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 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