[PATCH 6.1.y 1/2] usb: typec: fix potential array underflow in ucsi_ccg_sync_control()

[PATCH 6.1.y 1/2] usb: typec: fix potential array underflow in ucsi_ccg_sync_control()

[bin.lan.cn]

From: Dan Carpenter <dan.carpenter@linaro.org>

[ Upstream commit e56aac6e5a25630645607b6856d4b2a17b2311a5 ]

The "command" variable can be controlled by the user via debugfs.  The
worry is that if con_index is zero then "&uc->ucsi->connector[con_index
- 1]" would be an array underflow.

Fixes: 170a6726d0e2 ("usb: typec: ucsi: add support for separate DP altmode devices")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/c69ef0b3-61b0-4dde-98dd-97b97f81d912@stanley.mountain
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[The function ucsi_ccg_sync_write() is renamed to ucsi_ccg_sync_control()
in commit 13f2ec3115c8 ("usb: typec: ucsi:simplify command sending API").
Apply this patch to ucsi_ccg_sync_write() in 6.1.y accordingly.]
Signed-off-by: Bin Lan <bin.lan.cn@windriver.com>
Signed-off-by: He Zhe <zhe.he@windriver.com>
---
Build test passed.
---
 drivers/usb/typec/ucsi/ucsi_ccg.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/usb/typec/ucsi/ucsi_ccg.c b/drivers/usb/typec/ucsi/ucsi_ccg.c
index 8e500fe41e78..4801d783bd0c 100644
--- a/drivers/usb/typec/ucsi/ucsi_ccg.c
+++ b/drivers/usb/typec/ucsi/ucsi_ccg.c
@@ -585,6 +585,10 @@ static int ucsi_ccg_sync_write(struct ucsi *ucsi, unsigned int offset,
 		    uc->has_multiple_dp) {
 			con_index = (uc->last_cmd_sent >> 16) &
 				    UCSI_CMD_CONNECTOR_MASK;
+			if (con_index == 0) {
+				ret = -EINVAL;
+				goto unlock;
+			}
 			con = &uc->ucsi->connector[con_index - 1];
 			ucsi_ccg_update_set_new_cam_cmd(uc, con, (u64 *)val);
 		}
@@ -600,6 +604,7 @@ static int ucsi_ccg_sync_write(struct ucsi *ucsi, unsigned int offset,
 err_clear_bit:
 	clear_bit(DEV_CMD_PENDING, &uc->flags);
 	pm_runtime_put_sync(uc->dev);
+unlock:
 	mutex_unlock(&uc->lock);
 
 	return ret;
-- 
2.34.1

[PATCH 6.1.y 2/2] usb: typec: fix pm usage counter imbalance in ucsi_ccg_sync_control()

[bin.lan.cn]

From: GONG Ruiqi <gongruiqi1@huawei.com>

[ Upstream commit b0e525d7a22ea350e75e2aec22e47fcfafa4cacd ]

The error handling for the case `con_index == 0` should involve dropping
the pm usage counter, as ucsi_ccg_sync_control() gets it at the
beginning. Fix it.

Cc: stable <stable@kernel.org>
Fixes: e56aac6e5a25 ("usb: typec: fix potential array underflow in ucsi_ccg_sync_control()")
Signed-off-by: GONG Ruiqi <gongruiqi1@huawei.com>
Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20250107015750.2778646-1-gongruiqi1@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[Minor context change fixed.]
Signed-off-by: Bin Lan <bin.lan.cn@windriver.com>
Signed-off-by: He Zhe <zhe.he@windriver.com>
---
Build test passed.
---
 drivers/usb/typec/ucsi/ucsi_ccg.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/typec/ucsi/ucsi_ccg.c b/drivers/usb/typec/ucsi/ucsi_ccg.c
index 4801d783bd0c..e690b6e53480 100644
--- a/drivers/usb/typec/ucsi/ucsi_ccg.c
+++ b/drivers/usb/typec/ucsi/ucsi_ccg.c
@@ -587,7 +587,7 @@ static int ucsi_ccg_sync_write(struct ucsi *ucsi, unsigned int offset,
 				    UCSI_CMD_CONNECTOR_MASK;
 			if (con_index == 0) {
 				ret = -EINVAL;
-				goto unlock;
+				goto err_put;
 			}
 			con = &uc->ucsi->connector[con_index - 1];
 			ucsi_ccg_update_set_new_cam_cmd(uc, con, (u64 *)val);
@@ -603,8 +603,8 @@ static int ucsi_ccg_sync_write(struct ucsi *ucsi, unsigned int offset,
 
 err_clear_bit:
 	clear_bit(DEV_CMD_PENDING, &uc->flags);
+err_put:
 	pm_runtime_put_sync(uc->dev);
-unlock:
 	mutex_unlock(&uc->lock);
 
 	return ret;
-- 
2.34.1

Re: [PATCH 6.1.y 2/2] usb: typec: fix pm usage counter imbalance in ucsi_ccg_sync_control()

[Sasha Levin]

[ Sasha's backport helper bot ]

Hi,

✅ All tests passed successfully. No issues detected.
No action required from the submitter.

The upstream commit SHA1 provided is correct: b0e525d7a22ea350e75e2aec22e47fcfafa4cacd

WARNING: Author mismatch between patch and upstream commit:
Backport author: bin.lan.cn@windriver.com
Commit author: GONG Ruiqi<gongruiqi1@huawei.com>

Status in newer kernel trees:
6.14.y | Present (exact SHA1)
6.12.y | Present (different SHA1: 976544bdb40a)
6.6.y | Present (different SHA1: e8336d3c9ab7)

Note: The patch differs from the upstream commit:
---
1:  b0e525d7a22ea < -:  ------------- usb: typec: fix pm usage counter imbalance in ucsi_ccg_sync_control()
-:  ------------- > 1:  3f0ebfaf79640 usb: typec: fix pm usage counter imbalance in ucsi_ccg_sync_control()
---

Results of testing on various branches:

| Branch                    | Patch Apply | Build Test |
|---------------------------|-------------|------------|
| stable/linux-6.6.y        |  Success    |  Success   |

Re: [PATCH 6.1.y 1/2] usb: typec: fix potential array underflow in ucsi_ccg_sync_control()

[Sasha Levin]

[ Sasha's backport helper bot ]

Hi,

Summary of potential issues:
⚠️ Found follow-up fixes in mainline

The upstream commit SHA1 provided is correct: e56aac6e5a25630645607b6856d4b2a17b2311a5

WARNING: Author mismatch between patch and upstream commit:
Backport author: bin.lan.cn@windriver.com
Commit author: Dan Carpenter<dan.carpenter@linaro.org>

Status in newer kernel trees:
6.14.y | Present (exact SHA1)
6.12.y | Present (different SHA1: 56971710cd54)
6.6.y | Present (different SHA1: 0e66fd8e5a2e)

Found fixes commits:
b0e525d7a22e usb: typec: fix pm usage counter imbalance in ucsi_ccg_sync_control()

Note: The patch differs from the upstream commit:
---
1:  e56aac6e5a256 < -:  ------------- usb: typec: fix potential array underflow in ucsi_ccg_sync_control()
-:  ------------- > 1:  8a00c49b69f2c usb: typec: fix potential array underflow in ucsi_ccg_sync_control()
---

Results of testing on various branches:

| Branch                    | Patch Apply | Build Test |
|---------------------------|-------------|------------|
| stable/linux-6.1.y        |  Success    |  Success   |