Hello,
syzbot found the following issue on:
HEAD commit: 2506f6229bd0 Merge branch 'net-dsa-adjust_link-removal'
git tree: net-next
console output: https://syzkaller.appspot.com/x/log.txt?x=11ac64ef180000
kernel config: https://syzkaller.appspot.com/x/.config?x=15dda165e1d20cf1
dashboard link: https://syzkaller.appspot.com/bug?extid=061f58eec3bde7ee8ffa
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/fc61e6a6e169/disk-2506f622.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/3ed6cc1ccbe5/vmlinux-2506f622.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c6ea42464245/bzImage-2506f622.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email protected]
==================================================================
BUG: KASAN: slab-use-after-free in lockdep_register_key+0x253/0x3f0 kernel/locking/lockdep.c:1225
Read of size 8 at addr ffff88805fe2c298 by task syz-executor.1/5906
CPU: 1 PID: 5906 Comm: syz-executor.1 Not tainted 6.9.0-rc5-syzkaller-01473-g2506f6229bd0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
print_address_description mm/kasan/report.c:377 [inline]
print_report+0x169/0x550 mm/kasan/report.c:488
kasan_report+0x143/0x180 mm/kasan/report.c:601
lockdep_register_key+0x253/0x3f0 kernel/locking/lockdep.c:1225
htab_map_alloc+0x9b/0xe60 kernel/bpf/hashtab.c:506
map_create+0x90c/0x1200 kernel/bpf/syscall.c:1333
__sys_bpf+0x6d1/0x810 kernel/bpf/syscall.c:5659
__do_sys_bpf kernel/bpf/syscall.c:5784 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5782 [inline]
__x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5782
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7781e7dea9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7782c720c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f7781fabf80 RCX: 00007f7781e7dea9
RDX: 0000000000000048 RSI: 0000000020000140 RDI: 0100000000000000
RBP: 00007f7781eca4a4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f7781fabf80 R15: 00007ffe14057dd8
</TASK>
Allocated by task 5593:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:370 [inline]
__kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:387
kasan_kmalloc include/linux/kasan.h:211 [inline]
__do_kmalloc_node mm/slub.c:3966 [inline]
__kmalloc_node_track_caller+0x24e/0x4e0 mm/slub.c:3986
kmalloc_reserve+0x111/0x2a0 net/core/skbuff.c:597
__alloc_skb+0x1f3/0x440 net/core/skbuff.c:666
alloc_skb include/linux/skbuff.h:1308 [inline]
alloc_skb_with_frags+0xc3/0x770 net/core/skbuff.c:6455
sock_alloc_send_pskb+0x91a/0xa60 net/core/sock.c:2794
sock_alloc_send_skb include/net/sock.h:1766 [inline]
llc_ui_sendmsg+0x48d/0xf80 net/llc/af_llc.c:971
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0x221/0x270 net/socket.c:745
sock_sendmsg+0x134/0x200 net/socket.c:768
splice_to_socket+0xa13/0x10b0 fs/splice.c:889
do_splice_from fs/splice.c:941 [inline]
direct_splice_actor+0x11e/0x220 fs/splice.c:1164
splice_direct_to_actor+0x58e/0xc90 fs/splice.c:1108
do_splice_direct_actor fs/splice.c:1207 [inline]
do_splice_direct+0x28c/0x3e0 fs/splice.c:1233
do_sendfile+0x56d/0xdc0 fs/read_write.c:1295
__do_sys_sendfile64 fs/read_write.c:1362 [inline]
__se_sys_sendfile64+0x17c/0x1e0 fs/read_write.c:1348
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 5593:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579
poison_slab_object+0xa6/0xe0 mm/kasan/common.c:240
__kasan_slab_free+0x37/0x60 mm/kasan/common.c:256
kasan_slab_free include/linux/kasan.h:184 [inline]
slab_free_hook mm/slub.c:2106 [inline]
slab_free mm/slub.c:4280 [inline]
kfree+0x153/0x3a0 mm/slub.c:4390
skb_kfree_head net/core/skbuff.c:1033 [inline]
skb_free_head net/core/skbuff.c:1045 [inline]
skb_release_data+0x676/0x880 net/core/skbuff.c:1072
skb_release_all net/core/skbuff.c:1137 [inline]
__kfree_skb net/core/skbuff.c:1151 [inline]
kfree_skb_reason+0x1a3/0x3b0 net/core/skbuff.c:1187
llc_ui_sendmsg+0xb03/0xf80 net/llc/af_llc.c:1000
