RBP: 00007f4d9cf7ec91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000002000402 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f4d9d162038 R14: 00007f4d9d161fa0 R15: 00007ffdb9d835d8 ---[ end trace 9b37bca0cd123caa ]--- ================================================================== BUG: KASAN: slab-out-of-bounds in __set_sit_entry_type fs/f2fs/segment.c:2257 [inline] BUG: KASAN: slab-out-of-bounds in reset_curseg+0x4dd/0x560 fs/f2fs/segment.c:2663 Read of size 4 at addr ffff88811e852bc0 by task syz.4.2155/7735 CPU: 1 PID: 7735 Comm: syz.4.2155 Tainted: G W syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: __dump_stack+0x21/0x24 lib/dump_stack.c:77 dump_stack_lvl+0x1a7/0x208 lib/dump_stack.c:118 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:435 [inline] kasan_report+0xe2/0x130 mm/kasan/report.c:452 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report_generic.c:308 __set_sit_entry_type fs/f2fs/segment.c:2257 [inline] reset_curseg+0x4dd/0x560 fs/f2fs/segment.c:2663 new_curseg+0x12e8/0x1880 fs/f2fs/segment.c:2723 __allocate_new_segment+0x13d/0x810 fs/f2fs/segment.c:3039 __allocate_new_section fs/f2fs/segment.c:3047 [inline] f2fs_allocate_new_section+0x1f3/0x290 fs/f2fs/segment.c:3054 expand_inode_data+0x5f7/0x9a0 fs/f2fs/file.c:1761 f2fs_fallocate+0x42b/0x7e0 fs/f2fs/file.c:1866 vfs_fallocate+0x4b4/0x590 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+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7f4d9cee8819 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f4d9b943028 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 00007f4d9d161fa0 RCX: 00007f4d9cee8819 RDX: 0000000000000bf5 RSI: 0000000000000000 RDI: 0000000000000006 RBP: 00007f4d9cf7ec91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000002000402 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f4d9d162038 R14: 00007f4d9d161fa0 R15: 00007ffdb9d835d8 Allocated by task 7735: 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:430 [inline] ____kasan_kmalloc mm/kasan/common.c:509 [inline] __kasan_kmalloc+0xda/0x110 mm/kasan/common.c:518 kasan_kmalloc include/linux/kasan.h:254 [inline] __kmalloc+0x1a4/0x330 mm/slub.c:4038 __kmalloc_node include/linux/slab.h:421 [inline] kmalloc_node include/linux/slab.h:578 [inline] kvmalloc_node+0x88/0x130 mm/util.c:612 kvmalloc include/linux/mm.h:833 [inline] f2fs_kvmalloc fs/f2fs/f2fs.h:3372 [inline] f2fs_kvzalloc fs/f2fs/f2fs.h:3378 [inline] build_sit_info fs/f2fs/segment.c:4395 [inline] f2fs_build_segment_manager+0xdba/0x4900 fs/f2fs/segment.c:5258 f2fs_fill_super+0x4a3a/0x73f0 fs/f2fs/super.c:4317 mount_bdev+0x28b/0x3a0 fs/super.c:1442 f2fs_mount+0x34/0x40 fs/f2fs/super.c:4598 legacy_get_tree+0xed/0x190 fs/fs_context.c:593 vfs_get_tree+0x89/0x260 fs/super.c:1572 do_new_mount+0x25a/0xa20 fs/namespace.c:3006 path_mount+0x585/0xc90 fs/namespace.c:3336 do_mount fs/namespace.c:3349 [inline] __do_sys_mount fs/namespace.c:3557 [inline] __se_sys_mount+0x320/0x390 fs/namespace.c:3534 __x64_sys_mount+0xbf/0xd0 fs/namespace.c:3534 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb Last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:38 __kasan_record_aux_stack+0xd2/0x100 mm/kasan/generic.c:348 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:358 __call_rcu kernel/rcu/tree.c:2980 [inline] call_rcu+0x11a/0x10b0 kernel/rcu/tree.c:3054 in6_dev_finish_destroy+0x147/0x180 net/ipv6/addrconf_core.c:271 in6_dev_put include/net/addrconf.h:420 [inline] addrconf_ifdown+0x165c/0x1850 net/ipv6/addrconf.c:3943 