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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 UID: 0 PID: 4174 Comm: syz.0.116 Not tainted 6.12.0-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:4525
pc : [<819be580>]    lr : [<802be434>]    psr: 60000013
sp : dfb1dd90  ip : dfb1dcd0  fp : dfb1ddb4
r10: 81a00568  r9 : 00000078  r8 : 834b9850
r7 : dde6f9e0  r6 : 00000000  r5 : 00000074  r4 : 00000050
r3 : 834ba400  r2 : 00000000  r1 : 00000000  r0 : 00000066
Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
Control: 30c5387d  Table: 85078dc0  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 834ba400 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 834b9800 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 0xdfb1c000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2787
Register r12 information: 2-page vmalloc region starting at 0xdfb1c000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2787
Process syz.0.116 (pid: 4174, stack limit = 0xdfb1c000)
Stack: (0xdfb1dd90 to 0xdfb1e000)
dd80:                                     8205f678 82030fcc 820464dc 00000050
dda0: 00000074 00000078 dfb1dde4 dfb1ddb8 804d5d54 819be4f4 00000074 dfb1ddc8
ddc0: 80214800 834b9850 00000074 00000000 834b98c4 dde6f9e0 dfb1de1c dfb1dde8
dde0: 80514b34 804d5c88 00000074 20000084 dfb1de0c 834b9850 00000074 20000084
de00: 00000074 81a005a0 00000078 81a00568 dfb1de4c dfb1de20 80209db4 805148b8
de20: 00000000 82e52dc0 00000064 dfb1de2c dfb1de2c 80209d24 834b9800 20000084
de40: dfb1def4 dfb1de50 80253634 80209d30 00000000 20000000 20000000 81a0057c
de60: 819e3204 00000000 dfb1deb4 dfb1de78 8020d0cc 8020c034 dfb1de94 00000000
de80: 8027fa10 00000000 00000000 00000000 00000000 00000000 00000000 00000000
dea0: 00000000 834ba400 dfb1dedc dfb1deb8 8027e354 802af5ec 00000000 00000000
dec0: dfb1deec ca330578 834b9800 20000080 00004202 00000002 00000000 20000080
dee0: 834ba400 0000001a dfb1df6c dfb1def8 8020a1e4 8025332c 834b9800 834ba084
df00: dfb1df1c dfb1df10 819e36b0 8027c778 dfb1df6c dfb1df20 802813ec 819e368c
df20: dfb1df54 00000000 8027e354 60000013 81990410 819a7694 dfb1df54 ca330578
df40: 00004205 834b9800 00004205 ca330578 834b9800 00004205 00000002 00000000
df60: dfb1dfa4 dfb1df70 80252fdc 8020a140 80202cc0 ca330578 dfb1dfac 00000000
df80: 00000000 002862f4 0000001a 8020029c 834ba400 0000001a 00000000 dfb1dfa8
dfa0: 80200060 80252db0 00000000 00000000 00004205 000000ba 00000002 20000080
dfc0: 00000000 00000000 002862f4 0000001a 00000000 00006364 003d0f00 76b360bc
dfe0: 76b35ec0 76b35eb0 00018af0 00133450 60000010 00004205 00000000 00000000
Call trace: 
[<819be4e8>] (usercopy_abort) from [<804d5d54>] (__check_heap_object+0xd8/0xf4 mm/slub.c:5651)
[<804d5c7c>] (__check_heap_object) from [<80514b34>] (check_heap_object mm/usercopy.c:196 [inline])
[<804d5c7c>] (__check_heap_object) from [<80514b34>] (__check_object_size mm/usercopy.c:251 [inline])
[<804d5c7c>] (__check_heap_object) from [<80514b34>] (__check_object_size+0x288/0x304 mm/usercopy.c:213)
 r8:dde6f9e0 r7:834b98c4 r6:00000000 r5:00000074 r4:834b9850
[<805148ac>] (__check_object_size) from [<80209db4>] (check_object_size include/linux/thread_info.h:228 [inline])
[<805148ac>] (__check_object_size) from [<80209db4>] (__copy_from_user include/linux/uaccess.h:110 [inline])
[<805148ac>] (__check_object_size) from [<80209db4>] (user_regset_copyin include/linux/regset.h:268 [inline])
[<805148ac>] (__check_object_size) from [<80209db4>] (fpa_set+0x90/0x118 arch/arm/kernel/ptrace.c:587)
 r10:81a00568 r9:00000078 r8:81a005a0 r7:00000074 r6:20000084 r5:00000074
 r4:834b9850
[<80209d24>] (fpa_set) from [<80253634>] (copy_regset_from_user include/linux/regset.h:337 [inline])
[<80209d24>] (fpa_set) from [<80253634>] (ptrace_regset kernel/ptrace.c:906 [inline])
[<80209d24>] (fpa_set) from [<80253634>] (ptrace_request+0x314/0xa78 kernel/ptrace.c:1218)
 r6:20000084 r5:834b9800 r4:80209d24
[<80253320>] (ptrace_request) from [<8020a1e4>] (arch_ptrace+0xb0/0x424 arch/arm/kernel/ptrace.c:818)
 r10:0000001a r9:834ba400 r8:20000080 r7:00000000 r6:00000002 r5:00004202
 r4:20000080
[<8020a134>] (arch_ptrace) from [<80252fdc>] (__do_sys_ptrace kernel/ptrace.c:1285 [inline])
[<8020a134>] (arch_ptrace) from [<80252fdc>] (sys_ptrace+0x238/0x4dc kernel/ptrace.c:1258)
 r7:00000000 r6:00000002 r5:00004205 r4:834b9800
[<80252da4>] (sys_ptrace) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67)
Exception stack(0xdfb1dfa8 to 0xdfb1dff0)
dfa0:                   00000000 00000000 00004205 000000ba 00000002 20000080
dfc0: 00000000 00000000 002862f4 0000001a 00000000 00006364 003d0f00 76b360bc
dfe0: 76b35ec0 76b35eb0 00018af0 00133450
 r10:0000001a r9:834ba400 r8:8020029c r7:0000001a r6:002862f4 r5:00000000
 r4:00000000
Code: e30f067c e3480205 e58dc000 ebfff265 (e7f001f2) 
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	e30f067c 	movw	r0, #63100	@ 0xf67c
   4:	e3480205 	movt	r0, #33285	@ 0x8205
   8:	e58dc000 	str	ip, [sp]
   c:	ebfff265 	bl	0xffffc9a8
* 10:	e7f001f2 	udf	#18 <-- trapping instruction