diff mbox series

[v2] Bluetooth: L2CAP: Fix use-after-free in l2cap_sock_ready_cb

Message ID 20230531053955.2467043-1-iam@sung-woo.kim (mailing list archive)
State Accepted
Commit 8f514cf700508b11946b55eac56bf9acd2b3a884
Headers show
Series [v2] Bluetooth: L2CAP: Fix use-after-free in l2cap_sock_ready_cb | expand

Checks

Context Check Description
tedd_an/pre-ci_am success Success
tedd_an/CheckPatch warning 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.
tedd_an/GitLint fail 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/20230526084038.2199788-1-iam@sung-woo.kim/"
tedd_an/SubjectPrefix success Gitlint PASS
tedd_an/BuildKernel success BuildKernel PASS
tedd_an/CheckAllWarning success CheckAllWarning PASS
tedd_an/CheckSparse success CheckSparse PASS
tedd_an/CheckSmatch success CheckSparse PASS
tedd_an/BuildKernel32 success BuildKernel32 PASS
tedd_an/TestRunnerSetup success TestRunnerSetup PASS
tedd_an/TestRunner_l2cap-tester success TestRunner PASS
tedd_an/TestRunner_iso-tester fail TestRunner_iso-tester: Total: 80, Passed: 75 (93.8%), Failed: 5, Not Run: 0
tedd_an/TestRunner_bnep-tester success TestRunner PASS
tedd_an/TestRunner_mgmt-tester success TestRunner PASS
tedd_an/TestRunner_rfcomm-tester success TestRunner PASS
tedd_an/TestRunner_sco-tester success TestRunner PASS
tedd_an/TestRunner_ioctl-tester success TestRunner PASS
tedd_an/TestRunner_mesh-tester success TestRunner PASS
tedd_an/TestRunner_smp-tester success TestRunner PASS
tedd_an/TestRunner_userchan-tester success TestRunner PASS
tedd_an/IncrementalBuild success Incremental Build PASS

Commit Message

Sungwoo Kim May 31, 2023, 5:39 a.m. UTC 
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 <iam@sung-woo.kim>
---
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/20230526084038.2199788-1-iam@sung-woo.kim/
---
 net/bluetooth/l2cap_sock.c | 2 ++
 1 file changed, 2 insertions(+)

Comments

bluez.test.bot@gmail.com May 31, 2023, 6:36 a.m. UTC | #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/20230526084038.2199788-1-iam@sung-woo.kim/"
##############################
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
diff mbox series

Patch

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);