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KASAN: slab-use-after-free Read in sco_chan_del (2)

Status: upstream: reported on 2024/09/23 09:02
Subsystems: bluetooth
[Documentation on labels]
Reported-by: syzbot+b70293d0c3fc68076e49@syzkaller.appspotmail.com
First crash: 77d, last: 44d
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [bluetooth?] KASAN: slab-use-after-free Read in sco_chan_del (2) 0 (1) 2024/09/23 09:02
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: slab-use-after-free Read in sco_chan_del bluetooth 1 406d 400d 0/28 auto-obsoleted due to no activity on 2024/02/02 12:39
upstream KASAN: slab-use-after-free Write in sco_chan_del bluetooth C done 19 435d 569d 23/28 fixed on 2023/10/12 12:47

Sample crash report:
==================================================================
BUG: KASAN: slab-use-after-free in sco_chan_del+0x460/0x4b0 net/bluetooth/sco.c:174
Read of size 8 at addr ffff88802a8f5600 by task syz.0.1372/8986

CPU: 3 UID: 0 PID: 8986 Comm: syz.0.1372 Not tainted 6.11.0-syzkaller-03917-ga940d9a43e62 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0xc3/0x620 mm/kasan/report.c:488
 kasan_report+0xd9/0x110 mm/kasan/report.c:601
 sco_chan_del+0x460/0x4b0 net/bluetooth/sco.c:174
 __sco_sock_close+0xf2/0x640 net/bluetooth/sco.c:459
 sco_sock_close net/bluetooth/sco.c:474 [inline]
 sco_sock_release+0x6f/0x2d0 net/bluetooth/sco.c:1249
 __sock_release+0xb0/0x270 net/socket.c:659
 sock_close+0x1c/0x30 net/socket.c:1427
 __fput+0x3f6/0xb60 fs/file_table.c:431
 task_work_run+0x14e/0x250 kernel/task_work.c:228
 get_signal+0x1ca/0x2770 kernel/signal.c:2690
 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:310
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218
 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6f8957def9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f6f8a362038 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: fffffffffffffffc RBX: 00007f6f89736058 RCX: 00007f6f8957def9
RDX: 0000000000000008 RSI: 0000000020000040 RDI: 0000000000000005
RBP: 00007f6f895f0b76 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f6f89736058 R15: 00007fff399424c8
 </TASK>

Allocated by task 8722:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:370 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:387
 kmalloc_noprof include/linux/slab.h:690 [inline]
 kzalloc_noprof include/linux/slab.h:816 [inline]
 sco_conn_add.part.0+0x43/0x2d0 net/bluetooth/sco.c:137
 sco_conn_add net/bluetooth/sco.c:266 [inline]
 sco_connect net/bluetooth/sco.c:278 [inline]
 sco_sock_connect+0x6c9/0xb00 net/bluetooth/sco.c:596
 __sys_connect_file+0x14d/0x190 net/socket.c:2067
 __sys_connect+0x149/0x170 net/socket.c:2084
 __do_sys_connect net/socket.c:2094 [inline]
 __se_sys_connect net/socket.c:2091 [inline]
 __x64_sys_connect+0x72/0xb0 net/socket.c:2091
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 5343:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
 poison_slab_object+0xf7/0x160 mm/kasan/common.c:240
 __kasan_slab_free+0x32/0x50 mm/kasan/common.c:256
 kasan_slab_free include/linux/kasan.h:184 [inline]
 slab_free_hook mm/slub.c:2250 [inline]
 slab_free mm/slub.c:4474 [inline]
 kfree+0x12a/0x3b0 mm/slub.c:4595
 sco_conn_del+0x1d4/0x2a0 net/bluetooth/sco.c:214
 sco_connect_cfm+0x257/0xc10 net/bluetooth/sco.c:1364
 hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
 hci_conn_failed+0x1c3/0x340 net/bluetooth/hci_conn.c:1262
 hci_abort_conn_sync+0x75a/0xb50 net/bluetooth/hci_sync.c:5586
 abort_conn_sync+0x197/0x360 net/bluetooth/hci_conn.c:2914
 hci_cmd_sync_work+0x1a4/0x410 net/bluetooth/hci_sync.c:328
 process_one_work+0x9c5/0x1b40 kernel/workqueue.c:3231
 process_scheduled_works kernel/workqueue.c:3312 [inline]
 worker_thread+0x6c8/0xf00 kernel/workqueue.c:3393
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

