l2cap_sock_release(sk) frees sk. However, sk's children are still alive
and point to the already free'd sk's address.
To fix this, l2cap_sock_release(sk) also cleans sk's children.
==================================================================
BUG: KASAN: use-after-free in l2cap_sock_ready_cb+0xb7/0x100 net/bluetooth/l2cap_sock.c:1650
Read of size 8 at addr ffff888104617aa8 by task kworker/u3:0/276
CPU: 0 PID: 276 Comm: kworker/u3:0 Not tainted 6.2.0-00001-gef397bd4d5fb-dirty #59
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
Workqueue: hci2 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x72/0x95 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:306 [inline]
print_report+0x175/0x478 mm/kasan/report.c:417
kasan_report+0xb1/0x130 mm/kasan/report.c:517
l2cap_sock_ready_cb+0xb7/0x100 net/bluetooth/l2cap_sock.c:1650
l2cap_chan_ready+0x10e/0x1e0 net/bluetooth/l2cap_core.c:1386
l2cap_config_req+0x753/0x9f0 net/bluetooth/l2cap_core.c:4480
l2cap_bredr_sig_cmd net/bluetooth/l2cap_core.c:5739 [inline]
l2cap_sig_channel net/bluetooth/l2cap_core.c:6509 [inline]
l2cap_recv_frame+0xe2e/0x43c0 net/bluetooth/l2cap_core.c:7788
l2cap_recv_acldata+0x6ed/0x7e0 net/bluetooth/l2cap_core.c:8506
hci_acldata_packet net/bluetooth/hci_core.c:3813 [inline]
hci_rx_work+0x66e/0xbc0 net/bluetooth/hci_core.c:4048
process_one_work+0x4ea/0x8e0 kernel/workqueue.c:2289
worker_thread+0x364/0x8e0 kernel/workqueue.c:2436
kthread+0x1b9/0x200 kernel/kthread.c:376
ret_from_fork+0x2c/0x50 arch/x86/entry/entry_64.S:308
</TASK>
Allocated by task 288:
kasan_save_stack+0x22/0x50 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+0x82/0x90 mm/kasan/common.c:383
kasan_kmalloc include/linux/kasan.h:211 [inline]
__do_kmalloc_node mm/slab_common.c:968 [inline]
__kmalloc+0x5a/0x140 mm/slab_common.c:981
kmalloc include/linux/slab.h:584 [inline]
sk_prot_alloc+0x113/0x1f0 net/core/sock.c:2040
sk_alloc+0x36/0x3c0 net/core/sock.c:2093
l2cap_sock_alloc.constprop.0+0x39/0x1c0 net/bluetooth/l2cap_sock.c:1852
l2cap_sock_create+0x10d/0x220 net/bluetooth/l2cap_sock.c:1898
bt_sock_create+0x183/0x290 net/bluetooth/af_bluetooth.c:132
__sock_create+0x226/0x380 net/socket.c:1518
sock_create net/socket.c:1569 [inline]
__sys_socket_create net/socket.c:1606 [inline]
__sys_socket_create net/socket.c:1591 [inline]
__sys_socket+0x112/0x200 net/socket.c:1639
__do_sys_socket net/socket.c:1652 [inline]
__se_sys_socket net/socket.c:1650 [inline]
__x64_sys_socket+0x40/0x50 net/socket.c:1650
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3f/0x90 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x72/0xdc
Freed by task 288:
kasan_save_stack+0x22/0x50 mm/kasan/common.c:45
kasan_set_track+0x25/0x30 mm/kasan/common.c:52
kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:523
____kasan_slab_free mm/kasan/common.c:236 [inline]
____kasan_slab_free mm/kasan/common.c:200 [inline]
__kasan_slab_free+0x10a/0x190 mm/kasan/common.c:244
kasan_slab_free include/linux/kasan.h:177 [inline]
slab_free_hook mm/slub.c:1781 [inline]
slab_free_freelist_hook mm/slub.c:1807 [inline]
slab_free mm/slub.c:3787 [inline]
