================================================================== BUG: KASAN: use-after-free in walk_stackframe+0x11c/0x260 arch/riscv/kernel/stacktrace.c:57 Read of size 8 at addr ffffaf801f94bf50 by task syz-executor.1/2759 CPU: 0 PID: 2759 Comm: syz-executor.1 Not tainted 5.17.0-rc1-syzkaller-00002-g0966d385830d #0 Hardware name: riscv-virtio,qemu (DT) Call Trace: [] dump_backtrace+0x2e/0x3c arch/riscv/kernel/stacktrace.c:113 [] show_stack+0x34/0x40 arch/riscv/kernel/stacktrace.c:119 [] __dump_stack lib/dump_stack.c:88 [inline] [] dump_stack_lvl+0xe4/0x150 lib/dump_stack.c:106 [] print_address_description.constprop.0+0x2a/0x330 mm/kasan/report.c:255 [] __kasan_report mm/kasan/report.c:442 [inline] [] kasan_report+0x184/0x1e0 mm/kasan/report.c:459 [] check_region_inline mm/kasan/generic.c:183 [inline] [] __asan_load8+0x6e/0x96 mm/kasan/generic.c:256 [] walk_stackframe+0x11c/0x260 arch/riscv/kernel/stacktrace.c:57 [] arch_stack_walk+0x2c/0x3c arch/riscv/kernel/stacktrace.c:146 [] stack_trace_save+0xa6/0xd8 kernel/stacktrace.c:122 The buggy address belongs to the page: page:ffffaf807af2ad18 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x9fb4b flags: 0x9800000000(section=19|node=0|zone=0) raw: 0000009800000000 0000000000000100 0000000000000122 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 raw: 00000000000007ff page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 0, migratetype Unmovable, gfp_mask 0x2dc2(GFP_KERNEL|__GFP_HIGHMEM|__GFP_NOWARN|__GFP_ZERO), pid 2036, ts 579108433400, free_ts 726537993600 __set_page_owner+0x48/0x136 mm/page_owner.c:183 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0xd0/0x10a mm/page_alloc.c:2427 prep_new_page mm/page_alloc.c:2434 [inline] get_page_from_freelist+0x8da/0x12d8 mm/page_alloc.c:4165 __alloc_pages+0x150/0x3b6 mm/page_alloc.c:5389 alloc_pages+0x132/0x2a6 mm/mempolicy.c:2271 vm_area_alloc_pages mm/vmalloc.c:2902 [inline] __vmalloc_area_node mm/vmalloc.c:2962 [inline] __vmalloc_node_range+0x946/0xab2 mm/vmalloc.c:3107 vmalloc_user+0x76/0x8c mm/vmalloc.c:3243 kcov_mmap+0x2e/0x112 kernel/kcov.c:468 call_mmap include/linux/fs.h:2079 [inline] mmap_region+0x7a0/0xa88 mm/mmap.c:1793 do_mmap+0x784/0x8d2 mm/mmap.c:1582 vm_mmap_pgoff+0x1a2/0x24e mm/util.c:519 ksys_mmap_pgoff+0x288/0x2ea mm/mmap.c:1630 riscv_sys_mmap arch/riscv/kernel/sys_riscv.c:25 [inline] __do_sys_mmap arch/riscv/kernel/sys_riscv.c:34 [inline] sys_mmap+0x9e/0xc4 arch/riscv/kernel/sys_riscv.c:30 ret_from_syscall+0x0/0x2 page last free stack trace: __reset_page_owner+0x4a/0xea mm/page_owner.c:142 reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1352 [inline] free_pcp_prepare+0x29c/0x45e mm/page_alloc.c:1404 free_unref_page_prepare mm/page_alloc.c:3325 [inline] free_unref_page+0x6a/0x31e mm/page_alloc.c:3404 free_the_page mm/page_alloc.c:706 [inline] __free_pages+0xe2/0x112 mm/page_alloc.c:5474 __vunmap+0x67e/0x8c4 mm/vmalloc.c:2635 __vfree+0x70/0x104 mm/vmalloc.c:2683 vfree+0x9a/0xdc mm/vmalloc.c:2714 kcov_put kernel/kcov.c:411 [inline] kcov_put kernel/kcov.c:407 [inline] kcov_close+0x44/0x72 kernel/kcov.c:513 __fput+0x164/0x502 fs/file_table.c:311 ____fput+0x1a/0x24 fs/file_table.c:344 task_work_run+0xdc/0x154 kernel/task_work.c:164 exit_task_work include/linux/task_work.h:32 [inline] do_exit+0x7cc/0x18fc kernel/exit.c:806 do_group_exit+0x90/0x17e kernel/exit.c:935 __do_sys_exit_group kernel/exit.c:946 [inline] __wake_up_parent+0x0/0x4a kernel/exit.c:944 ret_from_syscall+0x0/0x2 Memory state around the buggy address: ffffaf801f94be00: 00 00 00 00 00 00 00 00 00 00 00 00 ff ff ff ff ffffaf801f94be80: 00 00 00 00 00 00 00 00 ff ff ff ff ff ff ff ff >ffffaf801f94bf00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffffaf801f94bf80: ff ff ff ff f1 f1 f1 f1 00 00 00 f3 f3 f3 f3 f3 ffffaf801f94c000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================