================================================================== BUG: KASAN: slab-out-of-bounds in ext4_ext_binsearch fs/ext4/extents.c:840 [inline] BUG: KASAN: slab-out-of-bounds in ext4_find_extent+0xae6/0xcc0 fs/ext4/extents.c:955 Read of size 4 at addr ffff888033db5018 by task syz.4.14/5979 CPU: 1 UID: 0 PID: 5979 Comm: syz.4.14 Not tainted 6.15.0-rc6-syzkaller-00080-g1a80a098c606 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xb4/0x290 mm/kasan/report.c:521 kasan_report+0x118/0x150 mm/kasan/report.c:634 ext4_ext_binsearch fs/ext4/extents.c:840 [inline] ext4_find_extent+0xae6/0xcc0 fs/ext4/extents.c:955 ext4_ext_map_blocks+0x26f/0x67c0 fs/ext4/extents.c:4205 ext4_map_query_blocks+0x99/0x2a0 fs/ext4/inode.c:472 ext4_map_blocks+0x38e/0x1740 fs/ext4/inode.c:670 _ext4_get_block+0x200/0x4c0 fs/ext4/inode.c:785 ext4_get_block_unwritten+0x2e/0x100 fs/ext4/inode.c:818 ext4_block_write_begin+0x543/0x1290 fs/ext4/inode.c:1067 ext4_write_begin+0x6f6/0x12c0 fs/ext4/ext4_jbd2.h:-1 ext4_da_write_begin+0x33a/0xa60 fs/ext4/inode.c:2932 generic_perform_write+0x2c4/0x910 mm/filemap.c:4103 ext4_buffered_write_iter+0xce/0x3a0 fs/ext4/file.c:299 ext4_file_write_iter+0x298/0x1bc0 fs/ext4/file.c:-1 new_sync_write fs/read_write.c:591 [inline] vfs_write+0x548/0xa90 fs/read_write.c:684 ksys_pwrite64 fs/read_write.c:791 [inline] __do_sys_pwrite64 fs/read_write.c:799 [inline] __se_sys_pwrite64 fs/read_write.c:796 [inline] __x64_sys_pwrite64+0x193/0x220 fs/read_write.c:796 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f733bd8e969 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:00007f7339bf6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000012 RAX: ffffffffffffffda RBX: 00007f733bfb5fa0 RCX: 00007f733bd8e969 RDX: 000000000000fdef RSI: 0000200000000140 RDI: 0000000000000006 RBP: 00007f733be10ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000fecc R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f733bfb5fa0 R15: 00007ffca66f4398 Allocated by task 5189: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4358 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] uevent_show+0x15a/0x310 drivers/base/core.c:2754 dev_attr_show+0x58/0xc0 drivers/base/core.c:2424 sysfs_kf_seq_show+0x310/0x490 fs/sysfs/file.c:65 seq_read_iter+0x4ea/0xe10 fs/seq_file.c:230 new_sync_read fs/read_write.c:489 [inline] vfs_read+0x4cd/0x980 fs/read_write.c:570 ksys_read+0x145/0x250 fs/read_write.c:713 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 5189: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2380 [inline] slab_free mm/slub.c:4642 [inline] kfree+0x193/0x440 mm/slub.c:4841 uevent_show+0x1d5/0x310 drivers/base/core.c:2767 dev_attr_show+0x58/0xc0 drivers/base/core.c:2424 sysfs_kf_seq_show+0x310/0x490 fs/sysfs/file.c:65 seq_read_iter+0x4ea/0xe10 fs/seq_file.c:230 new_sync_read fs/read_write.c:489 [inline] vfs_read+0x4cd/0x980 fs/read_write.c:570 ksys_read+0x145/0x250 fs/read_write.c:713 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888033db4000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 24 bytes to the right of allocated 4096-byte region [ffff888033db4000, ffff888033db5000) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x33db0 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801a042140 ffffea0000d2b200 dead000000000002 raw: 0000000000000000 0000000000040004 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801a042140 ffffea0000d2b200 dead000000000002 head: 0000000000000000 0000000000040004 00000000f5000000 0000000000000000 head: 00fff00000000003 ffffea0000cf6c01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5474, tgid 5474 (ifup), ts 61188244806, free_ts 61033076798 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1d8/0x230 mm/page_alloc.c:1718 prep_new_page mm/page_alloc.c:1726 [inline] get_page_from_freelist+0x21c7/0x22a0 mm/page_alloc.c:3688 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4970 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2301 alloc_slab_page mm/slub.c:2450 [inline] allocate_slab+0x8a/0x3b0 mm/slub.c:2618 new_slab mm/slub.c:2672 [inline] ___slab_alloc+0xbfc/0x1480 mm/slub.c:3858 __slab_alloc mm/slub.c:3948 [inline] __slab_alloc_node mm/slub.c:4023 [inline] slab_alloc_node mm/slub.c:4184 [inline] __do_kmalloc_node mm/slub.c:4326 [inline] __kmalloc_noprof+0x305/0x4f0 mm/slub.c:4339 kmalloc_noprof include/linux/slab.h:909 [inline] tomoyo_realpath_from_path+0xe3/0x5d0 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_check_open_permission+0x1c1/0x3b0 security/tomoyo/file.c:771 security_file_open+0xb1/0x270 security/security.c:3114 do_dentry_open+0x35e/0x1970 fs/open.c:933 vfs_open+0x3b/0x340 fs/open.c:1086 do_open fs/namei.c:3880 [inline] path_openat+0x2ee5/0x3830 fs/namei.c:4039 do_filp_open+0x1fa/0x410 fs/namei.c:4066 do_sys_openat2+0x121/0x1c0 fs/open.c:1429 do_sys_open fs/open.c:1444 [inline] __do_sys_openat fs/open.c:1460 [inline] __se_sys_openat fs/open.c:1455 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1455 page last free pid 5471 tgid 5471 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1262 [inline] __free_frozen_pages+0xb05/0xcd0 mm/page_alloc.c:2725 __slab_free+0x326/0x400 mm/slub.c:4553 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4147 [inline] slab_alloc_node mm/slub.c:4196 [inline] __do_kmalloc_node mm/slub.c:4326 [inline] __kmalloc_noprof+0x224/0x4f0 mm/slub.c:4339 kmalloc_noprof include/linux/slab.h:909 [inline] tomoyo_add_entry security/tomoyo/common.c:2132 [inline] tomoyo_supervisor+0xbd5/0x1480 security/tomoyo/common.c:2204 tomoyo_audit_path_log security/tomoyo/file.c:168 [inline] tomoyo_path_permission+0x25a/0x380 security/tomoyo/file.c:587 tomoyo_path_perm+0x392/0x4b0 security/tomoyo/file.c:838 security_inode_getattr+0x12f/0x330 security/security.c:2377 vfs_getattr fs/stat.c:256 [inline] vfs_fstat fs/stat.c:278 [inline] __do_sys_newfstat fs/stat.c:546 [inline] __se_sys_newfstat fs/stat.c:543 [inline] __x64_sys_newfstat+0xfe/0x200 fs/stat.c:543 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff888033db4f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888033db4f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888033db5000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff888033db5080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888033db5100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================