================================================================== BUG: KASAN: slab-use-after-free in list_empty include/linux/list.h:373 [inline] BUG: KASAN: slab-use-after-free in gfs2_discard fs/gfs2/aops.c:622 [inline] BUG: KASAN: slab-use-after-free in gfs2_invalidate_folio+0x463/0xa50 fs/gfs2/aops.c:660 Read of size 8 at addr ffff88802e4f40f8 by task syz.2.4563/22050 CPU: 1 PID: 22050 Comm: syz.2.4563 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xa8/0x210 mm/kasan/report.c:468 kasan_report+0x117/0x150 mm/kasan/report.c:581 list_empty include/linux/list.h:373 [inline] gfs2_discard fs/gfs2/aops.c:622 [inline] gfs2_invalidate_folio+0x463/0xa50 fs/gfs2/aops.c:660 folio_invalidate mm/truncate.c:158 [inline] truncate_cleanup_folio+0x220/0x5c0 mm/truncate.c:178 truncate_inode_pages_range+0x28a/0xfb0 mm/truncate.c:392 gfs2_evict_inode+0x402/0x1350 fs/gfs2/super.c:1535 evict+0x4ca/0x8d0 fs/inode.c:705 gfs2_evict_inodes fs/gfs2/ops_fstype.c:1770 [inline] gfs2_kill_sb+0x230/0x320 fs/gfs2/ops_fstype.c:1796 deactivate_locked_super+0x97/0x100 fs/super.c:481 cleanup_mnt+0x43b/0x4d0 fs/namespace.c:1259 task_work_run+0x1d4/0x260 kernel/task_work.c:245 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0x95a/0x2460 kernel/exit.c:883 do_group_exit+0x21b/0x2d0 kernel/exit.c:1024 get_signal+0x12fc/0x13f0 kernel/signal.c:2902 arch_do_signal_or_restart+0xc2/0x800 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fca1415d04e Code: Unable to access opcode bytes at 0x7fca1415d024. RSP: 002b:00007fca123f5f58 EFLAGS: 00000246 ORIG_RAX: 00000000000000e6 RAX: fffffffffffffdfc RBX: 00007fca123f66c0 RCX: 00007fca1415d04e RDX: 00007fca123f5fb0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fca14232c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fca14416038 R14: 00007fca14415fa0 R15: 00007ffe8fe17e88 Allocated by task 22305: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4b0 mm/slab.h:767 slab_alloc_node mm/slub.c:3495 [inline] slab_alloc mm/slub.c:3503 [inline] __kmem_cache_alloc_lru mm/slub.c:3510 [inline] kmem_cache_alloc+0x11a/0x2d0 mm/slub.c:3519 kmem_cache_zalloc include/linux/slab.h:711 [inline] gfs2_alloc_bufdata fs/gfs2/trans.c:168 [inline] gfs2_trans_add_data+0x1ff/0x620 fs/gfs2/trans.c:209 gfs2_trans_add_databufs+0x15a/0x1c0 fs/gfs2/aops.c:57 gfs2_iomap_put_folio+0x1be/0x400 fs/gfs2/bmap.c:994 iomap_write_end+0x631/0xb80 fs/iomap/buffered-io.c:885 iomap_write_iter fs/iomap/buffered-io.c:951 [inline] iomap_file_buffered_write+0x751/0xd80 fs/iomap/buffered-io.c:1000 gfs2_file_buffered_write+0x4bd/0x820 fs/gfs2/file.c:1060 gfs2_file_write_iter+0x48d/0xe90 fs/gfs2/file.c:1158 call_write_iter include/linux/fs.h:2018 [inline] aio_write+0x564/0x7d0 fs/aio.c:1593 __io_submit_one fs/aio.c:-1 [inline] io_submit_one+0x73f/0x12a0 fs/aio.c:2012 __do_sys_io_submit fs/aio.c:2071 [inline] __se_sys_io_submit+0x1a1/0x310 fs/aio.c:2041 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Freed by task 22305: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:237 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1811 [inline] slab_free_freelist_hook+0x130/0x1a0 mm/slub.c:1837 slab_free mm/slub.c:3830 [inline] kmem_cache_free+0xf8/0x270 mm/slub.c:3852 trans_drain fs/gfs2/log.c:1022 [inline] gfs2_log_flush+0x1923/0x2500 fs/gfs2/log.c:1162 gfs2_jdata_writepages+0xf9/0x150 fs/gfs2/aops.c:398 do_writepages+0x3b3/0x630 mm/page-writeback.c:2575 filemap_fdatawrite_wbc+0x122/0x180 mm/filemap.c:390 __filemap_fdatawrite_range mm/filemap.c:423 [inline] filemap_fdatawrite_range+0xf7/0x160 mm/filemap.c:441 gfs2_fsync+0xdf/0x350 fs/gfs2/file.c:751 generic_write_sync include/linux/fs.h:2651 [inline] gfs2_file_write_iter+0xcea/0xe90 fs/gfs2/file.c:1160 call_write_iter include/linux/fs.h:2018 [inline] aio_write+0x564/0x7d0 fs/aio.c:1593 __io_submit_one fs/aio.c:-1 [inline] io_submit_one+0x73f/0x12a0 fs/aio.c:2012 __do_sys_io_submit fs/aio.c:2071 [inline] __se_sys_io_submit+0x1a1/0x310 fs/aio.c:2041 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff88802e4f40e0 which belongs to the cache gfs2_bufdata of size 80 The buggy address is located 24 bytes inside of freed 80-byte region [ffff88802e4f40e0, ffff88802e4f4130) The buggy address belongs to the physical page: page:ffffea0000b93d00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2e4f4 flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff888019f8d780 dead000000000122 0000000000000000 raw: 0000000000000000 0000000080240024 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 22297, tgid 22296 (syz.2.4600), ts 1448206605048, free_ts 1447171881759 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1581 prep_new_page mm/page_alloc.c:1588 [inline] get_page_from_freelist+0x1951/0x19e0 mm/page_alloc.c:3220 __alloc_pages+0x1f0/0x460 mm/page_alloc.c:4500 alloc_slab_page+0x5d/0x160 mm/slub.c:1881 allocate_slab mm/slub.c:2028 [inline] new_slab+0x87/0x2d0 mm/slub.c:2081 ___slab_alloc+0xc5d/0x12f0 mm/slub.c:3253 __slab_alloc mm/slub.c:3339 [inline] __slab_alloc_node mm/slub.c:3392 [inline] slab_alloc_node mm/slub.c:3485 [inline] slab_alloc mm/slub.c:3503 [inline] __kmem_cache_alloc_lru mm/slub.c:3510 [inline] kmem_cache_alloc+0x1b3/0x2d0 mm/slub.c:3519 kmem_cache_zalloc include/linux/slab.h:711 [inline] gfs2_alloc_bufdata fs/gfs2/trans.c:168 [inline] gfs2_trans_add_meta+0x30c/0xc20 fs/gfs2/trans.c:251 do_gfs2_set_flags fs/gfs2/file.c:265 [inline] gfs2_fileattr_set+0x732/0x9e0 fs/gfs2/file.c:311 vfs_fileattr_set+0x85d/0xb10 fs/ioctl.c:697 ioctl_setflags fs/ioctl.c:729 [inline] do_vfs_ioctl+0x1449/0x1cc0 fs/ioctl.c:840 __do_sys_ioctl fs/ioctl.c:869 [inline] __se_sys_ioctl+0x83/0x170 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1181 [inline] free_unref_page_prepare+0x7b2/0x8c0 mm/page_alloc.c:2365 free_unref_page_list+0xbe/0x860 mm/page_alloc.c:2504 release_pages+0x1f7a/0x2200 mm/swap.c:1022 __folio_batch_release+0x71/0xe0 mm/swap.c:1042 folio_batch_release include/linux/pagevec.h:83 [inline] truncate_inode_pages_range+0x3b9/0xfb0 mm/truncate.c:396 kill_bdev block/bdev.c:76 [inline] set_blocksize+0x2fa/0x4b0 block/bdev.c:164 sb_set_blocksize+0x4a/0x100 block/bdev.c:178 init_sb+0x9e3/0x1340 fs/gfs2/ops_fstype.c:525 gfs2_fill_super+0x148a/0x1f30 fs/gfs2/ops_fstype.c:1233 get_tree_bdev+0x3f3/0x520 fs/super.c:1591 gfs2_get_tree+0x51/0x1e0 fs/gfs2/ops_fstype.c:1344 vfs_get_tree+0x8c/0x280 fs/super.c:1764 do_new_mount+0x24b/0xa40 fs/namespace.c:3386 do_mount fs/namespace.c:3726 [inline] __do_sys_mount fs/namespace.c:3935 [inline] __se_sys_mount+0x2e7/0x3d0 fs/namespace.c:3912 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Memory state around the buggy address: ffff88802e4f3f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88802e4f4000: fa fb fb fb fb fb fb fb fb fb fc fc fc fc fa fb >ffff88802e4f4080: fb fb fb fb fb fb fb fb fc fc fc fc fa fb fb fb ^ ffff88802e4f4100: fb fb fb fb fb fb fc fc fc fc fa fb fb fb fb fb ffff88802e4f4180: fb fb fb fb fc fc fc fc fa fb fb fb fb fb fb fb ==================================================================