__kmem_cache_free+0x88/0x1f0 mm/slub.c:3800
sk_prot_free net/core/sock.c:2076 [inline]
__sk_destruct+0x347/0x430 net/core/sock.c:2168
sk_destruct+0x9c/0xb0 net/core/sock.c:2183
__sk_free+0x82/0x220 net/core/sock.c:2194
sk_free+0x7c/0xa0 net/core/sock.c:2205
sock_put include/net/sock.h:1991 [inline]
l2cap_sock_kill+0x256/0x2b0 net/bluetooth/l2cap_sock.c:1257
l2cap_sock_release+0x1a7/0x220 net/bluetooth/l2cap_sock.c:1428
__sock_release+0x80/0x150 net/socket.c:650
sock_close+0x19/0x30 net/socket.c:1368
__fput+0x17a/0x5c0 fs/file_table.c:320
task_work_run+0x132/0x1c0 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+0x113/0x120 kernel/entry/common.c:203
__syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline]
syscall_exit_to_user_mode+0x21/0x50 kernel/entry/common.c:296
do_syscall_64+0x4c/0x90 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x72/0xdc
The buggy address belongs to the object at ffff888104617800
which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 680 bytes inside of
1024-byte region [ffff888104617800, ffff888104617c00)
The buggy address belongs to the physical page:
page:00000000dbca6a80 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888104614000 pfn:0x104614
head:00000000dbca6a80 order:2 compound_mapcount:0 subpages_mapcount:0 compound_pincount:0
flags: 0x200000000010200(slab|head|node=0|zone=2)
raw: 0200000000010200 ffff888100041dc0 ffffea0004212c10 ffffea0004234b10
raw: ffff888104614000 0000000000080002 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff888104617980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888104617a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888104617a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff888104617b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888104617b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
Ack: This bug is found by FuzzBT with a modified Syzkaller. Other
contributors are Ruoyu Wu and Hui Peng.
Signed-off-by: Sungwoo Kim <[email protected]>
---
Changes in v2:
- Fix a compile error: Add a forward declaration for l2cap_sock_cleanup_listen()
- Lint'ed; Remove trailing tabs
- Link to v1: https://lore.kernel.org/lkml/[email protected]/
---
net/bluetooth/l2cap_sock.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/net/bluetooth/l2cap_sock.c b/net/bluetooth/l2cap_sock.c
index eebe25610..947ca580b 100644
--- a/net/bluetooth/l2cap_sock.c
+++ b/net/bluetooth/l2cap_sock.c
@@ -46,6 +46,7 @@ static const struct proto_ops l2cap_sock_ops;
static void l2cap_sock_init(struct sock *sk, struct sock *parent);
static struct sock *l2cap_sock_alloc(struct net *net, struct socket *sock,
int proto, gfp_t prio, int kern);
+static void l2cap_sock_cleanup_listen(struct sock *parent);
bool l2cap_is_socket(struct socket *sock)
{
@@ -1415,6 +1416,7 @@ static int l2cap_sock_release(struct socket *sock)
if (!sk)
return 0;
+ l2cap_sock_cleanup_listen(sk);
bt_sock_unlink(&l2cap_sk_list, sk);
err = l2cap_sock_shutdown(sock, SHUT_RDWR);
--
2.34.1
This is automated email and please do not reply to this email!
Dear submitter,
Thank you for submitting the patches to the linux bluetooth mailing list.
