8<--- cut here ---
Unable to handle kernel NULL pointer dereference at virtual address 0000000e when read
[0000000e] *pgd=854ab003
, *pmd
, *pmd=df741003
Internal error: Oops: 205 [#1] SMP ARM
Modules linked in:
CPU: 1 UID: 0 PID: 3839 Comm: syz.0.13 Not tainted 6.15.0-rc6-syzkaller #0 PREEMPT 
Hardware name: ARM-Versatile Express
PC is at io_ring_buffer_select io_uring/kbuf.c:163 [inline]
PC is at io_buffer_select+0x50/0x18c io_uring/kbuf.c:207
LR is at rcu_read_unlock include/linux/rcupdate.h:873 [inline]
LR is at xa_load+0x68/0xa4 lib/xarray.c:1621
pc : [<80889b64>]    lr : [<81a4c654>]    psr: 20000013
sp : dfee5de8  ip : dfee5da8  fp : dfee5e04
r10: 83479b80  r9 : 00000000  r8 : 80000001
r7 : dfee5e20  r6 : 00000000  r5 : 84c6e900  r4 : 854bb000
r3 : 00000001  r2 : 00000000  r1 : 854ba080  r0 : 00000000
Flags: nzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
Control: 30c5387d  Table: 854a6680  DAC: 00000000
Register r0 information: NULL pointer
Register r1 information: slab kmalloc-64 start 854ba080 pointer offset 0 size 64
Register r2 information: NULL pointer
Register r3 information: non-paged memory
Register r4 information: slab io_kiocb start 854bb000 pointer offset 0 size 192
Register r5 information: slab kmalloc-2k start 84c6e800 pointer offset 256 size 2048
Register r6 information: NULL pointer
Register r7 information: 2-page vmalloc region starting at 0xdfee4000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2844
Register r8 information: non-slab/vmalloc memory
Register r9 information: NULL pointer
Register r10 information: slab sock_inode_cache start 83479b80 pointer offset 0 size 576
Register r11 information: 2-page vmalloc region starting at 0xdfee4000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2844
Register r12 information: 2-page vmalloc region starting at 0xdfee4000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2844
Process syz.0.13 (pid: 3839, stack limit = 0xdfee4000)
Stack: (0xdfee5de8 to 0xdfee6000)
5de0:                   854bb000 854be900 00000000 00000040 dfee5e54 dfee5e08
5e00: 80892e90 80889b20 84211ac0 8280c8d4 00000000 00000001 01c01a40 00000000
5e20: 00000000 15845dac dfee5e54 854bb000 81cf0bd4 00000000 00000000 00000000
5e40: 80000001 84d6c800 dfee5e7c dfee5e58 80882314 80892c6c 854bb000 80000001
5e60: 0000000a 81cf0b5c 84d4e840 00000000 dfee5ebc dfee5e80 80886de4 808822d4
5e80: 84c6e800 854bb06c 854bb000 81cf0bd4 00000000 84c6e800 854bb06c 854bb000
5ea0: 858c0000 00000000 00000000 84d6c800 dfee5f14 dfee5ec0 808878fc 80886da8
5ec0: 8088e2b8 81a4c5f8 00000000 00000000 00000001 00000001 81cf0b5c 00000001
5ee0: 84c6e800 15845dac 84d4ec00 00000000 84c6e800 000027e2 84d4ec00 00000000
5f00: 84d6c800 00000000 dfee5fa4 dfee5f18 808883a4 808876fc ecac8b10 84c6e840
5f20: 00000000 00000000 81a503d0 81a502a0 dfee5f54 dfee5f40 8026b438 8029ce24
5f40: dfee5fb0 40000000 dfee5f84 dfee5f58 802229dc 8026b3f4 00000000 8281d05c
5f60: dfee5fb0 0014c490 ecac8b10 80222930 00000000 15845dac dfee5fac 00000000
5f80: 00000000 002e630c 000001aa 8020029c 84d6c800 000001aa 00000000 dfee5fa8
5fa0: 80200060 80888278 00000000 00000000 00000005 000027e2 00000000 00000000
5fc0: 00000000 00000000 002e630c 000001aa 002d0000 00000000 00006364 76b970bc
5fe0: 76b96ec0 76b96eb0 0001939c 00131f30 60000010 00000005 00000000 00000000
Call trace: 
[<80889b14>] (io_buffer_select) from [<80892e90>] (io_recvmsg+0x230/0x420 io_uring/net.c:988)
 r7:00000040 r6:00000000 r5:854be900 r4:854bb000
[<80892c60>] (io_recvmsg) from [<80882314>] (__io_issue_sqe+0x4c/0x1c0 io_uring/io_uring.c:1734)
 r10:84d6c800 r9:80000001 r8:00000000 r7:00000000 r6:00000000 r5:81cf0bd4
 r4:854bb000
[<808822c8>] (__io_issue_sqe) from [<80886de4>] (io_issue_sqe+0x48/0x59c io_uring/io_uring.c:1757)
 r9:00000000 r8:84d4e840 r7:81cf0b5c r6:0000000a r5:80000001 r4:854bb000
[<80886d9c>] (io_issue_sqe) from [<808878fc>] (io_queue_sqe io_uring/io_uring.c:1963 [inline])
[<80886d9c>] (io_issue_sqe) from [<808878fc>] (io_submit_sqe io_uring/io_uring.c:2219 [inline])
[<80886d9c>] (io_issue_sqe) from [<808878fc>] (io_submit_sqes+0x20c/0x938 io_uring/io_uring.c:2336)
 r10:84d6c800 r9:00000000 r8:00000000 r7:858c0000 r6:854bb000 r5:854bb06c
 r4:84c6e800
[<808876f0>] (io_submit_sqes) from [<808883a4>] (__do_sys_io_uring_enter io_uring/io_uring.c:3396 [inline])
[<808876f0>] (io_submit_sqes) from [<808883a4>] (sys_io_uring_enter+0x138/0x780 io_uring/io_uring.c:3330)
 r10:00000000 r9:84d6c800 r8:00000000 r7:84d4ec00 r6:000027e2 r5:84c6e800
 r4:00000000
[<8088826c>] (sys_io_uring_enter) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67)
Exception stack(0xdfee5fa8 to 0xdfee5ff0)
5fa0:                   00000000 00000000 00000005 000027e2 00000000 00000000
5fc0: 00000000 00000000 002e630c 000001aa 002d0000 00000000 00006364 76b970bc
5fe0: 76b96ec0 76b96eb0 0001939c 00131f30
 r10:000001aa r9:84d6c800 r8:8020029c r7:000001aa r6:002e630c r5:00000000
 r4:00000000
Code: e3130001 0a00002f e5910000 e1d120be (e1d030be) 
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	e3130001 	tst	r3, #1
   4:	0a00002f 	beq	0xc8
   8:	e5910000 	ldr	r0, [r1]
   c:	e1d120be 	ldrh	r2, [r1, #14]
* 10:	e1d030be 	ldrh	r3, [r0, #14] <-- trapping instruction