================================================================== BUG: KASAN: slab-out-of-bounds in ext4_ext_binsearch fs/ext4/extents.c:827 [inline] BUG: KASAN: slab-out-of-bounds in ext4_find_extent+0xbeb/0xe20 fs/ext4/extents.c:946 Read of size 4 at addr ffff8881109da08c by task kworker/u4:63/7444 CPU: 1 PID: 7444 Comm: kworker/u4:63 Not tainted 5.15.189-syzkaller-00091-gf32b52534f1d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Workqueue: writeback wb_workfn (flush-7:6) Call Trace: __dump_stack+0x21/0x30 lib/dump_stack.c:88 dump_stack_lvl+0xee/0x150 lib/dump_stack.c:106 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:427 [inline] kasan_report+0xf1/0x140 mm/kasan/report.c:444 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report_generic.c:308 ext4_ext_binsearch fs/ext4/extents.c:827 [inline] ext4_find_extent+0xbeb/0xe20 fs/ext4/extents.c:946 ext4_ext_map_blocks+0x1de/0x6280 fs/ext4/extents.c:4166 ext4_map_blocks+0x97b/0x1b20 fs/ext4/inode.c:674 mpage_map_one_extent fs/ext4/inode.c:2421 [inline] mpage_map_and_submit_extent fs/ext4/inode.c:2474 [inline] ext4_writepages+0x11e7/0x2f90 fs/ext4/inode.c:2842 do_writepages+0x48a/0x6c0 mm/page-writeback.c:2388 __writeback_single_inode+0xd5/0x9c0 fs/fs-writeback.c:1647 writeback_sb_inodes+0x9c0/0x1590 fs/fs-writeback.c:1930 wb_writeback+0x3f1/0x980 fs/fs-writeback.c:2106 wb_do_writeback fs/fs-writeback.c:2253 [inline] wb_workfn+0x38f/0xe20 fs/fs-writeback.c:2294 process_one_work+0x6be/0xba0 kernel/workqueue.c:2325 worker_thread+0xa59/0x1200 kernel/workqueue.c:2472 kthread+0x411/0x500 kernel/kthread.c:337 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Allocated by task 7149: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:433 [inline] ____kasan_kmalloc mm/kasan/common.c:512 [inline] __kasan_kmalloc+0xda/0x110 mm/kasan/common.c:521 kasan_kmalloc include/linux/kasan.h:227 [inline] kmem_cache_alloc_trace+0x119/0x270 mm/slub.c:3269 kmalloc include/linux/slab.h:616 [inline] __hw_addr_create net/core/dev_addr_lists.c:29 [inline] __hw_addr_add_ex+0x205/0x800 net/core/dev_addr_lists.c:93 __dev_mc_add net/core/dev_addr_lists.c:832 [inline] dev_mc_add+0x74/0xd0 net/core/dev_addr_lists.c:850 igmp6_group_added+0x1a3/0x590 net/ipv6/mcast.c:680 __ipv6_dev_mc_inc+0x81f/0xa00 net/ipv6/mcast.c:949 ipv6_dev_mc_inc+0x1f/0x30 net/ipv6/mcast.c:957 br_ip6_multicast_join_snoopers net/bridge/br_multicast.c:3999 [inline] br_multicast_join_snoopers+0x1c4/0x240 net/bridge/br_multicast.c:4010 br_dev_open+0xce/0xe0 net/bridge/br_device.c:186 __dev_open+0x33f/0x4c0 net/core/dev.c:1545 __dev_change_flags+0x20a/0x6a0 net/core/dev.c:8861 rtnl_configure_link+0x16d/0x330 net/core/rtnetlink.c:3179 __rtnl_newlink net/core/rtnetlink.c:3532 [inline] rtnl_newlink+0x1358/0x17b0 net/core/rtnetlink.c:3572 rtnetlink_rcv_msg+0x9e4/0xb90 net/core/rtnetlink.c:5650 netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2511 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5668 netlink_unicast_kernel net/netlink/af_netlink.c:1322 [inline] netlink_unicast+0x876/0xa40 net/netlink/af_netlink.c:1348 netlink_sendmsg+0x86a/0xb70 net/netlink/af_netlink.c:1922 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] ____sys_sendmsg+0x5a2/0x8c0 net/socket.c:2436 ___sys_sendmsg+0x1f0/0x260 net/socket.c:2490 __sys_sendmsg net/socket.c:2519 [inline] __do_sys_sendmsg net/socket.c:2528 [inline] __se_sys_sendmsg net/socket.c:2526 [inline] __x64_sys_sendmsg+0x1e2/0x2a0 net/socket.c:2526 x64_sys_call+0x4b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:47 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 The buggy address belongs to the object at ffff8881109da000 which belongs to the cache kmalloc-128 of size 128 The buggy address is located 12 bytes to the right of 128-byte region [ffff8881109da000, ffff8881109da080) The buggy address belongs to the page: page:ffffea0004427680 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8881109da400 pfn:0x1109da flags: 0x4000000000000200(slab|zone=1) raw: 4000000000000200 ffffea00042e0388 ffffea00042b2008 ffff888100042a80 raw: ffff8881109da400 0000000000100009 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 0x112a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_HARDWALL), pid 5314, ts 326725537377, free_ts 326718095683 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x192/0x1b0 mm/page_alloc.c:2605 prep_new_page+0x1c/0x110 mm/page_alloc.c:2611 get_page_from_freelist+0x2cc5/0x2d50 mm/page_alloc.c:4485 __alloc_pages+0x18f/0x440 mm/page_alloc.c:5795 alloc_slab_page mm/slub.c:-1 [inline] allocate_slab mm/slub.c:1932 [inline] new_slab+0xa1/0x4d0 mm/slub.c:1995 ___slab_alloc+0x381/0x810 mm/slub.c:3028 __slab_alloc+0x49/0x90 mm/slub.c:3115 slab_alloc_node mm/slub.c:3206 [inline] slab_alloc mm/slub.c:3250 [inline] kmem_cache_alloc_trace+0x146/0x270 mm/slub.c:3267 kmalloc include/linux/slab.h:616 [inline] __hw_addr_create net/core/dev_addr_lists.c:29 [inline] __hw_addr_add_ex+0x205/0x800 net/core/dev_addr_lists.c:93 __dev_mc_add net/core/dev_addr_lists.c:832 [inline] dev_mc_add+0x74/0xd0 net/core/dev_addr_lists.c:850 igmp6_group_added+0x1a3/0x590 net/ipv6/mcast.c:680 __ipv6_dev_mc_inc+0x81f/0xa00 net/ipv6/mcast.c:949 ipv6_dev_mc_inc+0x1f/0x30 net/ipv6/mcast.c:957 addrconf_join_solict net/ipv6/addrconf.c:2202 [inline] addrconf_dad_begin net/ipv6/addrconf.c:4037 [inline] addrconf_dad_work+0x3d0/0x1540 net/ipv6/addrconf.c:4164 process_one_work+0x6be/0xba0 kernel/workqueue.c:2325 worker_thread+0xa59/0x1200 kernel/workqueue.c:2472 page last free stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] free_pages_prepare mm/page_alloc.c:1472 [inline] free_pcp_prepare mm/page_alloc.c:1544 [inline] free_unref_page_prepare+0x542/0x550 mm/page_alloc.c:3534 free_unref_page+0xa2/0x550 mm/page_alloc.c:3616 free_the_page mm/page_alloc.c:805 [inline] __free_pages+0x6c/0x100 mm/page_alloc.c:5871 free_pages+0x82/0x90 mm/page_alloc.c:5882 kasan_depopulate_vmalloc_pte+0x6b/0x90 mm/kasan/shadow.c:354 apply_to_pte_range mm/memory.c:2643 [inline] apply_to_pmd_range mm/memory.c:2687 [inline] apply_to_pud_range mm/memory.c:2723 [inline] apply_to_p4d_range mm/memory.c:2759 [inline] __apply_to_page_range+0x8b0/0xbf0 mm/memory.c:2795 apply_to_existing_page_range+0x38/0x50 mm/memory.c:2828 kasan_release_vmalloc+0x97/0xb0 mm/kasan/shadow.c:464 __purge_vmap_area_lazy+0xc05/0x1840 mm/vmalloc.c:1716 _vm_unmap_aliases+0x2fd/0x380 mm/vmalloc.c:2119 vm_remove_mappings mm/vmalloc.c:2612 [inline] __vunmap+0x66e/0x9e0 mm/vmalloc.c:2643 __vfree mm/vmalloc.c:2702 [inline] vfree+0x8b/0xc0 mm/vmalloc.c:2733 module_memfree+0x17/0x30 kernel/module.c:2150 bpf_jit_free_exec+0x15/0x20 kernel/bpf/core.c:871 bpf_jit_binary_free kernel/bpf/core.c:918 [inline] bpf_jit_free+0x98/0x240 kernel/bpf/core.c:931 bpf_prog_free_deferred+0x5c7/0x6d0 kernel/bpf/core.c:2302 Memory state around the buggy address: ffff8881109d9f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8881109da000: 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc >ffff8881109da080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8881109da100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881109da180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== EXT4-fs error (device loop6): ext4_map_blocks:740: inode #15: block 203105482985183: comm kworker/u4:63: lblock 0 mapped to illegal pblock 203105482985183 (length 1) EXT4-fs (loop6): Delayed block allocation failed for inode 15 at logical offset 0 with max blocks 1 with error 117 EXT4-fs (loop6): This should not happen!! Data will be lost