memory leak in read_adv_mon_features

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 7fca4dee Merge tag 'powerpc-5.9-2' of git://git.kernel.org..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=15ea92a1900000
kernel config: https://syzkaller.appspot.com/x/.config?x=e320bbff976a5cdc
dashboard link: https://syzkaller.appspot.com/bug?extid=f7f6e564f4202d8601c6
compiler: gcc (GCC) 10.1.0-syz 20200507
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1286db9a900000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1143ddf6900000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f7f6e5...@syzkaller.appspotmail.com

BUG: memory leak
unreferenced object 0xffff88812b18e6e0 (size 32):
comm "syz-executor286", pid 6490, jiffies 4294993450 (age 13.120s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 20 00 10 00 00 00 00 00 ........ .......
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<00000000f286b99c>] kmalloc include/linux/slab.h:559 [inline]
[<00000000f286b99c>] read_adv_mon_features+0xa1/0x150 net/bluetooth/mgmt.c:4180
[<00000000f0f16504>] hci_mgmt_cmd net/bluetooth/hci_sock.c:1603 [inline]
[<00000000f0f16504>] hci_sock_sendmsg+0xb01/0xc60 net/bluetooth/hci_sock.c:1738
[<000000001560da71>] sock_sendmsg_nosec net/socket.c:651 [inline]
[<000000001560da71>] sock_sendmsg+0x4c/0x60 net/socket.c:671
[<000000007d7be9f6>] sock_write_iter+0xc5/0x140 net/socket.c:998
[<00000000e3633d41>] call_write_iter include/linux/fs.h:1882 [inline]
[<00000000e3633d41>] new_sync_write+0x173/0x210 fs/read_write.c:503
[<0000000021a87df2>] vfs_write+0x21d/0x280 fs/read_write.c:578
[<0000000003f07ff6>] ksys_write+0xd8/0x120 fs/read_write.c:631
[<0000000003a7df09>] do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
[<000000005ecd28f6>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

BUG: memory leak
unreferenced object 0xffff88812b18e660 (size 32):
comm "syz-executor286", pid 6495, jiffies 4294993998 (age 7.640s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 20 00 10 00 00 00 00 00 ........ .......
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<00000000f286b99c>] kmalloc include/linux/slab.h:559 [inline]
[<00000000f286b99c>] read_adv_mon_features+0xa1/0x150 net/bluetooth/mgmt.c:4180
[<00000000f0f16504>] hci_mgmt_cmd net/bluetooth/hci_sock.c:1603 [inline]
[<00000000f0f16504>] hci_sock_sendmsg+0xb01/0xc60 net/bluetooth/hci_sock.c:1738
[<000000001560da71>] sock_sendmsg_nosec net/socket.c:651 [inline]
[<000000001560da71>] sock_sendmsg+0x4c/0x60 net/socket.c:671
[<000000007d7be9f6>] sock_write_iter+0xc5/0x140 net/socket.c:998
[<00000000e3633d41>] call_write_iter include/linux/fs.h:1882 [inline]
[<00000000e3633d41>] new_sync_write+0x173/0x210 fs/read_write.c:503
[<0000000021a87df2>] vfs_write+0x21d/0x280 fs/read_write.c:578
[<0000000003f07ff6>] ksys_write+0xd8/0x120 fs/read_write.c:631
[<0000000003a7df09>] do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
[<000000005ecd28f6>] entry_SYSCALL_64_after_hwframe+0x44/0xa9



---
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[Peilin Ye]

read_adv_mon_features() is leaking memory. Free `rp` before returning.

Fixes: e5e1e7fd470c ("Bluetooth: Add handler of MGMT_OP_READ_ADV_MONITOR_FEATURES")
Reported-and-tested-by: syzbot+f7f6e5...@syzkaller.appspotmail.com
Signed-off-by: Peilin Ye <yepei...@gmail.com>
---
net/bluetooth/mgmt.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index 5bbe71002fb9..f96251f818fc 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -4157,7 +4157,7 @@ static int read_adv_mon_features(struct sock *sk, struct hci_dev *hdev,
{
struct adv_monitor *monitor = NULL;
struct mgmt_rp_read_adv_monitor_features *rp = NULL;
- int handle;
+ int handle, err;
size_t rp_size = 0;
__u32 supported = 0;
__u16 num_handles = 0;
@@ -4192,9 +4192,13 @@ static int read_adv_mon_features(struct sock *sk, struct hci_dev *hdev,
if (num_handles)
memcpy(&rp->handles, &handles, (num_handles * sizeof(u16)));

- return mgmt_cmd_complete(sk, hdev->id,
- MGMT_OP_READ_ADV_MONITOR_FEATURES,
- MGMT_STATUS_SUCCESS, rp, rp_size);
+ err = mgmt_cmd_complete(sk, hdev->id,
+ MGMT_OP_READ_ADV_MONITOR_FEATURES,
+ MGMT_STATUS_SUCCESS, rp, rp_size);
+
+ kfree(rp);
+
+ return err;
}

static int add_adv_patterns_monitor(struct sock *sk, struct hci_dev *hdev,
--
2.25.1

[Peilin Ye]

read_adv_mon_features() is leaking memory. Free `rp` before returning.

Fixes: e5e1e7fd470c ("Bluetooth: Add handler of MGMT_OP_READ_ADV_MONITOR_FEATURES")
Reported-and-tested-by: syzbot+f7f6e5...@syzkaller.appspotmail.com

Link: https://syzkaller.appspot.com/bug?extid=f7f6e564f4202d8601c6

Signed-off-by: Peilin Ye <yepei...@gmail.com>
---

I forgot the "Link:" tag yesterday. Sorry about that.

Change in v2:
- add a proper "Link:" tag.

[Marcel Holtmann]

Hi Peilin,

> read_adv_mon_features() is leaking memory. Free `rp` before returning.
>
> Fixes: e5e1e7fd470c ("Bluetooth: Add handler of MGMT_OP_READ_ADV_MONITOR_FEATURES")
> Reported-and-tested-by: syzbot+f7f6e5...@syzkaller.appspotmail.com
> Link: https://syzkaller.appspot.com/bug?extid=f7f6e564f4202d8601c6
> Signed-off-by: Peilin Ye <yepei...@gmail.com>
> ---
> I forgot the "Link:" tag yesterday. Sorry about that.
>
> Change in v2:
> - add a proper "Link:" tag.
>
> net/bluetooth/mgmt.c | 12 ++++++++----
> 1 file changed, 8 insertions(+), 4 deletions(-)

patch has been applied to bluetooth-next tree.

Regards

Marcel