================================================================== BUG: KASAN: use-after-free in walk_stackframe+0x11c/0x260 arch/riscv/kernel/stacktrace.c:57 Read of size 8 at addr ffffaf800f987fa0 by task syz-executor.0/2070 CPU: 0 PID: 2070 Comm: syz-executor.0 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:ffffaf807aaabdf8 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x8fb87 flags: 0x8800000000(section=17|node=0|zone=0) raw: 0000008800000000 0000000000000000 ffffaf807aaabe00 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 3, migratetype Unmovable, gfp_mask 0xd2a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1999, ts 337331160900, free_ts 1391132954100 __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] __kmalloc_node_track_caller+0x26c/0x362 mm/slub.c:4957 kmalloc_reserve net/core/skbuff.c:354 [inline] __alloc_skb+0xee/0x2e4 net/core/skbuff.c:426 __napi_alloc_skb+0x72/0x214 net/core/skbuff.c:568 napi_alloc_skb include/linux/skbuff.h:3005 [inline] page_to_skb+0x16e/0x70e drivers/net/virtio_net.c:437 receive_mergeable drivers/net/virtio_net.c:1039 [inline] receive_buf+0xa20/0x3e50 drivers/net/virtio_net.c:1149 virtnet_receive drivers/net/virtio_net.c:1441 [inline] virtnet_poll+0x39c/0x986 drivers/net/virtio_net.c:1550 __napi_poll+0x7c/0x358 net/core/dev.c:6365 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 __free_slab+0x122/0x27c mm/slub.c:2028 free_slab mm/slub.c:2043 [inline] discard_slab+0x4c/0x7a mm/slub.c:2049 __slab_free+0x20a/0x29c mm/slub.c:3414 do_slab_free mm/slub.c:3497 [inline] ___cache_free+0x17c/0x354 mm/slub.c:3516 qlink_free mm/kasan/quarantine.c:157 [inline] qlist_free_all+0x7c/0x132 mm/kasan/quarantine.c:176 kasan_quarantine_reduce+0x14c/0x1c8 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0x5c/0x98 mm/kasan/common.c:446 kasan_slab_alloc include/linux/kasan.h:260 [inline] slab_post_alloc_hook mm/slab.h:732 [inline] slab_alloc_node mm/slub.c:3230 [inline] slab_alloc mm/slub.c:3238 [inline] __kmalloc_track_caller+0x156/0x30e mm/slub.c:4926 kstrdup mm/util.c:60 [inline] kstrdup_const+0x84/0xba mm/util.c:83 __kernfs_new_node+0xc8/0x5f2 fs/kernfs/dir.c:581 kernfs_new_node+0x66/0xbe fs/kernfs/dir.c:647 kernfs_create_link+0x78/0x142 fs/kernfs/symlink.c:39 Memory state around the buggy address: ffffaf800f987e80: 00 00 00 00 ff ff ff ff 00 00 00 00 00 00 00 00 ffffaf800f987f00: 00 00 00 00 ff ff ff ff 00 00 00 00 00 00 00 00 >ffffaf800f987f80: 00 00 00 00 ff ff ff ff 00 00 00 00 00 00 00 00 ^ ffffaf800f988000: f1 f1 f1 f1 00 00 00 f3 f3 f3 f3 f3 00 00 00 00 ffffaf800f988080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================