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KASAN: invalid-free in skb_free_head (2)

Status: fixed on 2023/06/08 14:41
Subsystems: net
[Documentation on labels]
Fix commit: 880ce5f20033 net: avoid skb end_offset change in __skb_unclone_keeptruesize()
First crash: 481d, last: 416d
Cause bisection: failed (error log, bisect log)
  
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: invalid-free in skb_free_head bluetooth C done 1 1690d 1690d 15/27 fixed on 2019/12/13 00:31

Sample crash report:
==================================================================
BUG: KASAN: invalid-free in slab_free mm/slub.c:3787 [inline]
BUG: KASAN: invalid-free in kmem_cache_free+0xee/0x5c0 mm/slub.c:3809
Free of addr ffff88806cdee800 by task syz-executor239/5189

CPU: 0 PID: 5189 Comm: syz-executor239 Not tainted 6.2.0-rc8-syzkaller-02400-gd1fabc68f8e0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:306 [inline]
 print_report+0x15e/0x45d mm/kasan/report.c:417
 kasan_report_invalid_free+0x9b/0x1b0 mm/kasan/report.c:482
 ____kasan_slab_free+0x1a5/0x1c0 mm/kasan/common.c:216
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1781 [inline]
 slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1807
 slab_free mm/slub.c:3787 [inline]
 kmem_cache_free+0xee/0x5c0 mm/slub.c:3809
 skb_kfree_head net/core/skbuff.c:857 [inline]
 skb_kfree_head net/core/skbuff.c:853 [inline]
 skb_free_head+0x16f/0x1a0 net/core/skbuff.c:872
 skb_release_data+0x57a/0x820 net/core/skbuff.c:901
 skb_release_all net/core/skbuff.c:966 [inline]
 __kfree_skb+0x4f/0x70 net/core/skbuff.c:980
 tcp_wmem_free_skb include/net/tcp.h:302 [inline]
 tcp_rtx_queue_purge net/ipv4/tcp.c:3061 [inline]
 tcp_write_queue_purge+0x617/0xcf0 net/ipv4/tcp.c:3074
 tcp_v4_destroy_sock+0x125/0x810 net/ipv4/tcp_ipv4.c:2302
 inet_csk_destroy_sock+0x19a/0x440 net/ipv4/inet_connection_sock.c:1195
 __tcp_close+0xb96/0xf50 net/ipv4/tcp.c:3021
 tcp_close+0x2d/0xc0 net/ipv4/tcp.c:3033
 inet_release+0x132/0x270 net/ipv4/af_inet.c:426
 __sock_release+0xcd/0x280 net/socket.c:651
 sock_close+0x1c/0x20 net/socket.c:1393
 __fput+0x27c/0xa90 fs/file_table.c:320
 task_work_run+0x16f/0x270 kernel/task_work.c:179
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0x23c/0x250 kernel/entry/common.c:203
 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline]
 syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:296
 do_syscall_64+0x46/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f2511f546c3
Code: c7 c2 c0 ff ff ff f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 64 8b 04 25 18 00 00 00 85 c0 75 14 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8
RSP: 002b:00007ffef0103d48 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000004 RCX: 00007f2511f546c3
RDX: 0000000000000978 RSI: 00000000200000c0 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000002 R09: 0000000000003434
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffef0103d6c
R13: 00007ffef0103d80 R14: 00007ffef0103dc0 R15: 0000000000000003
 </TASK>