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0x221/0x270 net/socket.c:745
sock_sendmsg+0x134/0x200 net/socket.c:768
splice_to_socket+0xa13/0x10b0 fs/splice.c:889
do_splice_from fs/splice.c:941 [inline]
direct_splice_actor+0x11e/0x220 fs/splice.c:1164
splice_direct_to_actor+0x58e/0xc90 fs/splice.c:1108
do_splice_direct_actor fs/splice.c:1207 [inline]
do_splice_direct+0x28c/0x3e0 fs/splice.c:1233
do_sendfile+0x56d/0xdc0 fs/read_write.c:1295
__do_sys_sendfile64 fs/read_write.c:1362 [inline]
__se_sys_sendfile64+0x17c/0x1e0 fs/read_write.c:1348
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff88805fe2c000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 664 bytes inside of
freed 2048-byte region [ffff88805fe2c000, ffff88805fe2c800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5fe28
head: order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff80000000840(slab|head|node=0|zone=1|lastcpupid=0xfff)
page_type: 0xffffffff()
raw: 00fff80000000840 ffff888015042000 dead000000000100 dead000000000122
raw: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000
head: 00fff80000000840 ffff888015042000 dead000000000100 dead000000000122
head: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000
head: 00fff80000000003 ffffea00017f8a01 dead000000000122 00000000ffffffff
head: 0000000800000000 0000000000000000 00000000ffffffff 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5095, tgid 21395662 (syz-executor.0), ts 5095, free_ts 13812911031
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x1ea/0x210 mm/page_alloc.c:1534
prep_new_page mm/page_alloc.c:1541 [inline]
get_page_from_freelist+0x3410/0x35b0 mm/page_alloc.c:3317
__alloc_pages+0x256/0x6c0 mm/page_alloc.c:4575
__alloc_pages_node include/linux/gfp.h:238 [inline]
alloc_pages_node include/linux/gfp.h:261 [inline]
alloc_slab_page+0x5f/0x160 mm/slub.c:2175
allocate_slab mm/slub.c:2338 [inline]
new_slab+0x84/0x2f0 mm/slub.c:2391
___slab_alloc+0xc73/0x1260 mm/slub.c:3525
__slab_alloc mm/slub.c:3610 [inline]
__slab_alloc_node mm/slub.c:3663 [inline]
slab_alloc_node mm/slub.c:3835 [inline]
kmalloc_trace+0x269/0x360 mm/slub.c:3992
kmalloc include/linux/slab.h:628 [inline]
rtnl_newlink+0xf2/0x20a0 net/core/rtnetlink.c:3723
rtnetlink_rcv_msg+0x89b/0x10d0 net/core/rtnetlink.c:6594
netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2564
netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline]
netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361
netlink_sendmsg+0x8e1/0xcb0 net/netlink/af_netlink.c:1905
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0x221/0x270 net/socket.c:745
__sys_sendto+0x3a4/0x4f0 net/socket.c:2191
__do_sys_sendto net/socket.c:2203 [inline]
__se_sys_sendto net/socket.c:2199 [inline]
__x64_sys_sendto+0xde/0x100 net/socket.c:2199
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
page last free pid 1 tgid 1 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1141 [inline]
free_unref_page_prepare+0x986/0xab0 mm/page_alloc.c:2347
free_unref_page+0x37/0x3f0 mm/page_alloc.c:2487
free_contig_range+0x9e/0x160 mm/page_alloc.c:6572
destroy_args+0x8a/0x890 mm/debug_vm_pgtable.c:1036
debug_vm_pgtable+0x4be/0x550 mm/debug_vm_pgtable.c:1416
do_one_initcall+0x248/0x880 init/main.c:1245
do_initcall_level+0x157/0x210 init/main.c:1307
do_initcalls+0x3f/0x80 init/main.c:1323
kernel_init_freeable+0x435/0x5d0 init/main.c:1555
kernel_init+0x1d/0x2b0 init/main.c:1444
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff88805fe2c180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88805fe2c200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88805fe2c280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88805fe2c300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88805fe2c380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
---
This report is generated by a bot. It may contain errors.
