================================================================== BUG: KASAN: use-after-free in prog_list_prog kernel/bpf/cgroup.c:174 [inline] BUG: KASAN: use-after-free in prog_list_length kernel/bpf/cgroup.c:187 [inline] BUG: KASAN: use-after-free in compute_effective_progs+0x1d3/0x6e0 kernel/bpf/cgroup.c:240 Read of size 8 at addr ffff888144017298 by task syz-executor.2/24782 CPU: 1 PID: 24782 Comm: syz-executor.2 Tainted: G W 5.10.118-syzkaller-00163-gfa7f6a5f56d9 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/29/2022 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack_lvl+0x1e2/0x24b lib/dump_stack.c:118 print_address_description+0x81/0x3c0 mm/kasan/report.c:233 __kasan_report mm/kasan/report.c:419 [inline] kasan_report+0x1a4/0x1f0 mm/kasan/report.c:436 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:309 prog_list_prog kernel/bpf/cgroup.c:174 [inline] prog_list_length kernel/bpf/cgroup.c:187 [inline] compute_effective_progs+0x1d3/0x6e0 kernel/bpf/cgroup.c:240 update_effective_progs+0x79/0x320 kernel/bpf/cgroup.c:343 __cgroup_bpf_detach+0x312/0x570 kernel/bpf/cgroup.c:689 bpf_cgroup_link_release+0x94/0x260 kernel/bpf/cgroup.c:833 bpf_link_free kernel/bpf/syscall.c:2350 [inline] bpf_link_put+0x1e9/0x270 kernel/bpf/syscall.c:2376 bpf_link_release+0x3b/0x40 kernel/bpf/syscall.c:2384 __fput+0x348/0x7c0 fs/file_table.c:281 ____fput+0x15/0x20 fs/file_table.c:314 task_work_run+0x147/0x1b0 kernel/task_work.c:154 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_user_mode_loop+0xc8/0xe0 kernel/entry/common.c:164 exit_to_user_mode_prepare kernel/entry/common.c:191 [inline] syscall_exit_to_user_mode+0x77/0xa0 kernel/entry/common.c:266 do_syscall_64+0x40/0x70 arch/x86/entry/common.c:56 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f7e5127fd4b Code: 0f 05 48 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8 63 fc ff ff 8b 7c 24 0c 41 89 c0 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 0c e8 a1 fc ff ff 8b 44 RSP: 002b:00007ffc73e7d860 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000006 RCX: 00007f7e5127fd4b RDX: 0000000000000000 RSI: 0000001b33121b1c RDI: 0000000000000005 RBP: 00007f7e513e1960 R08: 0000000000000000 R09: 00000000eaf814b6 R10: 0000000000000000 R11: 0000000000000293 R12: 000000000021f529 R13: 00007ffc73e7d960 R14: 00007ffc73e7d980 R15: 0000000000000032 Allocated by task 24784: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:428 [inline] ____kasan_kmalloc+0xdc/0x110 mm/kasan/common.c:507 __kasan_kmalloc+0x9/0x10 mm/kasan/common.c:516 kasan_kmalloc include/linux/kasan.h:269 [inline] kmem_cache_alloc_trace+0x1dd/0x330 mm/slub.c:2983 kmalloc include/linux/slab.h:552 [inline] kzalloc include/linux/slab.h:664 [inline] cgroup_bpf_link_attach+0x12e/0x4a0 kernel/bpf/cgroup.c:918 link_create+0x540/0x6e0 kernel/bpf/syscall.c:4092 __do_sys_bpf+0x528/0x6c0 kernel/bpf/syscall.c:4497 __se_sys_bpf kernel/bpf/syscall.c:4383 [inline] __x64_sys_bpf+0x7a/0x90 kernel/bpf/syscall.c:4383 do_syscall_64+0x34/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 24784: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4c/0x80 mm/kasan/common.c:46 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:357 ____kasan_slab_free+0x121/0x160 mm/kasan/common.c:360 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:368 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:1604 [inline] slab_free_freelist_hook+0xcc/0x1a0 mm/slub.c:1630 slab_free mm/slub.c:3212 [inline] kfree+0xc3/0x290 mm/slub.c:4200 bpf_cgroup_link_dealloc+0x15/0x20 kernel/bpf/cgroup.c:849 bpf_link_free kernel/bpf/syscall.c:2354 [inline] bpf_link_put+0x243/0x270 kernel/bpf/syscall.c:2376 bpf_link_release+0x3b/0x40 kernel/bpf/syscall.c:2384 __fput+0x348/0x7c0 fs/file_table.c:281 ____fput+0x15/0x20 fs/file_table.c:314 task_work_run+0x147/0x1b0 kernel/task_work.c:154 