usercopy: Kernel memory overwrite attempt detected to SLUB object 'task_struct' (offset 80, size 116)! ------------[ cut here ]------------ kernel BUG at mm/usercopy.c:102! Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM Modules linked in: CPU: 0 UID: 0 PID: 13192 Comm: syz.1.515 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:4496 pc : [<819ae208>] lr : [<802bd9c4>] psr: 60000013 sp : dfdb5d90 ip : dfdb5cd0 fp : dfdb5db4 r10: 81a00568 r9 : 00000078 r8 : 84374850 r7 : dde90bc0 r6 : 00000000 r5 : 00000074 r4 : 00000050 r3 : 851a5400 r2 : 00000000 r1 : 00000000 r0 : 00000066 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 84fcd700 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 851a5400 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 84374800 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 0xdfdb4000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2787 Register r12 information: 2-page vmalloc region starting at 0xdfdb4000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2787 Process syz.1.515 (pid: 13192, stack limit = 0xdfdb4000) Stack: (0xdfdb5d90 to 0xdfdb6000) 5d80: 8205dadc 8202f5a0 820449b4 00000050 5da0: 00000074 00000078 dfdb5de4 dfdb5db8 804d1bc8 819ae17c 00000074 dfdb5dc8 5dc0: 802147a0 84374850 00000074 00000000 843748c4 dde90bc0 dfdb5e1c dfdb5de8 5de0: 80510994 804d1afc 00000074 20000084 dfdb5e0c 84374850 00000074 20000084 5e00: 00000074 81a005a0 00000078 81a00568 dfdb5e4c dfdb5e20 80209d90 80510718 5e20: dfdb5e64 82e54f80 00000064 dfdb5e2c dfdb5e2c 80209d00 84374800 20000084 5e40: dfdb5ef4 dfdb5e50 802534f4 80209d0c 00000000 20000000 20000000 81a0057c 5e60: 819d2eec 00000000 dfdb5eb4 dfdb5e78 8020d0ac 8020c014 824bc340 00000000 5e80: 8027f8a0 00000000 00000000 00000000 00000000 00000000 00000000 00000000 5ea0: 00000000 851a5400 dfdb5edc dfdb5eb8 8027e1e4 802af444 00000000 00000000 5ec0: dfdb5eec 32e8b41f 84374800 20000080 00004202 00000002 00000000 20000080 5ee0: 851a5400 0000001a dfdb5f6c dfdb5ef8 8020a1c0 802531ec 84374800 84375084 5f00: dfdb5f1c dfdb5f10 819d3398 8027c5a8 dfdb5f6c dfdb5f20 8028127c 819d3374 5f20: dfdb5f54 00000000 8027e1e4 60000013 819800d0 81997354 dfdb5f54 32e8b41f 5f40: 00004205 84374800 00004205 32e8b41f 84374800 00004205 00000002 00000000 5f60: dfdb5fa4 dfdb5f70 80252e9c 8020a11c 80202cc0 32e8b41f dfdb5fac 00000000 5f80: 00000000 002862f4 0000001a 8020029c 851a5400 0000001a 00000000 dfdb5fa8 5fa0: 80200060 80252c70 00000000 00000000 00004205 000003b2 00000002 20000080 5fc0: 00000000 00000000 002862f4 0000001a 00000000 00006364 003d0f00 76b290bc 5fe0: 76b28ec0 76b28eb0 00018af0 00133450 60000010 00004205 00000000 00000000 Call trace: [<819ae170>] (usercopy_abort) from [<804d1bc8>] (__check_heap_object+0xd8/0xf4 mm/slub.c:5651) [<804d1af0>] (__check_heap_object) from [<80510994>] (check_heap_object mm/usercopy.c:196 [inline]) [<804d1af0>] (__check_heap_object) from [<80510994>] (__check_object_size mm/usercopy.c:251 [inline]) [<804d1af0>] (__check_heap_object) from [<80510994>] (__check_object_size+0x288/0x304 mm/usercopy.c:213) r8:dde90bc0 r7:843748c4 r6:00000000 r5:00000074 r4:84374850 [<8051070c>] (__check_object_size) from [<80209d90>] (check_object_size include/linux/thread_info.h:228 [inline]) [<8051070c>] (__check_object_size) from [<80209d90>] (__copy_from_user include/linux/uaccess.h:110 [inline]) [<8051070c>] (__check_object_size) from [<80209d90>] (user_regset_copyin include/linux/regset.h:268 [inline]) [<8051070c>] (__check_object_size) from [<80209d90>] (fpa_set+0x90/0x118 arch/arm/kernel/ptrace.c:587) r10:81a00568 r9:00000078 r8:81a005a0 r7:00000074 r6:20000084 r5:00000074 r4:84374850 [<80209d00>] (fpa_set) from [<802534f4>] (copy_regset_from_user include/linux/regset.h:337 [inline]) [<80209d00>] (fpa_set) from [<802534f4>] (ptrace_regset kernel/ptrace.c:906 [inline]) [<80209d00>] (fpa_set) from [<802534f4>] (ptrace_request+0x314/0xa78 kernel/ptrace.c:1218) r6:20000084 r5:84374800 r4:80209d00 [<802531e0>] (ptrace_request) from [<8020a1c0>] (arch_ptrace+0xb0/0x424 arch/arm/kernel/ptrace.c:818) r10:0000001a r9:851a5400 r8:20000080 r7:00000000 r6:00000002 r5:00004202 r4:20000080 [<8020a110>] (arch_ptrace) from [<80252e9c>] (__do_sys_ptrace kernel/ptrace.c:1285 [inline]) [<8020a110>] (arch_ptrace) from [<80252e9c>] (sys_ptrace+0x238/0x4dc kernel/ptrace.c:1258) r7:00000000 r6:00000002 r5:00004205 r4:84374800 [<80252c64>] (sys_ptrace) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfdb5fa8 to 0xdfdb5ff0) 5fa0: 00000000 00000000 00004205 000003b2 00000002 20000080 5fc0: 00000000 00000000 002862f4 0000001a 00000000 00006364 003d0f00 76b290bc 5fe0: 76b28ec0 76b28eb0 00018af0 00133450 r10:0000001a r9:851a5400 r8:8020029c r7:0000001a r6:002862f4 r5:00000000 r4:00000000 Code: e30d0ae0 e3480205 e58dc000 ebfff273 (e7f001f2) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: e30d0ae0 movw r0, #56032 @ 0xdae0 4: e3480205 movt r0, #33285 @ 0x8205 8: e58dc000 str ip, [sp] c: ebfff273 bl 0xffffc9e0 * 10: e7f001f2 udf #18 <-- trapping instruction