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#syz undup
Hi,
On 5/4/2024 6:21 PM, syzbot wrote:
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit: 2506f6229bd0 Merge branch 'net-dsa-adjust_link-removal'
> git tree: net-next
> console output: https://syzkaller.appspot.com/x/log.txt?x=11ac64ef180000
> kernel config: https://syzkaller.appspot.com/x/.config?x=15dda165e1d20cf1
> dashboard link: https://syzkaller.appspot.com/bug?extid=061f58eec3bde7ee8ffa
> compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
>
> Unfortunately, I don't have any reproducer for this issue yet.
>
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/fc61e6a6e169/disk-2506f622.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/3ed6cc1ccbe5/vmlinux-2506f622.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/c6ea42464245/bzImage-2506f622.xz
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: [email protected]
>
> ==================================================================
> BUG: KASAN: slab-use-after-free in lockdep_register_key+0x253/0x3f0 kernel/locking/lockdep.c:1225
> Read of size 8 at addr ffff88805fe2c298 by task syz-executor.1/5906
>
> CPU: 1 PID: 5906 Comm: syz-executor.1 Not tainted 6.9.0-rc5-syzkaller-01473-g2506f6229bd0 #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
> Call Trace:
> <TASK>
> __dump_stack lib/dump_stack.c:88 [inline]
> dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
> print_address_description mm/kasan/report.c:377 [inline]
> print_report+0x169/0x550 mm/kasan/report.c:488
> kasan_report+0x143/0x180 mm/kasan/report.c:601
> lockdep_register_key+0x253/0x3f0 kernel/locking/lockdep.c:1225
> htab_map_alloc+0x9b/0xe60 kernel/bpf/hashtab.c:506
> map_create+0x90c/0x1200 kernel/bpf/syscall.c:1333
> __sys_bpf+0x6d1/0x810 kernel/bpf/syscall.c:5659
> __do_sys_bpf kernel/bpf/syscall.c:5784 [inline]
> __se_sys_bpf kernel/bpf/syscall.c:5782 [inline]
> __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5782
> do_syscall_x64 arch/x86/entry/common.c:52 [inline]
> do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
> entry_SYSCALL_64_after_hwframe+0x77/0x7f
> RIP: 0033:0x7f7781e7dea9
> Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48
> RSP: 002b:00007f7782c720c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
> RAX: ffffffffffffffda RBX: 00007f7781fabf80 RCX: 00007f7781e7dea9
> RDX: 0000000000000048 RSI: 0000000020000140 RDI: 0100000000000000
> RBP: 00007f7781eca4a4 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
> R13: 000000000000000b R14: 00007f7781fabf80 R15: 00007ffe14057dd8
> </TASK>
>
> Allocated by task 5593:
> kasan_save_stack mm/kasan/common.c:47 [inline]
> kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
> poison_kmalloc_redzone mm/kasan/common.c:370 [inline]
> __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:387
> kasan_kmalloc include/linux/kasan.h:211 [inline]
> __do_kmalloc_node mm/slub.c:3966 [inline]
> __kmalloc_node_track_caller+0x24e/0x4e0 mm/slub.c:3986
> kmalloc_reserve+0x111/0x2a0 net/core/skbuff.c:597
> __alloc_skb+0x1f3/0x440 net/core/skbuff.c:666
> alloc_skb include/linux/skbuff.h:1308 [inline]
SNIP
>
> The buggy address belongs to the object at ffff88805fe2c000
> which belongs to the cache kmalloc-2k of size 2048
> The buggy address is located 664 bytes inside of
> freed 2048-byte region [ffff88805fe2c000, ffff88805fe2c800)
After checking all possible callers of lockdep_register_key(), it seems
that the culprit is Qdisc instead of bpf hash-table, because only the
offset of lock_class_key in Qdisc is 664. And I think the use-after-free
problem happens as follow:
(1) call qdisc_alloc()
After calling lockdep_register_key(), qdisc_alloc() goes to errout1 due
to netdev_alloc_pcpu_stats() fails. However it doesn't call
lockdep_register_key() to unregister root_lock_key, but it frees the
allocated memory
(2) call htab_map_alloc
During the calling of lockdep_register_key(), it finds the lockdep_key
registered by free-ed Qdisc and triggers the use-after-free.