The buggy address belongs to the object at ffff88802a8f5600
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 0 bytes inside of
 freed 256-byte region [ffff88802a8f5600, ffff88802a8f5700)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2a8f4
head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xfdffffff(slab)
raw: 00fff00000000040 ffff88801ac42b40 ffffea0000a54280 dead000000000004
raw: 0000000000000000 0000000000100010 00000001fdffffff 0000000000000000
head: 00fff00000000040 ffff88801ac42b40 ffffea0000a54280 dead000000000004
head: 0000000000000000 0000000000100010 00000001fdffffff 0000000000000000
head: 00fff00000000001 ffffea0000aa3d01 ffffffffffffffff 0000000000000000
head: 0000000000000002 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0x1d2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 5431, tgid 5429 (syz.2.13), ts 54219801688, free_ts 53733128813
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1500
 prep_new_page mm/page_alloc.c:1508 [inline]
 get_page_from_freelist+0x1351/0x2e50 mm/page_alloc.c:3446
 __alloc_pages_noprof+0x22b/0x2460 mm/page_alloc.c:4702
 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline]
 alloc_pages_node_noprof include/linux/gfp.h:296 [inline]
 alloc_slab_page+0x4e/0xf0 mm/slub.c:2319
 allocate_slab mm/slub.c:2482 [inline]
 new_slab+0x84/0x260 mm/slub.c:2535
 ___slab_alloc+0xdac/0x1870 mm/slub.c:3721
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3811
 __slab_alloc_node mm/slub.c:3864 [inline]
 slab_alloc_node mm/slub.c:4026 [inline]
 __do_kmalloc_node mm/slub.c:4158 [inline]
 __kmalloc_noprof+0x367/0x400 mm/slub.c:4171
 kmalloc_noprof include/linux/slab.h:694 [inline]
 kmalloc_array_noprof include/linux/slab.h:735 [inline]
 security_inode_init_security+0x140/0x390 security/security.c:1823
 shmem_mknod+0xe9/0x240 mm/shmem.c:3432
 shmem_mkdir+0x31/0x60 mm/shmem.c:3486
 vfs_mkdir+0x57d/0x860 fs/namei.c:4257
 do_mkdirat+0x301/0x3a0 fs/namei.c:4280
 __do_sys_mkdirat fs/namei.c:4295 [inline]
 __se_sys_mkdirat fs/namei.c:4293 [inline]
 __x64_sys_mkdirat+0x83/0xb0 fs/namei.c:4293
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 5340 tgid 5340 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1101 [inline]
 free_unref_page+0x64a/0xe40 mm/page_alloc.c:2619
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4e/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x192/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:322
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3989 [inline]
 slab_alloc_node mm/slub.c:4038 [inline]
 __do_kmalloc_node mm/slub.c:4158 [inline]
 __kmalloc_node_noprof+0x1c3/0x430 mm/slub.c:4165
 __kvmalloc_node_noprof+0x9d/0x1a0 mm/util.c:650
 xt_jumpstack_alloc net/netfilter/x_tables.c:1355 [inline]
 xt_replace_table+0x1c7/0x910 net/netfilter/x_tables.c:1394
 __do_replace+0x1d9/0x9c0 net/ipv4/netfilter/arp_tables.c:912
 do_replace net/ipv6/netfilter/ip6_tables.c:1158 [inline]
 do_ip6t_set_ctl+0x94b/0xc40 net/ipv6/netfilter/ip6_tables.c:1644
 nf_setsockopt+0x8a/0xf0 net/netfilter/nf_sockopt.c:101
 ipv6_setsockopt+0x135/0x170 net/ipv6/ipv6_sockglue.c:998
 tcp_setsockopt+0xa4/0x100 net/ipv4/tcp.c:4029
 do_sock_setsockopt+0x222/0x480 net/socket.c:2330
 __sys_setsockopt+0x1a4/0x270 net/socket.c:2353
 __do_sys_setsockopt net/socket.c:2362 [inline]
 __se_sys_setsockopt net/socket.c:2359 [inline]
 __x64_sys_setsockopt+0xbd/0x160 net/socket.c:2359
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83

Memory state around the buggy address:
 ffff88802a8f5500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88802a8f5580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88802a8f5600: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff88802a8f5680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88802a8f5700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/09/18 09:17 upstream a940d9a43e62 c673ca06 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream KASAN: slab-use-after-free Read in sco_chan_del
2024/10/21 21:29 upstream 42f7652d3eb5 a93682b3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root KFENCE: use-after-free in sco_chan_del
* Struck through repros no longer work on HEAD.