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: 1 UID: 0 PID: 12302 Comm: syz.5.1564 Not tainted 6.12.0-rc7-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:4495 pc : [<819a3a88>] lr : [<802bcae4>] psr: 60000013 sp : dff9dd90 ip : dff9dcd0 fp : dff9ddb4 r10: 81a0056c r9 : 00000078 r8 : 8590ec50 r7 : ddec1520 r6 : 00000000 r5 : 00000074 r4 : 00000050 r3 : 85e33000 r2 : 00000000 r1 : 00000000 r0 : 00000066 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 85052a40 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 85e33000 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 8590ec00 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 0xdff9c000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2786 Register r12 information: 2-page vmalloc region starting at 0xdff9c000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2786 Process syz.5.1564 (pid: 12302, stack limit = 0xdff9c000) Stack: (0xdff9dd90 to 0xdff9e000) dd80: 8205c038 8202da2c 8204307c 00000050 dda0: 00000074 00000078 dff9dde4 dff9ddb8 804cf9b8 819a39fc 00000074 dff9ddc8 ddc0: 802147c0 8590ec50 00000074 00000000 8590ecc4 ddec1520 dff9de1c dff9dde8 dde0: 8050e86c 804cf8ec 00000074 20000084 dff9de0c 8590ec50 00000074 20000084 de00: 00000074 81a005a4 00000078 81a0056c dff9de4c dff9de20 80209d94 8050e5f0 de20: 8260ca7c 82eea040 00000064 dff9de2c dff9de2c 80209d04 8590ec00 20000084 de40: dff9def4 dff9de50 80252f10 80209d10 00000000 20000000 20000000 81a00580 de60: 819c89bc 00000000 dff9deb4 dff9de78 8020d090 8020c014 824bc400 00000000 de80: 8027ebe4 00000000 00000000 00000000 00000000 00000000 00000000 00000000 dea0: 00000000 85e33000 dff9dedc dff9deb8 8027d414 802ae61c 00000000 00000000 dec0: dff9deec 283987f8 8590ec00 20000080 00004202 00000002 00000000 20000080 dee0: 85e33000 0000001a dff9df6c dff9def8 8020a1c4 80252c08 8590ec00 8590f484 df00: dff9df1c dff9df10 819c8e68 8027b990 dff9df6c dff9df20 802805a4 819c8e44 df20: dff9df54 00000000 8027d414 60000013 81975950 8198cbd4 dff9df54 283987f8 df40: 8590ec00 00004205 8590ec00 283987f8 00004205 8590ec00 00000002 00000000 df60: dff9dfa4 dff9df70 802528b4 8020a120 80202cc0 283987f8 dff9dfac 00000000 df80: 00000000 002862f4 0000001a 8020029c 85e33000 0000001a 00000000 dff9dfa8 dfa0: 80200060 80252688 00000000 00000000 00004205 00000495 00000002 20000080 dfc0: 00000000 00000000 002862f4 0000001a 00000000 00006364 003d0f00 76bcb0bc dfe0: 76bcaec0 76bcaeb0 00018af0 00133450 60000010 00004205 00000000 00000000 Call trace: [<819a39f0>] (usercopy_abort) from [<804cf9b8>] (__check_heap_object+0xd8/0xf4 mm/slub.c:5651) [<804cf8e0>] (__check_heap_object) from [<8050e86c>] (check_heap_object mm/usercopy.c:196 [inline]) [<804cf8e0>] (__check_heap_object) from [<8050e86c>] (__check_object_size mm/usercopy.c:251 [inline]) [<804cf8e0>] (__check_heap_object) from [<8050e86c>] (__check_object_size+0x288/0x304 mm/usercopy.c:213) r8:ddec1520 r7:8590ecc4 r6:00000000 r5:00000074 r4:8590ec50 [<8050e5e4>] (__check_object_size) from [<80209d94>] (check_object_size include/linux/thread_info.h:215 [inline]) [<8050e5e4>] (__check_object_size) from [<80209d94>] (__copy_from_user include/linux/uaccess.h:110 [inline]) [<8050e5e4>] (__check_object_size) from [<80209d94>] (user_regset_copyin include/linux/regset.h:268 [inline]) [<8050e5e4>] (__check_object_size) from [<80209d94>] (fpa_set+0x90/0x118 arch/arm/kernel/ptrace.c:587) r10:81a0056c r9:00000078 r8:81a005a4 r7:00000074 r6:20000084 r5:00000074 r4:8590ec50 [<80209d04>] (fpa_set) from [<80252f10>] (copy_regset_from_user include/linux/regset.h:337 [inline]) [<80209d04>] (fpa_set) from [<80252f10>] (ptrace_regset kernel/ptrace.c:906 [inline]) [<80209d04>] (fpa_set) from [<80252f10>] (ptrace_request+0x314/0xa78 kernel/ptrace.c:1218) r6:20000084 r5:8590ec00 r4:80209d04 [<80252bfc>] (ptrace_request) from [<8020a1c4>] (arch_ptrace+0xb0/0x424 arch/arm/kernel/ptrace.c:818) r10:0000001a r9:85e33000 r8:20000080 r7:00000000 r6:00000002 r5:00004202 r4:20000080 [<8020a114>] (arch_ptrace) from [<802528b4>] (__do_sys_ptrace kernel/ptrace.c:1285 [inline]) [<8020a114>] (arch_ptrace) from [<802528b4>] (sys_ptrace+0x238/0x4e0 kernel/ptrace.c:1258) r7:00000000 r6:00000002 r5:8590ec00 r4:00004205 [<8025267c>] (sys_ptrace) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdff9dfa8 to 0xdff9dff0) dfa0: 00000000 00000000 00004205 00000495 00000002 20000080 dfc0: 00000000 00000000 002862f4 0000001a 00000000 00006364 003d0f00 76bcb0bc dfe0: 76bcaec0 76bcaeb0 00018af0 00133450 r10:0000001a r9:85e33000 r8:8020029c r7:0000001a r6:002862f4 r5:00000000 r4:00000000 Code: e30c003c e3480205 e58dc000 ebfff273 (e7f001f2) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: e30c003c movw r0, #49212 @ 0xc03c 4: e3480205 movt r0, #33285 @ 0x8205 8: e58dc000 str ip, [sp] c: ebfff273 bl 0xffffc9e0 * 10: e7f001f2 udf #18 <-- trapping instruction