002 x18: ffff0001b364a9a8
x17: 0000000000000040 x16: ffff800080585eb0 x15: 0000000000000001
x14: 1fffe0001df07cc3 x13: 0000000000000000 x12: 0000000000000000
x11: ffff60001df07cc4 x10: 0000000000ff0100 x9 : 0000000000000000
x8 : ffff0000c19e5ac0 x7 : ffff8000832ff164 x6 : 0000000000000000
x5 : 0000000000000001 x4 : 0000000000000001 x3 : ffff800089f54340
x2 : 0000000000000001 x1 : 0000000000000000 x0 : 0000000000000002
Call trace:
 dst_dev_put+0x2c/0x2bc net/core/dst.c:146 (P)
 dst_dev_put+0x28/0x2bc net/core/dst.c:145 (L)
 rt_fibinfo_free_cpus net/ipv4/fib_semantics.c:206 [inline]
 fib_nh_common_release+0x1f4/0x440 net/ipv4/fib_semantics.c:217
 fib6_nh_release+0x3a0/0x40c net/ipv6/route.c:3668
 fib6_info_destroy_rcu+0xc8/0x214 net/ipv6/ip6_fib.c:177
 rcu_do_batch kernel/rcu/tree.c:2567 [inline]
 rcu_core+0x898/0x1b5c kernel/rcu/tree.c:2823
 rcu_core_si+0x10/0x1c kernel/rcu/tree.c:2840
 handle_softirqs+0x2e0/0xbf8 kernel/softirq.c:554
 run_ksoftirqd+0x70/0xc0 kernel/softirq.c:949
 smpboot_thread_fn+0x4b0/0x90c kernel/smpboot.c:164
 kthread+0x288/0x310 kernel/kthread.c:389
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:862
Code: aa0003f3 f2fbfff6 97a314b2 d343fe77 (38766ae8) 
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	aa0003f3 	mov	x19, x0
   4:	f2fbfff6 	movk	x22, #0xdfff, lsl #48
   8:	97a314b2 	bl	0xfffffffffe8c52d0
   c:	d343fe77 	lsr	x23, x19, #3
* 10:	38766ae8 	ldrb	w8, [x23, x22] <-- trapping instruction


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