================================================================== BUG: KASAN: slab-out-of-bounds in ext4_ext_binsearch fs/ext4/extents.c:837 [inline] BUG: KASAN: slab-out-of-bounds in ext4_find_extent+0x994/0xb6c fs/ext4/extents.c:953 Read of size 4 at addr ffff0000d49d5e18 by task syz.4.333/5936 CPU: 0 PID: 5936 Comm: syz.4.333 Not tainted 6.1.141-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call trace: dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack+0x30/0x40 lib/dump_stack.c:88 dump_stack_lvl+0xf8/0x160 lib/dump_stack.c:106 print_address_description+0x88/0x220 mm/kasan/report.c:316 print_report+0x50/0x68 mm/kasan/report.c:427 kasan_report+0xa8/0x100 mm/kasan/report.c:531 __asan_report_load4_noabort+0x2c/0x38 mm/kasan/report_generic.c:350 ext4_ext_binsearch fs/ext4/extents.c:837 [inline] ext4_find_extent+0x994/0xb6c fs/ext4/extents.c:953 ext4_ext_map_blocks+0x240/0x559c fs/ext4/extents.c:4165 ext4_map_blocks+0x860/0x1770 fs/ext4/inode.c:679 _ext4_get_block+0x194/0x4c8 fs/ext4/inode.c:822 ext4_get_block+0x4c/0x60 fs/ext4/inode.c:839 ext4_block_write_begin+0x508/0x10f8 fs/ext4/inode.c:1124 ext4_write_begin+0x5ec/0x133c fs/ext4/ext4_jbd2.h:-1 ext4_da_write_begin+0x360/0x9d8 fs/ext4/inode.c:3000 generic_perform_write+0x230/0x4b0 mm/filemap.c:3846 ext4_buffered_write_iter+0x2c4/0x530 fs/ext4/file.c:285 ext4_file_write_iter+0x188/0x152c fs/ext4/file.c:-1 do_iter_readv_writev fs/read_write.c:-1 [inline] do_iter_write+0x530/0x91c fs/read_write.c:861 vfs_iter_write+0x88/0xac fs/read_write.c:902 iter_file_splice_write+0x500/0xa18 fs/splice.c:685 do_splice_from fs/splice.c:763 [inline] direct_splice_actor+0xe4/0x134 fs/splice.c:950 splice_direct_to_actor+0x3b4/0x978 fs/splice.c:896 do_splice_direct+0x158/0x244 fs/splice.c:1002 generic_copy_file_range fs/read_write.c:1393 [inline] vfs_copy_file_range+0x8f0/0x11ec fs/read_write.c:1539 __do_sys_copy_file_range fs/read_write.c:1596 [inline] __se_sys_copy_file_range fs/read_write.c:1559 [inline] __arm64_sys_copy_file_range+0x4f4/0x81c fs/read_write.c:1559 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 Allocated by task 5230: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4c/0x80 mm/kasan/common.c:52 kasan_save_alloc_info+0x28/0x34 mm/kasan/generic.c:505 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0xa0/0xb8 mm/kasan/common.c:383 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slab_common.c:936 [inline] __kmalloc_node_track_caller+0xe0/0x16c mm/slab_common.c:956 kmalloc_reserve net/core/skbuff.c:446 [inline] __alloc_skb+0x264/0x718 net/core/skbuff.c:515 alloc_skb include/linux/skbuff.h:1271 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:748 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline] nsim_dev_trap_report_work+0x214/0x984 drivers/net/netdevsim/dev.c:851 process_one_work+0x7f4/0x13a8 kernel/workqueue.c:2292 worker_thread+0x8c8/0xfbc kernel/workqueue.c:2439 kthread+0x250/0x2d8 kernel/kthread.c:376 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:864 Freed by task 5230: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4c/0x80 mm/kasan/common.c:52 kasan_save_free_info+0x3c/0x60 mm/kasan/generic.c:516 ____kasan_slab_free+0x148/0x1b0 mm/kasan/common.c:236 __kasan_slab_free+0x18/0x28 mm/kasan/common.c:244 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1724 [inline] slab_free_freelist_hook+0x16c/0x1ec mm/slub.c:1750 slab_free mm/slub.c:3661 [inline] __kmem_cache_free+0xc0/0x224 mm/slub.c:3674 kfree+0xd0/0x1ac mm/slab_common.c:988 skb_free_head net/core/skbuff.c:762 [inline] skb_release_data+0x43c/0x648 net/core/skbuff.c:791 skb_release_all net/core/skbuff.c:856 [inline] __kfree_skb net/core/skbuff.c:870 [inline] consume_skb+0xa0/0x104 net/core/skbuff.c:1035 nsim_dev_trap_report drivers/net/netdevsim/dev.c:821 [inline] nsim_dev_trap_report_work+0x630/0x984 drivers/net/netdevsim/dev.c:851 process_one_work+0x7f4/0x13a8 kernel/workqueue.c:2292 worker_thread+0x8c8/0xfbc kernel/workqueue.c:2439 kthread+0x250/0x2d8 kernel/kthread.c:376 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:864 The buggy address belongs to the object at ffff0000d49d4000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 3608 bytes to the right of 4096-byte region [ffff0000d49d4000, ffff0000d49d5000) The buggy address belongs to the physical page: page:00000000d56ddc07 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1149d0 head:00000000d56ddc07 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x5ffc00000010200(slab|head|node=0|zone=2|lastcpupid=0x7ff) raw: 05ffc00000010200 fffffc000371a800 dead000000000002 ffff0000c0002a80 raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000d49d5d00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff0000d49d5d80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff0000d49d5e00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff0000d49d5e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff0000d49d5f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================