This is a CI test results with your patch series:
PW Link:https://patchwork.kernel.org/project/bluetooth/list/?series=752554
---Test result---
Test Summary:
CheckPatch FAIL 0.94 seconds
GitLint FAIL 0.55 seconds
SubjectPrefix PASS 0.10 seconds
BuildKernel PASS 33.83 seconds
CheckAllWarning PASS 37.66 seconds
CheckSparse PASS 44.32 seconds
CheckSmatch PASS 114.17 seconds
BuildKernel32 PASS 33.46 seconds
TestRunnerSetup PASS 480.27 seconds
TestRunner_l2cap-tester PASS 18.30 seconds
TestRunner_iso-tester FAIL 25.23 seconds
TestRunner_bnep-tester PASS 5.96 seconds
TestRunner_mgmt-tester PASS 121.29 seconds
TestRunner_rfcomm-tester PASS 9.32 seconds
TestRunner_sco-tester PASS 8.74 seconds
TestRunner_ioctl-tester PASS 10.15 seconds
TestRunner_mesh-tester PASS 7.45 seconds
TestRunner_smp-tester PASS 8.54 seconds
TestRunner_userchan-tester PASS 6.27 seconds
IncrementalBuild PASS 32.02 seconds
Details
##############################
Test: CheckPatch - FAIL
Desc: Run checkpatch.pl script
Output:
[v2] Bluetooth: L2CAP: Fix use-after-free in l2cap_sock_ready_cb
WARNING: Possible unwrapped commit description (prefer a maximum 75 chars per line)
#80:
CPU: 0 PID: 276 Comm: kworker/u3:0 Not tainted 6.2.0-00001-gef397bd4d5fb-dirty #59
total: 0 errors, 1 warnings, 0 checks, 14 lines checked
NOTE: For some of the reported defects, checkpatch may be able to
mechanically convert to the typical style using --fix or --fix-inplace.
/github/workspace/src/src/13261484.patch has style problems, please review.
NOTE: Ignored message types: UNKNOWN_COMMIT_ID
NOTE: If any of the errors are false positives, please report
them to the maintainer, see CHECKPATCH in MAINTAINERS.
##############################
Test: GitLint - FAIL
Desc: Run gitlint
Output:
[v2] Bluetooth: L2CAP: Fix use-after-free in l2cap_sock_ready_cb
WARNING: I3 - ignore-body-lines: gitlint will be switching from using Python regex 'match' (match beginning) to 'search' (match anywhere) semantics. Please review your ignore-body-lines.regex option accordingly. To remove this warning, set general.regex-style-search=True. More details: https://jorisroovers.github.io/gitlint/configuration/#regex-style-search
8: B1 Line exceeds max length (92>80): "BUG: KASAN: use-after-free in l2cap_sock_ready_cb+0xb7/0x100 net/bluetooth/l2cap_sock.c:1650"
11: B1 Line exceeds max length (82>80): "CPU: 0 PID: 276 Comm: kworker/u3:0 Not tainted 6.2.0-00001-gef397bd4d5fb-dirty #59"
100: B1 Line exceeds max length (106>80): "page:00000000dbca6a80 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888104614000 pfn:0x104614"
101: B1 Line exceeds max length (89>80): "head:00000000dbca6a80 order:2 compound_mapcount:0 subpages_mapcount:0 compound_pincount:0"
123: B1 Line exceeds max length (85>80): "- Link to v1: https://lore.kernel.org/lkml/[email protected]/"
##############################
Test: TestRunner_iso-tester - FAIL
Desc: Run iso-tester with test-runner
Output:
Total: 80, Passed: 75 (93.8%), Failed: 5, Not Run: 0
Failed Test Cases
ISO AC 6(i) - Success Failed 0.242 seconds
ISO AC 7(i) - Success Failed 0.249 seconds
ISO AC 8(i) - Success Failed 0.243 seconds
ISO AC 9(i) - Success Failed 0.246 seconds
ISO AC 11(i) - Success Failed 0.250 seconds
---
Regards,
Linux Bluetooth
Hello:
This patch was applied to bluetooth/bluetooth-next.git (master)
by Luiz Augusto von Dentz <[email protected]>:
On Wed, 31 May 2023 01:39:56 -0400 you wrote:
> l2cap_sock_release(sk) frees sk. However, sk's children are still alive
> and point to the already free'd sk's address.
> To fix this, l2cap_sock_release(sk) also cleans sk's children.
>
> ==================================================================
> BUG: KASAN: use-after-free in l2cap_sock_ready_cb+0xb7/0x100 net/bluetooth/l2cap_sock.c:1650
> Read of size 8 at addr ffff888104617aa8 by task kworker/u3:0/276
>
> [...]
Here is the summary with links:
- [v2] Bluetooth: L2CAP: Fix use-after-free in l2cap_sock_ready_cb
https://git.kernel.org/bluetooth/bluetooth-next/c/8f514cf70050
You are awesome, thank you!
--
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https://korg.docs.kernel.org/patchwork/pwbot.html