syzbot


KASAN: use-after-free Read in raw_release

Status: fixed on 2023/10/12 12:48
Subsystems: can
[Documentation on labels]
Fix commit: 11c9027c983e can: raw: fix lockdep issue in raw_release()
First crash: 301d, last: 301d

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in read_pnet include/net/net_namespace.h:383 [inline]
BUG: KASAN: use-after-free in dev_net include/linux/netdevice.h:2590 [inline]
BUG: KASAN: use-after-free in raw_release+0x960/0x9b0 net/can/raw.c:395
Read of size 8 at addr ffff88802b9b8670 by task syz-executor.1/7705

CPU: 0 PID: 7705 Comm: syz-executor.1 Not tainted 6.5.0-rc3-syzkaller-00176-g13d2618b48f1 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:364 [inline]
 print_report+0xc4/0x620 mm/kasan/report.c:475
 kasan_report+0xda/0x110 mm/kasan/report.c:588
 read_pnet include/net/net_namespace.h:383 [inline]
 dev_net include/linux/netdevice.h:2590 [inline]
 raw_release+0x960/0x9b0 net/can/raw.c:395
 __sock_release+0xcd/0x290 net/socket.c:654
 sock_close+0x1c/0x20 net/socket.c:1386
 __fput+0x3fd/0xac0 fs/file_table.c:384
 task_work_run+0x14d/0x240 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+0x210/0x240 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
 syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:297
 do_syscall_64+0x44/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fb7e927b9da
Code: 48 3d 00 f0 ff ff 77 48 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 7c 24 0c e8 03 7f 02 00 8b 7c 24 0c 89 c2 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 36 89 d7 89 44 24 0c e8 63 7f 02 00 8b 44 24
RSP: 002b:00007ffd15e54c90 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 000000000000000a RCX: 00007fb7e927b9da
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000009
RBP: 00007fb7e939d980 R08: 0000001b2fb20000 R09: 000000000000040e
R10: 000000008190df57 R11: 0000000000000293 R12: 000000000011244a
R13: ffffffffffffffff R14: 00007fb7e8e00000 R15: 0000000000112109
 </TASK>

The buggy address belongs to the physical page:
page:ffffea0000ae6e00 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2b9b8
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000000 ffffea0001e32208 ffffea0000ae7c08 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x446dc0(GFP_KERNEL_ACCOUNT|__GFP_NOWARN|__GFP_RETRY_MAYFAIL|__GFP_COMP|__GFP_ZERO), pid 5067, tgid 5067 (syz-executor.1), ts 153775196806, free_ts 1123753306319
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x2d2/0x350 mm/page_alloc.c:1570
 prep_new_page mm/page_alloc.c:1577 [inline]
 get_page_from_freelist+0x10a9/0x31e0 mm/page_alloc.c:3221
 __alloc_pages+0x1d0/0x4a0 mm/page_alloc.c:4477
 __alloc_pages_node include/linux/gfp.h:237 [inline]
 alloc_pages_node include/linux/gfp.h:260 [inline]
 __kmalloc_large_node+0x87/0x1c0 mm/slab_common.c:1126
 __do_kmalloc_node mm/slab_common.c:973 [inline]
 __kmalloc_node.cold+0x5/0xdd mm/slab_common.c:992
 kmalloc_node include/linux/slab.h:602 [inline]
 kvmalloc_node+0x6f/0x1a0 mm/util.c:604
 kvmalloc include/linux/slab.h:720 [inline]
 kvzalloc include/linux/slab.h:728 [inline]
 alloc_netdev_mqs+0x9b/0x1240 net/core/dev.c:10594
 rtnl_create_link+0xc9c/0xfd0 net/core/rtnetlink.c:3336
 rtnl_newlink_create net/core/rtnetlink.c:3462 [inline]
 __rtnl_newlink+0x1075/0x18c0 net/core/rtnetlink.c:3689
 rtnl_newlink+0x67/0xa0 net/core/rtnetlink.c:3702
 rtnetlink_rcv_msg+0x439/0xd30 net/core/rtnetlink.c:6428
 netlink_rcv_skb+0x16b/0x440 net/netlink/af_netlink.c:2549
 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline]
 netlink_unicast+0x539/0x800 net/netlink/af_netlink.c:1365
 netlink_sendmsg+0x93c/0xe30 net/netlink/af_netlink.c:1914
 sock_sendmsg_nosec net/socket.c:725 [inline]
 sock_sendmsg+0xd9/0x180 net/socket.c:748
 __sys_sendto+0x255/0x340 net/socket.c:2134
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1161 [inline]
 free_unref_page_prepare+0x508/0xb90 mm/page_alloc.c:2348
 free_unref_page+0x33/0x3b0 mm/page_alloc.c:2443
 kvfree+0x47/0x50 mm/util.c:650
 device_release+0xa1/0x240 drivers/base/core.c:2484
 kobject_cleanup lib/kobject.c:682 [inline]
 kobject_release lib/kobject.c:713 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x1f7/0x5b0 lib/kobject.c:730
 netdev_run_todo+0x7dd/0x11d0 net/core/dev.c:10366
 rtnl_unlock net/core/rtnetlink.c:151 [inline]
 rtnetlink_rcv_msg+0x446/0xd30 net/core/rtnetlink.c:6429
 netlink_rcv_skb+0x16b/0x440 net/netlink/af_netlink.c:2549
 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline]
 netlink_unicast+0x539/0x800 net/netlink/af_netlink.c:1365
 netlink_sendmsg+0x93c/0xe30 net/netlink/af_netlink.c:1914
 sock_sendmsg_nosec net/socket.c:725 [inline]
 sock_sendmsg+0xd9/0x180 net/socket.c:748
 ____sys_sendmsg+0x6ac/0x940 net/socket.c:2494
 ___sys_sendmsg+0x135/0x1d0 net/socket.c:2548
 __sys_sendmsg+0x117/0x1e0 net/socket.c:2577
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Memory state around the buggy address:
 ffff88802b9b8500: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88802b9b8580: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88802b9b8600: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                             ^
 ffff88802b9b8680: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88802b9b8700: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/08/01 22:26 net 13d2618b48f1 df07ffe8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce KASAN: use-after-free Read in raw_release
* Struck through repros no longer work on HEAD.