Hello, syzbot found the following issue on: HEAD commit: e7c5433c5aaa tools: ynl: Remove duplicated include in hand.. git tree: net-next console+strace: https://syzkaller.appspot.com/x/log.txt?x=109d3d1d280000 kernel config: https://syzkaller.appspot.com/x/.config?x=526f919910d4a671 dashboard link: https://syzkaller.appspot.com/bug?extid=d8486855ef44506fd675 compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=10f22943280000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13e1363b280000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/13c08af1fd21/disk-e7c5433c.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/35820511752b/vmlinux-e7c5433c.xz kernel image: https://storage.googleapis.com/syzbot-assets/6a8cbec0d40f/bzImage-e7c5433c.xz The issue was bisected to: commit 2dc334f1a63a8839b88483a3e73c0f27c9c1791c Author: David Howells <dhowells@xxxxxxxxxx> Date: Wed Jun 7 18:19:09 2023 +0000 splice, net: Use sendmsg(MSG_SPLICE_PAGES) rather than ->sendpage() bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=149e0c8b280000 final oops: https://syzkaller.appspot.com/x/report.txt?x=169e0c8b280000 console output: https://syzkaller.appspot.com/x/log.txt?x=129e0c8b280000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+d8486855ef44506fd675@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: 2dc334f1a63a ("splice, net: Use sendmsg(MSG_SPLICE_PAGES) rather than ->sendpage()") ================================================================== BUG: KASAN: stack-out-of-bounds in skb_splice_from_iter+0xcd6/0xd70 net/core/skbuff.c:6933 Read of size 8 at addr ffffc900039bf8f8 by task syz-executor193/5001 CPU: 1 PID: 5001 Comm: syz-executor193 Not tainted 6.4.0-rc5-syzkaller-00915-ge7c5433c5aaa #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106 print_address_description.constprop.0+0x2c/0x3c0 mm/kasan/report.c:351 print_report mm/kasan/report.c:462 [inline] kasan_report+0x11c/0x130 mm/kasan/report.c:572 skb_splice_from_iter+0xcd6/0xd70 net/core/skbuff.c:6933 __ip_append_data+0x1439/0x3c20 net/ipv4/ip_output.c:1210 ip_append_data net/ipv4/ip_output.c:1350 [inline] ip_append_data+0x115/0x1a0 net/ipv4/ip_output.c:1329 raw_sendmsg+0xb50/0x30a0 net/ipv4/raw.c:641 inet_sendmsg+0x9d/0xe0 net/ipv4/af_inet.c:829 sock_sendmsg_nosec net/socket.c:724 [inline] sock_sendmsg+0xde/0x190 net/socket.c:747 splice_to_socket+0x954/0xe30 fs/splice.c:917 do_splice_from fs/splice.c:969 [inline] do_splice+0xb8c/0x1e50 fs/splice.c:1309 __do_splice+0x14e/0x270 fs/splice.c:1387 __do_sys_splice fs/splice.c:1598 [inline] __se_sys_splice fs/splice.c:1580 [inline] __x64_sys_splice+0x19c/0x250 fs/splice.c:1580 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fba0bf36d29 Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 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 c0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffe0d4bac38 EFLAGS: 00000246 ORIG_RAX: 0000000000000113 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fba0bf36d29 RDX: 0000000000000005 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007fba0befaed0 R08: 000000000004ffdd R09: 000000000000000d R10: 0000000000000000 R11: 0000000000000246 R12: 00007fba0befaf60 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 </TASK> The buggy address belongs to stack of task syz-executor193/5001 and is located at offset 408 in frame: raw_sendmsg+0x0/0x30a0 include/net/sock.h:2733 This frame has 8 objects: [48, 52) 'hdrincl' [64, 68) 'err' [80, 88) 'rt' [112, 152) 'ipc' [192, 240) 'state' [272, 336) 'fl4' [368, 392) 'rfv' [432, 504) 'opt_copy' The buggy address belongs to the virtual mapping at [ffffc900039b8000, ffffc900039c1000) created by: kernel_clone+0xeb/0x890 kernel/fork.c:2915 The buggy address belongs to the physical page: page:ffffea0001d6c880 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x75b22 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000000000 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 0x2dc2(GFP_KERNEL|__GFP_HIGHMEM|__GFP_NOWARN|__GFP_ZERO), pid 4968, tgid 4968 (dhcpcd-run-hook), ts 47435778840, free_ts 47434086594 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2db/0x350 mm/page_alloc.c:1731 prep_new_page mm/page_alloc.c:1738 [inline] get_page_from_freelist+0xf41/0x2c00 mm/page_alloc.c:3502 __alloc_pages+0x1cb/0x4a0 mm/page_alloc.c:4768 alloc_pages+0x1aa/0x270 mm/mempolicy.c:2279 vm_area_alloc_pages mm/vmalloc.c:3009 [inline] __vmalloc_area_node mm/vmalloc.c:3085 [inline] __vmalloc_node_range+0xb1c/0x14a0 mm/vmalloc.c:3257 alloc_thread_stack_node kernel/fork.c:313 [inline] dup_task_struct kernel/fork.c:1116 [inline] copy_process+0x13bb/0x75c0 kernel/fork.c:2333 kernel_clone+0xeb/0x890 kernel/fork.c:2915 __do_sys_clone+0xba/0x100 kernel/fork.c:3058 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1302 [inline] free_unref_page_prepare+0x62e/0xcb0 mm/page_alloc.c:2564 free_unref_page_list+0xe3/0xa70 mm/page_alloc.c:2705 release_pages+0xcd8/0x1380 mm/swap.c:1042 tlb_batch_pages_flush+0xa8/0x1a0 mm/mmu_gather.c:97 tlb_flush_mmu_free mm/mmu_gather.c:292 [inline] tlb_flush_mmu mm/mmu_gather.c:299 [inline] tlb_finish_mmu+0x14b/0x7e0 mm/mmu_gather.c:391 exit_mmap+0x2b2/0x930 mm/mmap.c:3123 __mmput+0x128/0x4c0 kernel/fork.c:1351 mmput+0x60/0x70 kernel/fork.c:1373 exit_mm kernel/exit.c:567 [inline] do_exit+0x9b0/0x29b0 kernel/exit.c:861 do_group_exit+0xd4/0x2a0 kernel/exit.c:1024 __do_sys_exit_group kernel/exit.c:1035 [inline] __se_sys_exit_group kernel/exit.c:1033 [inline] __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1033 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Memory state around the buggy address: ffffc900039bf780: f1 f1 04 f2 00 00 00 f2 f2 f2 00 00 00 00 00 f2 ffffc900039bf800: f2 f2 f2 f2 00 00 00 00 00 00 f2 f2 f2 f2 00 00 >ffffc900039bf880: 00 00 00 00 00 00 f2 f2 f2 f2 00 00 00 f2 f2 f2 ^ ffffc900039bf900: f2 f2 00 00 00 00 00 00 00 00 00 f3 f3 f3 f3 f3 ffffc900039bf980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. For information about bisection process see: https://goo.gl/tpsmEJ#bisection If the bug is already fixed, let syzbot know by replying with: #syz fix: exact-commit-title If you want syzbot to run the reproducer, reply with: #syz test: git://repo/address.git branch-or-commit-hash If you attach or paste a git patch, syzbot will apply it before testing. If you want to change bug's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the bug is a duplicate of another bug, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup
