================================================================== BUG: KASAN: use-after-free in ext4_ext_binsearch fs/ext4/extents.c:826 [inline] BUG: KASAN: use-after-free in ext4_find_extent+0xbea/0xe30 fs/ext4/extents.c:945 Read of size 4 at addr ffff88812ba54ccc by task syz.2.16/508 CPU: 0 PID: 508 Comm: syz.2.16 Not tainted 5.10.234-syzkaller-1006652-g3f5f2283d684 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack_lvl+0x1e2/0x24b lib/dump_stack.c:118 print_address_description+0x81/0x3b0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:435 [inline] kasan_report+0x179/0x1c0 mm/kasan/report.c:452 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report_generic.c:308 ext4_ext_binsearch fs/ext4/extents.c:826 [inline] ext4_find_extent+0xbea/0xe30 fs/ext4/extents.c:945 ext4_ext_remove_space+0x369/0x4e10 fs/ext4/extents.c:2826 ext4_punch_hole+0x720/0xb10 fs/ext4/inode.c:4216 ext4_fallocate+0x2e8/0x1cc0 fs/ext4/extents.c:4756 vfs_fallocate+0x492/0x570 fs/open.c:310 ksys_fallocate fs/open.c:333 [inline] __do_sys_fallocate fs/open.c:341 [inline] __se_sys_fallocate fs/open.c:339 [inline] __x64_sys_fallocate+0xc0/0x110 fs/open.c:339 do_syscall_64+0x34/0x70 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7f3154cf1de9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f3154764038 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 00007f3154f0afa0 RCX: 00007f3154cf1de9 RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000005 RBP: 00007f3154d732a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000001a00 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f3154f0afa0 R15: 00007ffe3d8bb268 The buggy address belongs to the page: page:ffffea0004ae9500 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x12ba54 flags: 0x4000000000000000() raw: 4000000000000000 ffffea0004ae9548 ffffea0004ae94c8 0000000000000000 raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 0, migratetype Movable, gfp_mask 0x8100dca(GFP_HIGHUSER_MOVABLE|__GFP_ZERO|0x8000000), pid 508, ts 57158033412, free_ts 57159188938 set_page_owner include/linux/page_owner.h:35 [inline] post_alloc_hook mm/page_alloc.c:2456 [inline] prep_new_page+0x166/0x180 mm/page_alloc.c:2462 get_page_from_freelist+0x2d8c/0x2f30 mm/page_alloc.c:4254 __alloc_pages_nodemask+0x435/0xaf0 mm/page_alloc.c:5348 __alloc_pages include/linux/gfp.h:544 [inline] __alloc_pages_node include/linux/gfp.h:557 [inline] alloc_pages_node include/linux/gfp.h:571 [inline] alloc_pages include/linux/gfp.h:590 [inline] do_anonymous_page mm/memory.c:3963 [inline] handle_pte_fault+0x175a/0x3e10 mm/memory.c:4786 ___handle_speculative_fault mm/memory.c:5219 [inline] __handle_speculative_fault+0x1370/0x1e90 mm/memory.c:5268 handle_speculative_fault include/linux/mm.h:1838 [inline] do_user_addr_fault arch/x86/mm/fault.c:1285 [inline] handle_page_fault arch/x86/mm/fault.c:1428 [inline] exc_page_fault+0x234/0x5b0 arch/x86/mm/fault.c:1484 asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:571 page last free stack trace: reset_page_owner include/linux/page_owner.h:28 [inline] free_pages_prepare mm/page_alloc.c:1349 [inline] free_pcp_prepare mm/page_alloc.c:1421 [inline] free_unref_page_prepare+0x2ae/0x2d0 mm/page_alloc.c:3336 free_unref_page_list+0x122/0xb20 mm/page_alloc.c:3443 release_pages+0xea0/0xef0 mm/swap.c:1103 free_pages_and_swap_cache+0x8a/0xa0 mm/swap_state.c:356 tlb_batch_pages_flush mm/mmu_gather.c:49 [inline] tlb_flush_mmu_free mm/mmu_gather.c:240 [inline] tlb_flush_mmu mm/mmu_gather.c:247 [inline] tlb_finish_mmu+0x177/0x320 