[RESEND] Bluetooth: btusb: medaitek: fix double free of skb in coredump

Commit Message

Sean Wang April 17, 2024, 11:27 p.m. UTC

From: Sean Wang <[e-mail]>

hci_devcd_append() would free the skb on error so the caller don't
have to free it again otherwise it would cause the double free of skb.

Fixes: 0b7015132878 ("Bluetooth: btusb: mediatek: add MediaTek devcoredump support")
Reported-by : Dan Carpenter <[e-mail]>
Signed-off-by: Sean Wang <[e-mail]>
---
 drivers/bluetooth/btmtk.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

Comments

[e-mail] April 17, 2024, 11:57 p.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=845618

---Test result---

Test Summary:
CheckPatch                    PASS      0.64 seconds
GitLint                       PASS      0.29 seconds
SubjectPrefix                 PASS      0.11 seconds
BuildKernel                   PASS      29.93 seconds
CheckAllWarning               PASS      32.68 seconds
CheckSparse                   PASS      37.67 seconds
CheckSmatch                   FAIL      35.64 seconds
BuildKernel32                 PASS      28.65 seconds
TestRunnerSetup               PASS      518.27 seconds
TestRunner_l2cap-tester       PASS      19.18 seconds
TestRunner_iso-tester         FAIL      35.29 seconds
TestRunner_bnep-tester        PASS      4.93 seconds
TestRunner_mgmt-tester        FAIL      118.55 seconds
TestRunner_rfcomm-tester      PASS      7.75 seconds
TestRunner_sco-tester         PASS      15.37 seconds
TestRunner_ioctl-tester       PASS      8.25 seconds
TestRunner_mesh-tester        PASS      6.15 seconds
TestRunner_smp-tester         PASS      7.00 seconds
TestRunner_userchan-tester    PASS      5.29 seconds
IncrementalBuild              PASS      31.42 seconds

Details
##############################
Test: CheckSmatch - FAIL
Desc: Run smatch tool with source
Output:

Segmentation fault (core dumped)
make[4]: *** [scripts/Makefile.build:244: net/bluetooth/hci_core.o] Error 139
make[4]: *** Deleting file 'net/bluetooth/hci_core.o'
make[3]: *** [scripts/Makefile.build:485: net/bluetooth] Error 2
make[2]: *** [scripts/Makefile.build:485: net] Error 2
make[2]: *** Waiting for unfinished jobs....
Segmentation fault (core dumped)
make[4]: *** [scripts/Makefile.build:244: drivers/bluetooth/bcm203x.o] Error 139
make[4]: *** Deleting file 'drivers/bluetooth/bcm203x.o'
make[4]: *** Waiting for unfinished jobs....
Segmentation fault (core dumped)
make[4]: *** [scripts/Makefile.build:244: drivers/bluetooth/bpa10x.o] Error 139
make[4]: *** Deleting file 'drivers/bluetooth/bpa10x.o'
make[3]: *** [scripts/Makefile.build:485: drivers/bluetooth] Error 2
make[2]: *** [scripts/Makefile.build:485: drivers] Error 2
make[1]: *** [/github/workspace/src/src/Makefile:1919: .] Error 2
make: *** [Makefile:240: __sub-make] Error 2
##############################
Test: TestRunner_iso-tester - FAIL
Desc: Run iso-tester with test-runner
Output:
Total: 122, Passed: 120 (98.4%), Failed: 2, Not Run: 0

Failed Test Cases
ISO Connect Suspend - Success                        Failed       6.212 seconds
ISO Connect2 Suspend - Success                       Failed       4.232 seconds
##############################
Test: TestRunner_mgmt-tester - FAIL
Desc: Run mgmt-tester with test-runner
Output:
Total: 492, Passed: 486 (98.8%), Failed: 4, Not Run: 2

Failed Test Cases
LL Privacy - Add Device 5 (2 Devices to RL)          Failed       0.164 seconds
LL Privacy - Add Device 6 (RL is full)               Failed       0.194 seconds
LL Privacy - Add Device 7 (AL is full)               Failed       0.216 seconds
LL Privacy - Remove Device 4 (Disable Adv)           Timed out    1.877 seconds


---
Regards,
Linux Bluetooth

Markus Elfring April 18, 2024, 9:40 a.m. UTC | #2

> hci_devcd_append() would free the skb on error so the caller don't
> have to free it again otherwise it would cause the double free of skb.

I hope that a typo will be avoided in the subsystem specification
for the final commit.

Regards,
Markus

Luiz Augusto von Dentz April 19, 2024, 7:42 p.m. UTC | #3

Hi Markus,

On Thu, Apr 18, 2024 at 5:40 AM Markus Elfring <[e-mail]> wrote:
>
> > hci_devcd_append() would free the skb on error so the caller don't
> > have to free it again otherwise it would cause the double free of skb.
>
> I hope that a typo will be avoided in the subsystem specification
> for the final commit.

Are you talking about medaitek or is there another typo?


> Regards,
> Markus

[e-mail] April 19, 2024, 7:50 p.m. UTC | #4

Hello:

This patch was applied to bluetooth/bluetooth-next.git (master)
by Luiz Augusto von Dentz <[e-mail]>:

On Wed, 17 Apr 2024 16:27:38 -0700 you wrote:
> From: Sean Wang <[e-mail]>
> 
> hci_devcd_append() would free the skb on error so the caller don't
> have to free it again otherwise it would cause the double free of skb.
> 
> Fixes: 0b7015132878 ("Bluetooth: btusb: mediatek: add MediaTek devcoredump support")
> Reported-by : Dan Carpenter <[e-mail]>
> Signed-off-by: Sean Wang <[e-mail]>
> 
> [...]

Here is the summary with links:
  - [RESEND] Bluetooth: btusb: medaitek: fix double free of skb in coredump
    https://git.kernel.org/bluetooth/bluetooth-next/c/6764ab72237d

You are awesome, thank you!

Markus Elfring April 19, 2024, 7:56 p.m. UTC | #5

>> I hope that a typo will be avoided in the subsystem specification
>> for the final commit.
>
> Are you talking about medaitek

Yes.

Do you prefer references for mediatek here?


> or is there another typo?

Not yet.

Regards,
Markus

Patch

diff --git a/drivers/bluetooth/btmtk.c b/drivers/bluetooth/btmtk.c
index ac8ebccd3507..812fd2a8f853 100644
--- a/drivers/bluetooth/btmtk.c
+++ b/drivers/bluetooth/btmtk.c
@@ -380,8 +380,10 @@  int btmtk_process_coredump(struct hci_dev *hdev, struct sk_buff *skb)
 	switch (data->cd_info.state) {
 	case HCI_DEVCOREDUMP_IDLE:
 		err = hci_devcd_init(hdev, MTK_COREDUMP_SIZE);
-		if (err < 0)
+		if (err < 0) {
+			kfree_skb(skb);
 			break;
+		}
 		data->cd_info.cnt = 0;
 
 		/* It is supposed coredump can be done within 5 seconds */
@@ -407,9 +409,6 @@  int btmtk_process_coredump(struct hci_dev *hdev, struct sk_buff *skb)
 		break;
 	}
 
-	if (err < 0)
-		kfree_skb(skb);
-
 	return err;
 }
 EXPORT_SYMBOL_GPL(btmtk_process_coredump);