Allocated by task 5189:
 kasan_save_stack+0x22/0x40 mm/kasan/common.c:45
 kasan_set_track+0x25/0x30 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:374 [inline]
 ____kasan_kmalloc mm/kasan/common.c:333 [inline]
 __kasan_kmalloc+0xa5/0xb0 mm/kasan/common.c:383
 kasan_kmalloc include/linux/kasan.h:211 [inline]
 __do_kmalloc_node mm/slab_common.c:968 [inline]
 __kmalloc_node_track_caller+0x5b/0xc0 mm/slab_common.c:988
 kmalloc_reserve+0xf1/0x230 net/core/skbuff.c:539
 pskb_expand_head+0x237/0x1160 net/core/skbuff.c:1995
 __skb_unclone_keeptruesize+0x93/0x220 net/core/skbuff.c:2094
 skb_unclone_keeptruesize include/linux/skbuff.h:1910 [inline]
 skb_prepare_for_shift net/core/skbuff.c:3804 [inline]
 skb_shift+0xef8/0x1e20 net/core/skbuff.c:3877
 tcp_skb_shift net/ipv4/tcp_input.c:1538 [inline]
 tcp_shift_skb_data net/ipv4/tcp_input.c:1646 [inline]
 tcp_sacktag_walk+0x93b/0x18a0 net/ipv4/tcp_input.c:1713
 tcp_sacktag_write_queue+0x1599/0x31d0 net/ipv4/tcp_input.c:1974
 tcp_ack+0x2e9f/0x5a10 net/ipv4/tcp_input.c:3847
 tcp_rcv_established+0x667/0x2230 net/ipv4/tcp_input.c:6006
 tcp_v4_do_rcv+0x670/0x9b0 net/ipv4/tcp_ipv4.c:1721
 sk_backlog_rcv include/net/sock.h:1113 [inline]
 __release_sock+0x133/0x3b0 net/core/sock.c:2921
 release_sock+0x58/0x1b0 net/core/sock.c:3488
 tcp_sendmsg+0x3a/0x50 net/ipv4/tcp.c:1485
 inet_sendmsg+0x9d/0xe0 net/ipv4/af_inet.c:825
 sock_sendmsg_nosec net/socket.c:722 [inline]
 sock_sendmsg+0xde/0x190 net/socket.c:745
 sock_write_iter+0x295/0x3d0 net/socket.c:1136
 call_write_iter include/linux/fs.h:2189 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x9ed/0xdd0 fs/read_write.c:584
 ksys_write+0x1ec/0x250 fs/read_write.c:637
 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

The buggy address belongs to the object at ffff88806cdee800
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 0 bytes inside of
 1024-byte region [ffff88806cdee800, ffff88806cdeec00)

The buggy address belongs to the physical page:
page:ffffea0001b37a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x6cde8
head:ffffea0001b37a00 order:3 compound_mapcount:0 subpages_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffff888012441dc0 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000100010 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 0x1f2a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_MEMALLOC|__GFP_HARDWALL), pid 75, tgid 75 (kworker/u4:4), ts 96369578780, free_ts 26734162530
 prep_new_page mm/page_alloc.c:2531 [inline]
 get_page_from_freelist+0x119c/0x2ce0 mm/page_alloc.c:4283
 __alloc_pages+0x1cb/0x5b0 mm/page_alloc.c:5549
 alloc_pages+0x1aa/0x270 mm/mempolicy.c:2287
 alloc_slab_page mm/slub.c:1851 [inline]
 allocate_slab+0x25f/0x350 mm/slub.c:1998
 new_slab mm/slub.c:2051 [inline]
 ___slab_alloc+0xa91/0x1400 mm/slub.c:3193
 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3292
 __slab_alloc_node mm/slub.c:3345 [inline]
 slab_alloc_node mm/slub.c:3442 [inline]
 __kmem_cache_alloc_node+0x1a4/0x430 mm/slub.c:3491
 __do_kmalloc_node mm/slab_common.c:967 [inline]
 __kmalloc_node_track_caller+0x4b/0xc0 mm/slab_common.c:988
 kmalloc_reserve+0xf1/0x230 net/core/skbuff.c:539
 __alloc_skb+0x129/0x330 net/core/skbuff.c:608
 __netdev_alloc_skb+0x74/0x410 net/core/skbuff.c:672
 __netdev_alloc_skb_ip_align include/linux/skbuff.h:3203 [inline]
 netdev_alloc_skb_ip_align include/linux/skbuff.h:3213 [inline]
 batadv_iv_ogm_aggregate_new+0x106/0x4e0 net/batman-adv/bat_iv_ogm.c:558
 batadv_iv_ogm_queue_add net/batman-adv/bat_iv_ogm.c:670 [inline]
 batadv_iv_ogm_schedule_buff+0xe6b/0x1450 net/batman-adv/bat_iv_ogm.c:849
 batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:868 [inline]
 batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:861 [inline]
 batadv_iv_send_outstanding_bat_ogm_packet+0x744/0x910 net/batman-adv/bat_iv_ogm.c:1712
 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289
 worker_thread+0x669/0x1090 kernel/workqueue.c:2436
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1446 [inline]
 free_pcp_prepare+0x66a/0xc20 mm/page_alloc.c:1496
 free_unref_page_prepare mm/page_alloc.c:3369 [inline]
 free_unref_page+0x1d/0x490 mm/page_alloc.c:3464
 free_contig_range+0xb5/0x180 mm/page_alloc.c:9488
 destroy_args+0xa8/0x64c mm/debug_vm_pgtable.c:998
 debug_vm_pgtable+0x28de/0x296f mm/debug_vm_pgtable.c:1318
 do_one_initcall+0x141/0x790 init/main.c:1306
 do_initcall_level init/main.c:1379 [inline]
 do_initcalls init/main.c:1395 [inline]
 do_basic_setup init/main.c:1414 [inline]
 kernel_init_freeable+0x6f9/0x782 init/main.c:1634
 kernel_init+0x1e/0x1d0 init/main.c:1522
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308