Will post a simple patch to fix it.
On 5/4/2024 6:21 PM, syzbot wrote:
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit: 2506f6229bd0 Merge branch 'net-dsa-adjust_link-removal'
> git tree: net-next
> console output: https://syzkaller.appspot.com/x/log.txt?x=11ac64ef180000
> kernel config: https://syzkaller.appspot.com/x/.config?x=15dda165e1d20cf1
> dashboard link: https://syzkaller.appspot.com/bug?extid=061f58eec3bde7ee8ffa
> compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
>
> Unfortunately, I don't have any reproducer for this issue yet.
>
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/fc61e6a6e169/disk-2506f622.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/3ed6cc1ccbe5/vmlinux-2506f622.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/c6ea42464245/bzImage-2506f622.xz
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: [email protected]
>
> ==================================================================
> BUG: KASAN: slab-use-after-free in lockdep_register_key+0x253/0x3f0 kernel/locking/lockdep.c:1225
> Read of size 8 at addr ffff88805fe2c298 by task syz-executor.1/5906
>
> CPU: 1 PID: 5906 Comm: syz-executor.1 Not tainted 6.9.0-rc5-syzkaller-01473-g2506f6229bd0 #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
> Call Trace:
> <TASK>
> __dump_stack lib/dump_stack.c:88 [inline]
> dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
> print_address_description mm/kasan/report.c:377 [inline]
> print_report+0x169/0x550 mm/kasan/report.c:488
> kasan_report+0x143/0x180 mm/kasan/report.c:601
> lockdep_register_key+0x253/0x3f0 kernel/locking/lockdep.c:1225
> htab_map_alloc+0x9b/0xe60 kernel/bpf/hashtab.c:506
> map_create+0x90c/0x1200 kernel/bpf/syscall.c:1333
> __sys_bpf+0x6d1/0x810 kernel/bpf/syscall.c:5659
> __do_sys_bpf kernel/bpf/syscall.c:5784 [inline]
> __se_sys_bpf kernel/bpf/syscall.c:5782 [inline]
> __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5782
> do_syscall_x64 arch/x86/entry/common.c:52 [inline]
> do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
> entry_SYSCALL_64_after_hwframe+0x77/0x7f
> RIP: 0033:0x7f7781e7dea9
> Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48
> RSP: 002b:00007f7782c720c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
> RAX: ffffffffffffffda RBX: 00007f7781fabf80 RCX: 00007f7781e7dea9
> RDX: 0000000000000048 RSI: 0000000020000140 RDI: 0100000000000000
> RBP: 00007f7781eca4a4 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
> R13: 000000000000000b R14: 00007f7781fabf80 R15: 00007ffe14057dd8
> </TASK>
>
> Allocated by task 5593:
> kasan_save_stack mm/kasan/common.c:47 [inline]
> kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
> poison_kmalloc_redzone mm/kasan/common.c:370 [inline]
> __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:387
> kasan_kmalloc include/linux/kasan.h:211 [inline]
> __do_kmalloc_node mm/slub.c:3966 [inline]
> __kmalloc_node_track_caller+0x24e/0x4e0 mm/slub.c:3986
> kmalloc_reserve+0x111/0x2a0 net/core/skbuff.c:597
> __alloc_skb+0x1f3/0x440 net/core/skbuff.c:666
> alloc_skb include/linux/skbuff.h:1308 [inline]
> alloc_skb_with_frags+0xc3/0x770 net/core/skbuff.c:6455
> sock_alloc_send_pskb+0x91a/0xa60 net/core/sock.c:2794
