syzbot

usercopy: Kernel memory overwrite attempt detected to SLUB object 'task_struct' (offset 80, size 116)!
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kernel BUG at mm/usercopy.c:102!
Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM
Modules linked in:
CPU: 1 PID: 3010 Comm: syz-executor574 Not tainted 6.10.0-rc5-syzkaller #0
Hardware name: ARM-Versatile Express
PC is at usercopy_abort+0x98/0x9c mm/usercopy.c:102
LR is at __wake_up_klogd.part.0+0x7c/0xac kernel/printk/printk.c:3953
pc : [<818db348>]    lr : [<802bc47c>]    psr: 60000013
sp : df985d90  ip : df985cd8  fp : df985db4
r10: 81a00568  r9 : 00000078  r8 : 83dc1850
r7 : dde83f00  r6 : 00000000  r5 : 00000074  r4 : 00000050
r3 : 8416d400  r2 : 00000000  r1 : 00000000  r0 : 00000066
Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
Control: 30c5387d  Table: 843ce280  DAC: 00000000
Register r0 information: non-paged memory
Register r1 information: NULL pointer
Register r2 information: NULL pointer
Register r3 information: slab task_struct start 8416d400 pointer offset 0 size 3072
Register r4 information: non-paged memory
Register r5 information: non-paged memory
Register r6 information: NULL pointer
Register r7 information: non-slab/vmalloc memory
Register r8 information: slab task_struct start 83dc1800 pointer offset 80 size 3072
Register r9 information: non-paged memory
Register r10 information: non-slab/vmalloc memory
Register r11 information: 2-page vmalloc region starting at 0xdf984000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2797
Register r12 information: 2-page vmalloc region starting at 0xdf984000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2797
Process syz-executor574 (pid: 3010, stack limit = 0xdf984000)
Stack: (0xdf985d90 to 0xdf986000)
5d80:                                     81fff420 81fd1ad8 81fe61b8 00000050
5da0: 00000074 00000078 df985de4 df985db8 804c0c00 818db2bc 00000074 df985dc8
5dc0: 802161c0 83dc1850 00000074 00000000 83dc18c4 dde83f00 df985e1c df985de8
5de0: 804f91e4 804c0b34 00000074 20000084 df985e0c 83dc1850 00000074 20000084
5e00: 00000074 81a005a0 00000078 81a00568 df985e4c df985e20 80209d80 804f8f5c
5e20: 804e3ba8 818f3e08 df985e54 df985e38 80480f00 80209cf0 83dc1800 20000084
5e40: df985ef4 df985e50 8025455c 80209cfc 00000000 20000000 20000000 81a0057c
5e60: 818ff8e0 00000000 df985eb4 df985e78 8020d074 8020bfec 8020c004 00000000
5e80: 80280128 00000000 00000000 00000000 00000000 00000000 00000000 00000000
5ea0: 00000000 8416d400 df985edc df985eb8 8027e6bc 802ae26c 80282830 00000000
5ec0: 00000000 4c35cf55 83dc1800 20000080 00004202 00000002 00000000 20000080
5ee0: 8416d400 0000001a df985f6c df985ef8 8020a1b4 80254254 83dc1800 83dc2084
5f00: df985f1c df985f10 818ffd8c 8027ccbc df985f6c df985f20 80282990 818ffd68
5f20: df985f54 00000000 8027e6bc 60000013 818ad610 818c48c4 df985f54 4c35cf55
5f40: 83dc1800 00004205 83dc1800 4c35cf55 00004205 83dc1800 00000002 00000000
5f60: df985fa4 df985f70 80253f00 8020a110 80216088 4c35cf55 00000000 00000000
5f80: 00000000 0008e050 0000001a 8020029c 8416d400 0000001a 00000000 df985fa8
5fa0: 80200060 80253cd4 00000000 00000000 00004205 00000bc3 00000002 20000080
5fc0: 00000000 00000000 0008e050 0000001a 00000000 7e941c84 00002710 00000000
5fe0: 7e941c70 7e941c60 00010650 0002e7a0 00000010 00004205 00000000 00000000
Call trace: 
[<818db2b0>] (usercopy_abort) from [<804c0c00>] (__check_heap_object+0xd8/0xf4 mm/slub.c:5533)
[<804c0b28>] (__check_heap_object) from [<804f91e4>] (check_heap_object mm/usercopy.c:196 [inline])
[<804c0b28>] (__check_heap_object) from [<804f91e4>] (__check_object_size mm/usercopy.c:251 [inline])
[<804c0b28>] (__check_heap_object) from [<804f91e4>] (__check_object_size+0x294/0x310 mm/usercopy.c:213)
 r8:dde83f00 r7:83dc18c4 r6:00000000 r5:00000074 r4:83dc1850
[<804f8f50>] (__check_object_size) from [<80209d80>] (check_object_size include/linux/thread_info.h:215 [inline])
[<804f8f50>] (__check_object_size) from [<80209d80>] (__copy_from_user include/linux/uaccess.h:101 [inline])
[<804f8f50>] (__check_object_size) from [<80209d80>] (user_regset_copyin include/linux/regset.h:268 [inline])
[<804f8f50>] (__check_object_size) from [<80209d80>] (fpa_set+0x90/0x118 arch/arm/kernel/ptrace.c:587)
 r10:81a00568 r9:00000078 r8:81a005a0 r7:00000074 r6:20000084 r5:00000074
 r4:83dc1850
[<80209cf0>] (fpa_set) from [<8025455c>] (copy_regset_from_user include/linux/regset.h:337 [inline])
[<80209cf0>] (fpa_set) from [<8025455c>] (ptrace_regset kernel/ptrace.c:906 [inline])
[<80209cf0>] (fpa_set) from [<8025455c>] (ptrace_request+0x314/0xa70 kernel/ptrace.c:1218)
 r6:20000084 r5:83dc1800 r4:80209cf0
[<80254248>] (ptrace_request) from [<8020a1b4>] (arch_ptrace+0xb0/0x424 arch/arm/kernel/ptrace.c:818)
 r10:0000001a r9:8416d400 r8:20000080 r7:00000000 r6:00000002 r5:00004202
 r4:20000080
[<8020a104>] (arch_ptrace) from [<80253f00>] (__do_sys_ptrace kernel/ptrace.c:1285 [inline])
[<8020a104>] (arch_ptrace) from [<80253f00>] (sys_ptrace+0x238/0x4e0 kernel/ptrace.c:1258)
 r7:00000000 r6:00000002 r5:83dc1800 r4:00004205
[<80253cc8>] (sys_ptrace) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67)
Exception stack(0xdf985fa8 to 0xdf985ff0)
5fa0:                   00000000 00000000 00004205 00000bc3 00000002 20000080
5fc0: 00000000 00000000 0008e050 0000001a 00000000 7e941c84 00002710 00000000
5fe0: 7e941c70 7e941c60 00010650 0002e7a0
 r10:0000001a r9:8416d400 r8:8020029c r7:0000001a r6:0008e050 r5:00000000
 r4:00000000
Code: e30f0424 e34801ff e58dc000 ebfff359 (e7f001f2) 
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	e30f0424 	movw	r0, #62500	@ 0xf424
   4:	e34801ff 	movt	r0, #33279	@ 0x81ff
   8:	e58dc000 	str	ip, [sp]
   c:	ebfff359 	bl	0xffffcd78
* 10:	e7f001f2 	udf	#18 <-- trapping instruction