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_user_mode_loop+0xc8/0xe0 kernel/entry/common.c:164 exit_to_user_mode_prepare kernel/entry/common.c:191 [inline] syscall_exit_to_user_mode+0x77/0xa0 kernel/entry/common.c:266 do_syscall_64+0x40/0x70 arch/x86/entry/common.c:56 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The buggy address belongs to the object at ffff888144017280 which belongs to the cache kmalloc-96 of size 96 The buggy address is located 24 bytes inside of 96-byte region [ffff888144017280, ffff8881440172e0) The buggy address belongs to the page: page:ffffea00051005c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888144017c80 pfn:0x144017 flags: 0x8000000000000200(slab) raw: 8000000000000200 ffffea000418f240 0000000500000005 ffff888100043680 raw: ffff888144017c80 000000008020001a 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x112c40(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY|__GFP_HARDWALL), pid 9085, ts 398176783118, free_ts 398029832256 set_page_owner include/linux/page_owner.h:35 [inline] post_alloc_hook mm/page_alloc.c:2385 [inline] prep_new_page mm/page_alloc.c:2391 [inline] get_page_from_freelist+0x745/0x760 mm/page_alloc.c:4067 __alloc_pages_nodemask+0x3b6/0x890 mm/page_alloc.c:5117 alloc_slab_page mm/slub.c:1815 [inline] allocate_slab+0x78/0x540 mm/slub.c:1817 new_slab mm/slub.c:1878 [inline] new_slab_objects mm/slub.c:2637 [inline] ___slab_alloc+0x131/0x2e0 mm/slub.c:2800 __slab_alloc+0x63/0xa0 mm/slub.c:2840 slab_alloc_node mm/slub.c:2922 [inline] slab_alloc mm/slub.c:2964 [inline] __kmalloc+0x24f/0x360 mm/slub.c:4038 kmalloc_array include/linux/slab.h:592 [inline] kcalloc include/linux/slab.h:603 [inline] ext4_find_extent+0x249/0xd80 fs/ext4/extents.c:902 ext4_ext_map_blocks+0x219/0x3a30 fs/ext4/extents.c:4093 ext4_map_blocks+0xa93/0x1ee0 fs/ext4/inode.c:638 ext4_iomap_alloc fs/ext4/inode.c:3487 [inline] ext4_iomap_begin+0x7ed/0xc00 fs/ext4/inode.c:3537 iomap_apply+0xf9/0x7f0 fs/iomap/apply.c:46 __iomap_dio_rw+0x716/0x10d0 fs/iomap/direct-io.c:523 iomap_dio_rw+0x35/0x80 fs/iomap/direct-io.c:611 ext4_dio_write_iter fs/ext4/file.c:571 [inline] ext4_file_write_iter+0x105d/0x1cd0 fs/ext4/file.c:681 do_iter_readv_writev+0x52a/0x720 fs/read_write.c:737 do_iter_write+0x182/0x660 fs/read_write.c:866 page last free stack trace: reset_page_owner include/linux/page_owner.h:28 [inline] free_pages_prepare mm/page_alloc.c:1331 [inline] free_pcp_prepare+0x18c/0x1c0 mm/page_alloc.c:1405 free_unref_page_prepare mm/page_alloc.c:3291 [inline] free_unref_page_list+0x11d/0x660 mm/page_alloc.c:3365 release_pages+0xb14/0xb50 mm/swap.c:1081 free_pages_and_swap_cache+0x97/0xb0 mm/swap_state.c:356 tlb_batch_pages_flush mm/mmu_gather.c:49 [inline] tlb_flush_mmu_free mm/mmu_gather.c:242 [inline] tlb_flush_mmu+0x8a0/0xa80 mm/mmu_gather.c:249 tlb_finish_mmu+0xd2/0x1f0 mm/mmu_gather.c:328 exit_mmap+0x319/0x5c0 mm/mmap.c:3320 __mmput+0x95/0x2c0 kernel/fork.c:1133 mmput+0x4b/0x50 kernel/fork.c:1154 exit_mm+0x5cd/0x790 kernel/exit.c:489 do_exit+0x614/0x2360 kernel/exit.c:800 do_group_exit+0x13a/0x300 kernel/exit.c:910 get_signal+0xe17/0x1440 kernel/signal.c:2781 arch_do_signal+0x8e/0x650 arch/x86/kernel/signal.c:805 exit_to_user_mode_loop+0xa3/0xe0 kernel/entry/common.c:161 exit_to_user_mode_prepare kernel/entry/common.c:191 [inline] syscall_exit_to_user_mode+0x77/0xa0 kernel/entry/common.c:266 Memory state around the buggy address: ffff888144017180: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc ffff888144017200: 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc >ffff888144017280: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ^ ffff888144017300: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff888144017380: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ==================================================================