> sock_alloc_send_skb include/net/sock.h:1766 [inline]
> llc_ui_sendmsg+0x48d/0xf80 net/llc/af_llc.c:971
> sock_sendmsg_nosec net/socket.c:730 [inline]
> __sock_sendmsg+0x221/0x270 net/socket.c:745
> sock_sendmsg+0x134/0x200 net/socket.c:768
> splice_to_socket+0xa13/0x10b0 fs/splice.c:889
> do_splice_from fs/splice.c:941 [inline]
> direct_splice_actor+0x11e/0x220 fs/splice.c:1164
> splice_direct_to_actor+0x58e/0xc90 fs/splice.c:1108
> do_splice_direct_actor fs/splice.c:1207 [inline]
> do_splice_direct+0x28c/0x3e0 fs/splice.c:1233
> do_sendfile+0x56d/0xdc0 fs/read_write.c:1295
> __do_sys_sendfile64 fs/read_write.c:1362 [inline]
> __se_sys_sendfile64+0x17c/0x1e0 fs/read_write.c:1348
> do_syscall_x64 arch/x86/entry/common.c:52 [inline]
> do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
> entry_SYSCALL_64_after_hwframe+0x77/0x7f
>
> Freed by task 5593:
> kasan_save_stack mm/kasan/common.c:47 [inline]
> kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
> kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579
> poison_slab_object+0xa6/0xe0 mm/kasan/common.c:240
> __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256
> kasan_slab_free include/linux/kasan.h:184 [inline]
> slab_free_hook mm/slub.c:2106 [inline]
> slab_free mm/slub.c:4280 [inline]
> kfree+0x153/0x3a0 mm/slub.c:4390
> skb_kfree_head net/core/skbuff.c:1033 [inline]
> skb_free_head net/core/skbuff.c:1045 [inline]
> skb_release_data+0x676/0x880 net/core/skbuff.c:1072
> skb_release_all net/core/skbuff.c:1137 [inline]
> __kfree_skb net/core/skbuff.c:1151 [inline]
> kfree_skb_reason+0x1a3/0x3b0 net/core/skbuff.c:1187
> llc_ui_sendmsg+0xb03/0xf80 net/llc/af_llc.c:1000
> sock_sendmsg_nosec net/socket.c:730 [inline]
> __sock_sendmsg+0x221/0x270 net/socket.c:745
> sock_sendmsg+0x134/0x200 net/socket.c:768
> splice_to_socket+0xa13/0x10b0 fs/splice.c:889
> do_splice_from fs/splice.c:941 [inline]
> direct_splice_actor+0x11e/0x220 fs/splice.c:1164
> splice_direct_to_actor+0x58e/0xc90 fs/splice.c:1108
> do_splice_direct_actor fs/splice.c:1207 [inline]
> do_splice_direct+0x28c/0x3e0 fs/splice.c:1233
> do_sendfile+0x56d/0xdc0 fs/read_write.c:1295
> __do_sys_sendfile64 fs/read_write.c:1362 [inline]
> __se_sys_sendfile64+0x17c/0x1e0 fs/read_write.c:1348
> do_syscall_x64 arch/x86/entry/common.c:52 [inline]
> do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
> entry_SYSCALL_64_after_hwframe+0x77/0x7f
>
> The buggy address belongs to the object at ffff88805fe2c000
> which belongs to the cache kmalloc-2k of size 2048
> The buggy address is located 664 bytes inside of
> freed 2048-byte region [ffff88805fe2c000, ffff88805fe2c800)
>
> The buggy address belongs to the physical page:
> page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5fe28
> head: order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
> flags: 0xfff80000000840(slab|head|node=0|zone=1|lastcpupid=0xfff)
> page_type: 0xffffffff()
> raw: 00fff80000000840 ffff888015042000 dead000000000100 dead000000000122
> raw: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000
> head: 00fff80000000840 ffff888015042000 dead000000000100 dead000000000122
> head: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000
> head: 00fff80000000003 ffffea00017f8a01 dead000000000122 00000000ffffffff
