8<--- cut here ---
Unable to handle kernel NULL pointer dereference at virtual address 0000000e when read
[0000000e] *pgd=8503b003, *pmd=df609003
Internal error: Oops: 205 [#1] SMP ARM
Modules linked in:
CPU: 0 UID: 0 PID: 4075 Comm: syz.0.69 Not tainted 6.15.0-rc5-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 : [<80889a10>]    lr : [<81a4be34>]    psr: 20000013
sp : dfbd5e18  ip : dfbd5dd8  fp : dfbd5e34
r10: 84c98f00  r9 : 00000000  r8 : 80000001
r7 : dfbd5e50  r6 : 00000000  r5 : 85443100  r4 : 8503a000
r3 : 00000001  r2 : 00000000  r1 : 855a6180  r0 : 00000000
Flags: nzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
Control: 30c5387d  Table: 855a6280  DAC: fffffffd
Register r0 information: NULL pointer
Register r1 information: slab kmalloc-64 start 855a6180 pointer offset 0 size 64
Register r2 information: NULL pointer
Register r3 information: non-paged memory
Register r4 information: slab io_kiocb start 8503a000 pointer offset 0 size 192
Register r5 information: slab kmalloc-2k start 85443000 pointer offset 256 size 2048
Register r6 information: NULL pointer
Register r7 information: 2-page vmalloc region starting at 0xdfbd4000 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 84c98f00 pointer offset 0 size 576
Register r11 information: 2-page vmalloc region starting at 0xdfbd4000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2844
Register r12 information: 2-page vmalloc region starting at 0xdfbd4000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2844
Process syz.0.69 (pid: 4075, stack limit = 0xdfbd4000)
Stack: (0xdfbd5e18 to 0xdfbd6000)
5e00:                                                       8503a000 854a2a00
5e20: 00000000 00000040 dfbd5e84 dfbd5e38 80892d3c 808899cc 8057abbc 8030cb0c
5e40: 8503a000 00000001 0103a000 00000000 00000020 18a06e43 80886a40 8503a000
5e60: 81cf0bd4 00000000 80000001 81cf0b5c 0000000a 83b81800 dfbd5ebc dfbd5e88
5e80: 80886df4 80892b18 00000000 00000000 00000000 85443000 8503a06c 8503a000
5ea0: 84674000 00000000 00000000 83b81800 dfbd5f14 dfbd5ec0 808877a8 80886b7c
5ec0: 8088e164 81a4bdd8 dfbd5f24 dfbd5ed8 00000001 00000001 81cf0b5c 00000001
5ee0: 85443000 18a06e43 84996b40 00000000 85443000 000027e2 84996b40 00000000
5f00: 83b81800 00000000 dfbd5fa4 dfbd5f18 80888250 808875a8 ecac8b10 85443040
5f20: 00000000 00000000 81a4fbb0 81a4fa80 dfbd5f54 dfbd5f40 8026b438 8029ce1c
5f40: dfbd5fb0 40000000 dfbd5f84 dfbd5f58 802229dc 8026b3f4 00000000 8281d05c
5f60: dfbd5fb0 0014c490 ecac8b10 80222930 00000000 18a06e43 dfbd5fac 00000000
5f80: 00000000 002e630c 000001aa 8020029c 83b81800 000001aa 00000000 dfbd5fa8
5fa0: 80200060 80888124 00000000 00000000 00000003 000027e2 00000000 00000000
5fc0: 00000000 00000000 002e630c 000001aa 002d0000 00000000 00006364 76bb90bc
5fe0: 76bb8ec0 76bb8eb0 0001939c 00131f30 60000010 00000003 00000000 00000000
Call trace: 
[<808899c0>] (io_buffer_select) from [<80892d3c>] (io_recvmsg+0x230/0x420 io_uring/net.c:988)
 r7:00000040 r6:00000000 r5:854a2a00 r4:8503a000
[<80892b0c>] (io_recvmsg) from [<80886df4>] (__io_issue_sqe io_uring/io_uring.c:1740 [inline])
[<80892b0c>] (io_recvmsg) from [<80886df4>] (io_issue_sqe+0x284/0x658 io_uring/io_uring.c:1759)
 r10:83b81800 r9:0000000a r8:81cf0b5c r7:80000001 r6:00000000 r5:81cf0bd4
 r4:8503a000
[<80886b70>] (io_issue_sqe) from [<808877a8>] (io_queue_sqe io_uring/io_uring.c:1975 [inline])
[<80886b70>] (io_issue_sqe) from [<808877a8>] (io_submit_sqe io_uring/io_uring.c:2231 [inline])
[<80886b70>] (io_issue_sqe) from [<808877a8>] (io_submit_sqes+0x20c/0x938 io_uring/io_uring.c:2348)
 r10:83b81800 r9:00000000 r8:00000000 r7:84674000 r6:8503a000 r5:8503a06c
 r4:85443000
[<8088759c>] (io_submit_sqes) from [<80888250>] (__do_sys_io_uring_enter io_uring/io_uring.c:3408 [inline])
[<8088759c>] (io_submit_sqes) from [<80888250>] (sys_io_uring_enter+0x138/0x780 io_uring/io_uring.c:3342)
 r10:00000000 r9:83b81800 r8:00000000 r7:84996b40 r6:000027e2 r5:85443000
 r4:00000000
[<80888118>] (sys_io_uring_enter) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67)
Exception stack(0xdfbd5fa8 to 0xdfbd5ff0)
5fa0:                   00000000 00000000 00000003 000027e2 00000000 00000000
5fc0: 00000000 00000000 002e630c 000001aa 002d0000 00000000 00006364 76bb90bc
5fe0: 76bb8ec0 76bb8eb0 0001939c 00131f30
 r10:000001aa r9:83b81800 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