addrconf_notify+0x3bd/0xe90 net/ipv6/addrconf.c:-1 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0x90/0x100 kernel/notifier.c:410 call_netdevice_notifiers_info net/core/dev.c:2054 [inline] call_netdevice_notifiers_extack net/core/dev.c:2066 [inline] call_netdevice_notifiers net/core/dev.c:2080 [inline] unregister_netdevice_many+0x1074/0x1a80 net/core/dev.c:10780 default_device_exit_batch+0x35e/0x3c0 net/core/dev.c:11300 ops_exit_list net/core/net_namespace.c:190 [inline] cleanup_net+0x603/0xb80 net/core/net_namespace.c:609 process_one_work+0x6e1/0xba0 kernel/workqueue.c:2301 worker_thread+0xa6a/0x13c0 kernel/workqueue.c:2447 kthread+0x346/0x3d0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 The buggy address belongs to the object at ffff88811e852800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 960 bytes inside of 1024-byte region [ffff88811e852800, ffff88811e852c00) The buggy address belongs to the page: page:ffffea00047a1400 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88811e856800 pfn:0x11e850 head:ffffea00047a1400 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x4000000000010200(slab|head) raw: 4000000000010200 ffffea0004a0d408 ffffea0004972608 ffff888100042f00 raw: ffff88811e856800 000000000010000b 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 0, ts 22008138969, free_ts 21425020852 set_page_owner include/linux/page_owner.h:35 [inline] post_alloc_hook mm/page_alloc.c:2456 [inline] prep_new_page+0x179/0x180 mm/page_alloc.c:2462 get_page_from_freelist+0x223b/0x23d0 mm/page_alloc.c:4254 __alloc_pages_nodemask+0x290/0x620 mm/page_alloc.c:5384 alloc_slab_page mm/slub.c:-1 [inline] allocate_slab mm/slub.c:1813 [inline] new_slab+0x84/0x3f0 mm/slub.c:1874 new_slab_objects mm/slub.c:2632 [inline] ___slab_alloc+0x2a6/0x450 mm/slub.c:2796 __slab_alloc+0x63/0xa0 mm/slub.c:2836 slab_alloc_node mm/slub.c:2918 [inline] slab_alloc mm/slub.c:2960 [inline] __kmalloc_track_caller+0x1ec/0x320 mm/slub.c:4541 __kmalloc_reserve net/core/skbuff.c:144 [inline] __alloc_skb+0xdc/0x520 net/core/skbuff.c:212 alloc_skb include/linux/skbuff.h:1126 [inline] __tcp_send_ack+0x9b/0x650 net/ipv4/tcp_output.c:3995 tcp_send_ack+0x3b/0x60 net/ipv4/tcp_output.c:4027 __tcp_ack_snd_check+0x3fd/0x8f0 net/ipv4/tcp_input.c:5538 tcp_rcv_established+0x11d9/0x19f0 net/ipv4/tcp_input.c:5973 tcp_v4_do_rcv+0x4c1/0x7c0 net/ipv4/tcp_ipv4.c:1698 tcp_v4_rcv+0x21b3/0x2720 net/ipv4/tcp_ipv4.c:2094 ip_protocol_deliver_rcu+0x2f0/0x640 net/ipv4/ip_input.c:204 ip_local_deliver_finish net/ipv4/ip_input.c:231 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_local_deliver+0x2e2/0x570 net/ipv4/ip_input.c:252 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+0x2b7/0x2d0 mm/page_alloc.c:3336 free_unref_page mm/page_alloc.c:3391 [inline] free_the_page mm/page_alloc.c:5443 [inline] __free_pages+0x146/0x3b0 mm/page_alloc.c:5454 __vunmap+0x86d/0x9f0 mm/vmalloc.c:2307 __vfree mm/vmalloc.c:2356 [inline] vfree+0x61/0x90 mm/vmalloc.c:2387 kcov_mmap+0x8f/0x130 kernel/kcov.c:489 call_mmap include/linux/fs.h:2071 [inline] mmap_file+0x60/0xb0 mm/util.c:1085 __mmap_region mm/mmap.c:1884 [inline] mmap_region+0x10be/0x18d0 mm/mmap.c:3075 do_mmap+0x801/0xeb0 mm/mmap.c:1661 vm_mmap_pgoff+0x211/0x370 mm/util.c:543 ksys_mmap_pgoff+0x16f/0x1e0 mm/mmap.c:1712 __do_sys_mmap arch/x86/kernel/sys_x86_64.c:95 [inline] __se_sys_mmap arch/x86/kernel/sys_x86_64.c:86 [inline] __x64_sys_mmap+0xfa/0x110 arch/x86/kernel/sys_x86_64.c:86 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb Memory