mm/mmu_gather.c:326 unmap_region+0x31c/0x370 mm/mmap.c:2799 __do_munmap+0x699/0x8c0 mm/mmap.c:3029 __vm_munmap mm/mmap.c:3082 [inline] __do_sys_munmap mm/mmap.c:3108 [inline] __se_sys_munmap+0x120/0x1a0 mm/mmap.c:3104 __x64_sys_munmap+0x5b/0x70 mm/mmap.c:3104 do_syscall_64+0x34/0x70 entry_SYSCALL_64_after_hwframe+0x61/0xcb Memory state around the buggy address: ffff88812ba54b80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88812ba54c00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff88812ba54c80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff88812ba54d00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88812ba54d80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== ------------[ cut here ]------------ kernel BUG at fs/ext4/extents.c:3180! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 0 PID: 508 Comm: syz.2.16 Tainted: G B 5.10.234-syzkaller-1006652-g3f5f2283d684 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 RIP: 0010:ext4_split_extent_at+0x121c/0x1240 fs/ext4/extents.c:3180 Code: fe c1 38 c1 0f 8c 16 fa ff ff e8 cf b7 cf ff 48 8b 54 24 58 48 8b 74 24 40 e9 02 fa ff ff e8 1b 18 92 ff 0f 0b e8 14 18 92 ff <0f> 0b e8 0d 18 92 ff 0f 0b e8 66 4f d5 02 e8 01 18 92 ff 0f 0b e8 RSP: 0018:ffffc90003337820 EFLAGS: 00010293 RAX: ffffffff81d8a74c RBX: 0000000000000000 RCX: ffff8881287862c0 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90003337990 R08: ffffffff81d897b2 R09: ffffc90003337920 R10: fffff52000666f25 R11: dffffc0000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 1ffff1102574a7ff R15: 0000000000000000 FS: 00007f31547646c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055ab77547cd0 CR3: 00000001175a7000 CR4: 00000000003506b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ext4_force_split_extent_at fs/ext4/extents.c:318 [inline] ext4_ext_remove_space+0x719/0x4e10 fs/ext4/extents.c:2873 ext4_punch_hole+0x720/0xb10 fs/ext4/inode.c:4216 ext4_fallocate+0x2e8/0x1cc0 fs/ext4/extents.c:4756 vfs_fallocate+0x492/0x570 fs/open.c:310 ksys_fallocate fs/open.c:333 [inline] __do_sys_fallocate fs/open.c:341 [inline] __se_sys_fallocate fs/open.c:339 [inline] __x64_sys_fallocate+0xc0/0x110 fs/open.c:339 do_syscall_64+0x34/0x70 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7f3154cf1de9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f3154764038 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 00007f3154f0afa0 RCX: 00007f3154cf1de9 RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000005 RBP: 00007f3154d732a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000001a00 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f3154f0afa0 R15: 00007ffe3d8bb268 Modules linked in: ---[ end trace 8886935b01b82124 ]--- RIP: 0010:ext4_split_extent_at+0x121c/0x1240 fs/ext4/extents.c:3180 Code: fe c1 38 c1 0f 8c 16 fa ff ff e8 cf b7 cf ff 48 8b 54 24 58 48 8b 74 24 40 e9 02 fa ff ff e8 1b 18 92 ff 0f 0b e8 14 18 92 ff <0f> 0b e8 0d 18 92 ff 0f 0b e8 66 4f d5 02 e8 01 18 92 ff 0f 0b e8 RSP: 0018:ffffc90003337820 EFLAGS: 00010293 RAX: ffffffff81d8a74c RBX: 0000000000000000 RCX: ffff8881287862c0 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90003337990 R08: ffffffff81d897b2 R09: ffffc90003337920 R10: fffff52000666f25 R11: dffffc0000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 1ffff1102574a7ff R15: 0000000000000000 FS: 00007f31547646c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3154cd5220 CR3: 00000001175a7000 CR4: 00000000003506a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400