Memory state around the buggy address:
 ffff88806cdee700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88806cdee780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88806cdee800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                   ^
 ffff88806cdee880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88806cdee900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================

Crashes (25):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/02/22 02:45 net-next-old d1fabc68f8e0 42a4d508 .config console log report syz C ci-upstream-net-kasan-gce KASAN: invalid-free in skb_free_head
2023/03/06 08:50 upstream f915322fe014 f8902b57 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root KASAN: invalid-free in skb_free_head
2023/03/03 17:56 upstream 2eb29d59ddf0 f8902b57 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root KASAN: invalid-free in skb_free_head
2023/03/03 17:46 upstream 2eb29d59ddf0 f8902b57 .config console log report info ci-upstream-kasan-gce KASAN: invalid-free in skb_free_head
2023/03/01 17:13 upstream c0927a7a5391 f8902b57 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root KASAN: invalid-free in skb_free_head
2023/03/01 15:03 upstream c0927a7a5391 f8902b57 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce KASAN: invalid-free in skb_free_head
2023/02/22 20:20 upstream 5b7c4cabbb65 409945bc .config console log report info ci-upstream-kasan-gce KASAN: invalid-free in skb_free_head
2023/03/01 07:23 net-old 724337be7f21 95aee97a .config console log report info ci-upstream-net-this-kasan-gce KASAN: invalid-free in skb_free_head
2023/04/28 05:05 net-next 6e98b09da931 70a605de .config console log report info ci-upstream-net-kasan-gce KASAN: invalid-free in skb_free_head
2023/03/09 15:14 net-next ed69e0667db5 f08b59ac .config console log report info ci-upstream-net-kasan-gce KASAN: invalid-free in skb_free_head
2023/03/08 15:24 net-next 0194b64578e9 d2b00170 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce KASAN: invalid-free in skb_free_head
2023/02/22 02:14 net-next-old d1fabc68f8e0 42a4d508 .config console log report info ci-upstream-net-kasan-gce KASAN: invalid-free in skb_free_head
2023/03/24 10:38 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci fe15c26ee26e f94b4a29 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: invalid-free in skb_free_head
2023/03/23 12:31 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci fe15c26ee26e f94b4a29 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: invalid-free in skb_free_head
2023/03/23 03:43 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci fe15c26ee26e f94b4a29 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: invalid-free in skb_free_head
2023/03/22 09:25 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci fe15c26ee26e 8b4eb097 .config console log report info ci-upstream-gce-arm64 KASAN: invalid-free in skb_free_head
2023/03/22 07:12 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci fe15c26ee26e 8b4eb097 .config console log report info ci-upstream-gce-arm64 KASAN: invalid-free in skb_free_head
2023/03/22 05:10 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci fe15c26ee26e 8b4eb097 .config console log report info ci-upstream-gce-arm64 KASAN: invalid-free in skb_free_head
2023/03/21 18:04 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci fe15c26ee26e 03fb9538 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: invalid-free in skb_free_head
2023/03/15 11:12 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci fe15c26ee26e 0d5c4377 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: invalid-free in skb_free_head
2023/03/15 08:17 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci fe15c26ee26e 0d5c4377 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: invalid-free in skb_free_head
2023/03/14 18:40 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci fe15c26ee26e 0d5c4377 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: invalid-free in skb_free_head
2023/03/14 17:51 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci fe15c26ee26e 0d5c4377 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: invalid-free in skb_free_head
2023/03/10 12:12 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci fe15c26ee26e 5205ef30 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: invalid-free in skb_free_head
2023/03/09 14:46 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci fe15c26ee26e f08b59ac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: invalid-free in skb_free_head
* Struck through repros no longer work on HEAD.