state around the buggy address: ffff88811e852a80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88811e852b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88811e852b80: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc ^ ffff88811e852c00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88811e852c80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 0 PID: 7735 Comm: syz.4.2155 Tainted: G B W syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:update_sit_entry+0x3eb/0xf50 fs/f2fs/segment.c:-1 Code: 89 45 a8 49 01 c5 41 f6 d7 41 80 e7 07 44 89 f9 41 bf 01 00 00 00 41 d3 e7 4d 89 ee 49 c1 ee 03 48 b8 00 00 00 00 00 fc ff df <41> 0f b6 04 06 84 c0 0f 85 a5 08 00 00 41 0f b6 5d 00 44 89 f8 41 RSP: 0018:ffffc90000bd7630 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: ffff88811e852bc8 RCX: 0000000000000007 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff88811e852bc8 RBP: ffffc90000bd76b0 R08: ffff888132d03b40 R09: 0000000000000003 R10: 00000000ffffffff R11: 0000000000000002 R12: 0000000000004000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000080 FS: 00007f4d9b9436c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c2a7ef4 CR3: 000000012f95e000 CR4: 00000000003506b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: f2fs_allocate_data_block+0x159c/0x3a20 fs/f2fs/segment.c:3481 __allocate_data_block+0x553/0x9d0 fs/f2fs/data.c:1413 f2fs_map_blocks+0xda4/0x35a0 fs/f2fs/data.c:1581 expand_inode_data+0x626/0x9a0 fs/f2fs/file.c:1765 f2fs_fallocate+0x42b/0x7e0 fs/f2fs/file.c:1866 vfs_fallocate+0x4b4/0x590 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+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7f4d9cee8819 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f4d9b943028 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 00007f4d9d161fa0 RCX: 00007f4d9cee8819 RDX: 0000000000000bf5 RSI: 0000000000000000 RDI: 0000000000000006 RBP: 00007f4d9cf7ec91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000002000402 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f4d9d162038 R14: 00007f4d9d161fa0 R15: 00007ffdb9d835d8 Modules linked in: ---[ end trace 9b37bca0cd123cab ]--- RIP: 0010:update_sit_entry+0x3eb/0xf50 fs/f2fs/segment.c:-1 Code: 89 45 a8 49 01 c5 41 f6 d7 41 80 e7 07 44 89 f9 41 bf 01 00 00 00 41 d3 e7 4d 89 ee 49 c1 ee 03 48 b8 00 00 00 00 00 fc ff df <41> 0f b6 04 06 84 c0 0f 85 a5 08 00 00 41 0f b6 5d 00 44 89 f8 41 RSP: 0018:ffffc90000bd7630 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: ffff88811e852bc8 RCX: 0000000000000007 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff88811e852bc8 RBP: ffffc90000bd76b0 R08: ffff888132d03b40 R09: 0000000000000003 R10: 00000000ffffffff R11: 0000000000000002 R12: 0000000000004000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000080 FS: 00007f4d9b9436c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055bb4203aaf8 CR3: 000000012f95e000 CR4: 00000000003506a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 89 45 a8 mov %eax,-0x58(%rbp) 3: 49 01 c5 add %rax,%r13 6: 41 f6 d7 not %r15b 9: 41 80 e7 07 and $0x7,%r15b d: 44 89 f9 mov %r15d,%ecx 10: 41 bf 01 00 00 00 mov $0x1,%r15d 16: 41 d3 e7 shl %cl,%r15d 19: 4d 89 ee mov %r13,%r14 1c: 49 c1 ee 03 shr $0x3,%r14 20: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 27: fc ff df * 2a: 41 0f b6 04 06 movzbl (%r14,%rax,1),%eax <-- trapping instruction 2f: 84 c0 test %al,%al 31: 0f 85 a5 08 00 00 jne 0x8dc 37: 41 0f b6 5d 00 movzbl 0x0(%r13),%ebx 3c: 44 89 f8 mov %r15d,%eax 3f: 41 rex.B