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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: 0 PID: 3083 Comm: syz-executor190 Not tainted 6.6.0-rc6-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:3868
pc : [<818257cc>]    lr : [<802b69ac>]    psr: 60000013
sp : dfa59e48  ip : dfa59d90  fp : dfa59e6c
r10: 0000001a  r9 : 84531780  r8 : 84532390
r7 : dde94ac0  r6 : 00000000  r5 : 00000074  r4 : 00000050
r3 : 84531780  r2 : 00000000  r1 : 00000000  r0 : 00000066
Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
Control: 30c5387d  Table: 8442c2c0  DAC: fffffffd
Register r0 information: non-paged memory
Register r1 information: NULL pointer
Register r2 information: NULL pointer
Register r3 information: slab task_struct start 84531780 pointer offset 0 size 3008
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 84532340 pointer offset 80 size 3008
Register r9 information: slab task_struct start 84531780 pointer offset 0 size 3008
Register r10 information: non-paged memory
Register r11 information: 2-page vmalloc region starting at 0xdfa58000 allocated at kernel_clone+0xac/0x424 kernel/fork.c:2909
Register r12 information: 2-page vmalloc region starting at 0xdfa58000 allocated at kernel_clone+0xac/0x424 kernel/fork.c:2909
Process syz-executor190 (pid: 3083, stack limit = 0xdfa58000)
Stack: (0xdfa59e48 to 0xdfa5a000)
9e40:                   81fd069c 81fa5b28 81fba240 00000050 00000074 84531780
9e60: dfa59e9c dfa59e70 804b2fd8 81825740 00000074 dfa59e80 802162b4 84532390
9e80: 00000074 00000000 84532404 dde94ac0 dfa59ed4 dfa59ea0 804d1e68 804b2f0c
9ea0: 00000074 00000000 dfa59ec4 84532390 00000074 00000000 00000000 00000000
9ec0: 84531780 0000001a dfa59efc dfa59ed8 80209f08 804d1c88 84532340 ddde5640
9ee0: dfa59f04 dfa59ef0 00000000 0000000c dfa59f74 dfa59f00 8020a544 80209e84
9f00: 00000000 00000000 84532340 00008008 dfa59f2c dfa59f20 81849880 80278ea8
9f20: dfa59f74 dfa59f30 8027ea10 8184985c 8027a84c 60000013 817f951c 8180ecb4
9f40: dfa59f5c 4f4e6812 0000000f 84532340 0000000f 4f4e6812 84532340 0000000f
9f60: 00000000 00000000 dfa59fa4 dfa59f78 802528c0 8020a25c 00000000 4f4e6812
9f80: 00000000 00000000 0008e050 0000001a 80200288 84531780 00000000 dfa59fa8
9fa0: 80200060 80252690 00000000 00000000 0000000f 00000c0c 00000000 00000000
9fc0: 00000000 00000000 0008e050 0000001a 000f4240 00000000 7ef9bc84 00003a97
9fe0: 7ef9bc70 7ef9bc60 00010638 0002e780 00000010 0000000f 00000000 00000000
Backtrace: 
[<81825734>] (usercopy_abort) from [<804b2fd8>] (__check_heap_object+0xd8/0xf4 mm/slub.c:4784)
[<804b2f00>] (__check_heap_object) from [<804d1e68>] (check_heap_object mm/usercopy.c:196 [inline])
[<804b2f00>] (__check_heap_object) from [<804d1e68>] (__check_object_size mm/usercopy.c:251 [inline])
[<804b2f00>] (__check_heap_object) from [<804d1e68>] (__check_object_size+0x1ec/0x30c mm/usercopy.c:213)
 r8:dde94ac0 r7:84532404 r6:00000000 r5:00000074 r4:84532390
[<804d1c7c>] (__check_object_size) from [<80209f08>] (check_object_size include/linux/thread_info.h:215 [inline])
[<804d1c7c>] (__check_object_size) from [<80209f08>] (__copy_from_user include/linux/uaccess.h:101 [inline])
[<804d1c7c>] (__check_object_size) from [<80209f08>] (user_regset_copyin include/linux/regset.h:268 [inline])
[<804d1c7c>] (__check_object_size) from [<80209f08>] (fpa_set+0x90/0xfc arch/arm/kernel/ptrace.c:587)
 r10:0000001a r9:84531780 r8:00000000 r7:00000000 r6:00000000 r5:00000074
 r4:84532390
[<80209e78>] (fpa_set) from [<8020a544>] (copy_regset_from_user include/linux/regset.h:337 [inline])
[<80209e78>] (fpa_set) from [<8020a544>] (arch_ptrace+0x2f4/0x3e4 arch/arm/kernel/ptrace.c:762)
 r5:0000000c r4:00000000
[<8020a250>] (arch_ptrace) from [<802528c0>] (__do_sys_ptrace kernel/ptrace.c:1305 [inline])
[<8020a250>] (arch_ptrace) from [<802528c0>] (sys_ptrace+0x23c/0x4c0 kernel/ptrace.c:1278)
 r7:00000000 r6:00000000 r5:0000000f r4:84532340
[<80252684>] (sys_ptrace) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:66)
Exception stack(0xdfa59fa8 to 0xdfa59ff0)
9fa0:                   00000000 00000000 0000000f 00000c0c 00000000 00000000
9fc0: 00000000 00000000 0008e050 0000001a 000f4240 00000000 7ef9bc84 00003a97
9fe0: 7ef9bc70 7ef9bc60 00010638 0002e780
 r9:84531780 r8:80200288 r7:0000001a r6:0008e050 r5:00000000 r4:00000000
Code: e30006a0 e34801fd e58dc000 ebfff341 (e7f001f2) 
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	e30006a0 	movw	r0, #1696	@ 0x6a0
   4:	e34801fd 	movt	r0, #33277	@ 0x81fd
   8:	e58dc000 	str	ip, [sp]
   c:	ebfff341 	bl	0xffffcd18
* 10:	e7f001f2 	udf	#18 <-- trapping instruction