> head: 0000000800000000 0000000000000000 00000000ffffffff 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5095, tgid 21395662 (syz-executor.0), ts 5095, free_ts 13812911031
> set_page_owner include/linux/page_owner.h:32 [inline]
> post_alloc_hook+0x1ea/0x210 mm/page_alloc.c:1534
> prep_new_page mm/page_alloc.c:1541 [inline]
> get_page_from_freelist+0x3410/0x35b0 mm/page_alloc.c:3317
> __alloc_pages+0x256/0x6c0 mm/page_alloc.c:4575
> __alloc_pages_node include/linux/gfp.h:238 [inline]
> alloc_pages_node include/linux/gfp.h:261 [inline]
> alloc_slab_page+0x5f/0x160 mm/slub.c:2175
> allocate_slab mm/slub.c:2338 [inline]
> new_slab+0x84/0x2f0 mm/slub.c:2391
> ___slab_alloc+0xc73/0x1260 mm/slub.c:3525
> __slab_alloc mm/slub.c:3610 [inline]
> __slab_alloc_node mm/slub.c:3663 [inline]
> slab_alloc_node mm/slub.c:3835 [inline]
> kmalloc_trace+0x269/0x360 mm/slub.c:3992
> kmalloc include/linux/slab.h:628 [inline]
> rtnl_newlink+0xf2/0x20a0 net/core/rtnetlink.c:3723
> rtnetlink_rcv_msg+0x89b/0x10d0 net/core/rtnetlink.c:6594
> netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2564
> netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline]
> netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361
> netlink_sendmsg+0x8e1/0xcb0 net/netlink/af_netlink.c:1905
> sock_sendmsg_nosec net/socket.c:730 [inline]
> __sock_sendmsg+0x221/0x270 net/socket.c:745
> __sys_sendto+0x3a4/0x4f0 net/socket.c:2191
> __do_sys_sendto net/socket.c:2203 [inline]
> __se_sys_sendto net/socket.c:2199 [inline]
> __x64_sys_sendto+0xde/0x100 net/socket.c:2199
> do_syscall_x64 arch/x86/entry/common.c:52 [inline]
> do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
> page last free pid 1 tgid 1 stack trace:
> reset_page_owner include/linux/page_owner.h:25 [inline]
> free_pages_prepare mm/page_alloc.c:1141 [inline]
> free_unref_page_prepare+0x986/0xab0 mm/page_alloc.c:2347
> free_unref_page+0x37/0x3f0 mm/page_alloc.c:2487
> free_contig_range+0x9e/0x160 mm/page_alloc.c:6572
> destroy_args+0x8a/0x890 mm/debug_vm_pgtable.c:1036
> debug_vm_pgtable+0x4be/0x550 mm/debug_vm_pgtable.c:1416
> do_one_initcall+0x248/0x880 init/main.c:1245
> do_initcall_level+0x157/0x210 init/main.c:1307
> do_initcalls+0x3f/0x80 init/main.c:1323
> kernel_init_freeable+0x435/0x5d0 init/main.c:1555
> kernel_init+0x1d/0x2b0 init/main.c:1444
> ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
> ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
>
> Memory state around the buggy address:
> ffff88805fe2c180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> ffff88805fe2c200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>> ffff88805fe2c280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> ^
> ffff88805fe2c300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> ffff88805fe2c380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> ==================================================================
>
>
> ---
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> syzbot engineers can be reached at [email protected].
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>
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> .
#syz fix: net/sched: unregister lockdep keys in qdisc_create/qdisc_alloc
error path