================================================================== BUG: KASAN: use-after-free in walk_stackframe+0x11c/0x260 arch/riscv/kernel/stacktrace.c:57 Read of size 8 at addr ffffaf802034be60 by task syz-executor.1/2921 CPU: 0 PID: 2921 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 [] kasan_save_stack+0x2c/0x58 mm/kasan/common.c:38 Allocated by task 11: (stack is not available) Last potentially related work creation: ------------[ cut here ]------------ slab index 432092 out of bounds (337) for stack id 040697dc WARNING: CPU: 0 PID: 2921 at lib/stackdepot.c:304 stack_depot_fetch lib/stackdepot.c:304 [inline] WARNING: CPU: 0 PID: 2921 at lib/stackdepot.c:304 stack_depot_print+0x66/0x70 lib/stackdepot.c:276 Modules linked in: CPU: 0 PID: 2921 Comm: syz-executor.1 Not tainted 5.17.0-rc1-syzkaller-00002-g0966d385830d #0 Hardware name: riscv-virtio,qemu (DT) epc : stack_depot_fetch lib/stackdepot.c:304 [inline] epc : stack_depot_print+0x66/0x70 lib/stackdepot.c:276 ra : stack_depot_fetch lib/stackdepot.c:304 [inline] ra : stack_depot_print+0x66/0x70 lib/stackdepot.c:276 epc : ffffffff80c00b8a ra : ffffffff80c00b8a sp : ffffaf802034bd20 gp : ffffffff85863ac0 tp : ffffaf800ce0c8c0 t0 : ffffffff86bcb657 t1 : fffff5ef0b53910c t2 : 0000000000000000 s0 : ffffaf802034bd30 s1 : ffffaf807af57d18 a0 : 000000000000003b a1 : 00000000000f0000 a2 : 0000000000000505 a3 : ffffffff8012252a a4 : 776248205322e400 a5 : 776248205322e400 a6 : 0000000000f00000 a7 : ffffaf805a9c8863 s2 : ffffaf802034be60 s3 : ffffaf80072e9000 s4 : ffffaf802034be00 s5 : ffffaf802034bea8 s6 : 0000000000003fff s7 : ffffaf802034be00 s8 : 0000000000400000 s9 : ffffffffffffc000 s10: ffffaf802034bee0 s11: 0000000000000008 t3 : fffffffff3f3f300 t4 : fffff5ef0b53910c t5 : fffff5ef0b53910d t6 : ffffaf802034b818 status: 0000000000000100 badaddr: 0000000000000000 cause: 0000000000000003 [] describe_object_stacks mm/kasan/report.c:216 [inline] [] describe_object mm/kasan/report.c:231 [inline] [] print_address_description.constprop.0+0x2fc/0x330 mm/kasan/report.c:263 [] __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 [] kasan_save_stack+0x2c/0x58 mm/kasan/common.c:38 irq event stamp: 3861 hardirqs last enabled at (3860): [] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline] hardirqs last enabled at (3860): [] _raw_spin_unlock_irqrestore+0x68/0x98 kernel/locking/spinlock.c:194 hardirqs last disabled at (3861): [] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline] hardirqs last disabled at (3861): [] _raw_spin_lock_irqsave+0x60/0x62 kernel/locking/spinlock.c:162 softirqs last enabled at (3768): [] softirq_handle_end kernel/softirq.c:401 [inline] softirqs last enabled at (3768): [] __do_softirq+0x618/0x8fc kernel/softirq.c:587 softirqs last disabled at (3817): [] do_softirq_own_stack include/asm-generic/softirq_stack.h:10 [inline] softirqs last disabled at (3817): [] invoke_softirq kernel/softirq.c:439 [inline] softirqs last disabled at (3817): [] __irq_exit_rcu+0x142/0x1f8 kernel/softirq.c:637 ---[ end trace 0000000000000000 ]--- Second to last potentially related work creation: ------------[ cut here ]------------ slab index 2094576 out of bounds (337) for stack id 1ffff5f0 WARNING: CPU: 0 PID: 2921 at lib/stackdepot.c:304 stack_depot_fetch lib/stackdepot.c:304 [inline] WARNING: CPU: 0 PID: 2921 at lib/stackdepot.c:304 stack_depot_print+0x66/0x70 lib/stackdepot.c:276 Modules linked in: CPU: 0 PID: 2921 Comm: syz-executor.1 Tainted: G W 5.17.0-rc1-syzkaller-00002-g0966d385830d #0 Hardware name: riscv-virtio,qemu (DT) epc : stack_depot_fetch lib/stackdepot.c:304 [inline] epc : stack_depot_print+0x66/0x70 lib/stackdepot.c:276 ra : stack_depot_fetch lib/stackdepot.c:304 [inline] ra : stack_depot_print+0x66/0x70 lib/stackdepot.c:276 epc : ffffffff80c00b8a ra : ffffffff80c00b8a sp : ffffaf802034bd20 gp : ffffffff85863ac0 tp : ffffaf800ce0c8c0 t0 : ffffffff86bcb657 t1 : fffff5ef0b53910c t2 : 0000000000000000 s0 : ffffaf802034bd30 s1 : ffffaf807af57d18 a0 : 000000000000003c a1 : 00000000000f0000 a2 : 0000000000000505 a3 : ffffffff8012252a a4 : 776248205322e400 a5 : 776248205322e400 a6 : 0000000000f00000 a7 : ffffaf805a9c8863 s2 : ffffaf802034be60 s3 : ffffaf80072e9000 s4 : ffffaf802034be00 s5 : ffffaf802034bea8 s6 : 0000000000003fff s7 : ffffaf802034be00 s8 : 0000000000400000 s9 : ffffffffffffc000 s10: ffffaf802034bee0 s11: 0000000000000008 t3 : fffffffff3f3f300 t4 : fffff5ef0b53910c t5 : fffff5ef0b53910d t6 : ffffaf802034b818 status: 0000000000000100 badaddr: 0000000000000000 cause: 0000000000000003 [] describe_object_stacks mm/kasan/report.c:221 [inline] [] describe_object mm/kasan/report.c:231 [inline] [] print_address_description.constprop.0+0x2ae/0x330 mm/kasan/report.c:263 [] __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 [] kasan_save_stack+0x2c/0x58 mm/kasan/common.c:38 irq event stamp: 3861 hardirqs last enabled at (3860): [] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline] hardirqs last enabled at (3860): [] _raw_spin_unlock_irqrestore+0x68/0x98 kernel/locking/spinlock.c:194 hardirqs last disabled at (3861): [] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline] hardirqs last disabled at (3861): [] _raw_spin_lock_irqsave+0x60/0x62 kernel/locking/spinlock.c:162 softirqs last enabled at (3768): [] softirq_handle_end kernel/softirq.c:401 [inline] softirqs last enabled at (3768): [] __do_softirq+0x618/0x8fc kernel/softirq.c:587 softirqs last disabled at (3817): [] do_softirq_own_stack include/asm-generic/softirq_stack.h:10 [inline] softirqs last disabled at (3817): [] invoke_softirq kernel/softirq.c:439 [inline] softirqs last disabled at (3817): [] __irq_exit_rcu+0x142/0x1f8 kernel/softirq.c:637 ---[ end trace 0000000000000000 ]--- The buggy address belongs to the object at ffffaf802034be00 which belongs to the cache fs_cache of size 168 The buggy address is located 96 bytes inside of 168-byte region [ffffaf802034be00, ffffaf802034bea8) The buggy address belongs to the page: page:ffffaf807af57d18 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffffaf802034b400 pfn:0xa054b flags: 0xa000000200(slab|section=20|node=0|zone=0) raw: 000000a000000200 ffffaf807aace2b0 0000000000000007 ffffaf80072e9000 raw: ffffaf802034b400 0000000080100000 00000001ffffffff 0000000000000000 raw: 00000000000007ff page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 2061, ts 933194771600, free_ts 933074337100 __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 alloc_slab_page.constprop.0+0xc2/0xfa mm/slub.c:1799 allocate_slab mm/slub.c:1944 [inline] new_slab+0x76/0x2cc mm/slub.c:2004 ___slab_alloc+0x56e/0x918 mm/slub.c:3018 __slab_alloc.constprop.0+0x50/0x8c mm/slub.c:3105 slab_alloc_node mm/slub.c:3196 [inline] slab_alloc mm/slub.c:3238 [inline] kmem_cache_alloc+0x39c/0x3de mm/slub.c:3243 copy_fs_struct+0x3a/0x158 fs/fs_struct.c:114 copy_fs kernel/fork.c:1527 [inline] copy_process+0x2400/0x3c34 kernel/fork.c:2155 kernel_clone+0xee/0x920 kernel/fork.c:2555 kernel_thread+0xf8/0x130 kernel/fork.c:2607 call_usermodehelper_exec_work kernel/umh.c:174 [inline] call_usermodehelper_exec_work+0xc8/0x122 kernel/umh.c:160 process_one_work+0x654/0xffe kernel/workqueue.c:2307 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_list+0x148/0x7fe mm/page_alloc.c:3441 release_pages+0x3f0/0xad0 mm/swap.c:980 free_pages_and_swap_cache+0x74/0x86 mm/swap_state.c:320 tlb_batch_pages_flush mm/mmu_gather.c:50 [inline] tlb_flush_mmu_free mm/mmu_gather.c:243 [inline] tlb_flush_mmu mm/mmu_gather.c:250 [inline] tlb_finish_mmu+0xe8/0x29a mm/mmu_gather.c:341 exit_mmap+0x170/0x412 mm/mmap.c:3180 __mmput kernel/fork.c:1114 [inline] mmput+0xee/0x2c2 kernel/fork.c:1135 exit_mm kernel/exit.c:507 [inline] do_exit+0x6f2/0x18fc kernel/exit.c:793 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: ffffaf802034bd00: 00 00 00 00 00 00 00 00 00 00 00 00 fb fb fb fb ffffaf802034bd80: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc >ffffaf802034be00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffffaf802034be80: fb fb fb fb fb fc fc fc f1 f1 f1 f1 00 00 00 f3 ffffaf802034bf00: f3 f3 f3 f3 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================