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bus: mhi: core: Validate channel ID when processing command completions

PATCH Applied Bhaumik Bhatt 4 participants 6 messages Apr 26, 2021 – May 24, 2021

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Bhaumik Bhatt

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#0 lore raw

PATCH 1/1 bus: mhi: core: Validate channel ID when processing command completions

MHI reads the channel ID from the event ring element sent by the device which can be any value between 0 and 255. In order to prevent any out of bound accesses, add a check against the maximum number of channels supported by the controller and those channels not configured yet so as to skip processing of that event ring element.

Fixes 1d3173a3bae7 ("bus: mhi: core: Add support for processing events from client device")
Signed-off-by Bhaumik Bhatt <[email protected]>
---
 drivers/bus/mhi/core/main.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)
drivers/bus/mhi/core/main.c +10 -5
index 22acde1..ed07421 100644
@@ -773,11 +773,16 @@ static void mhi_process_cmd_completion(struct mhi_controller *mhi_cntrl,
 	cmd_pkt = mhi_to_virtual(mhi_ring, ptr);
 
 	chan = MHI_TRE_GET_CMD_CHID(cmd_pkt);
-	mhi_chan = &mhi_cntrl->mhi_chan[chan];
-	write_lock_bh(&mhi_chan->lock);
-	mhi_chan->ccs = MHI_TRE_GET_EV_CODE(tre);
-	complete(&mhi_chan->completion);
-	write_unlock_bh(&mhi_chan->lock);
+	WARN_ON(chan >= mhi_cntrl->max_chan);
+
+	if (chan < mhi_cntrl->max_chan &&
+	    mhi_cntrl->mhi_chan[chan].configured) {
+		mhi_chan = &mhi_cntrl->mhi_chan[chan];
+		write_lock_bh(&mhi_chan->lock);
+		mhi_chan->ccs = MHI_TRE_GET_EV_CODE(tre);
+		complete(&mhi_chan->completion);
+		write_unlock_bh(&mhi_chan->lock);
+	}
 
 	mhi_del_ring_element(mhi_cntrl, mhi_ring);
 }
Signature · 2 lines
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project
Reviewed-by on v1 1/1
#1 lore raw
Quoted 10 lines · Bhaumik Bhatt

MHI reads the channel ID from the event ring element sent by the device which can be any value between 0 and 255. In order to prevent any out of bound accesses, add a check against the maximum number of channels supported by the controller and those channels not configured yet so as to skip processing of that event ring element.

Fixes 1d3173a3bae7 ("bus: mhi: core: Add support for processing events from client device")
Signed-off-by Bhaumik Bhatt <[email protected]>

---

Reviewed-by Hemant Kumar <[email protected]>
Signature · 2 lines
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project
Reviewed-by on v1 1/1
#2 lore raw
In reply to Bhaumik Bhatt
Quoted 10 lines · Bhaumik Bhatt

MHI reads the channel ID from the event ring element sent by the device which can be any value between 0 and 255. In order to prevent any out of bound accesses, add a check against the maximum number of channels supported by the controller and those channels not configured yet so as to skip processing of that event ring element.

Fixes 1d3173a3bae7 ("bus: mhi: core: Add support for processing events from client device")
Signed-off-by Bhaumik Bhatt <[email protected]>

---

Reviewed-by Jeffrey Hugo <[email protected]>
Reviewed-by on v1 1/1
#3 lore raw
In reply to Bhaumik Bhatt
Quoted 9 lines · Bhaumik Bhatt

MHI reads the channel ID from the event ring element sent by the device which can be any value between 0 and 255. In order to prevent any out of bound accesses, add a check against the maximum number of channels supported by the controller and those channels not configured yet so as to skip processing of that event ring element.

Fixes 1d3173a3bae7 ("bus: mhi: core: Add support for processing events from client device")
Signed-off-by Bhaumik Bhatt <[email protected]>
Reviewed-by Manivannan Sadhasivam <[email protected]>

Thanks,
Mani

Quoted 34 lines
---
 drivers/bus/mhi/core/main.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)
drivers/bus/mhi/core/main.c +10 -5
index 22acde1..ed07421 100644
@@ -773,11 +773,16 @@ static void mhi_process_cmd_completion(struct mhi_controller *mhi_cntrl,
 	cmd_pkt = mhi_to_virtual(mhi_ring, ptr);
 
 	chan = MHI_TRE_GET_CMD_CHID(cmd_pkt);
-	mhi_chan = &mhi_cntrl->mhi_chan[chan];
-	write_lock_bh(&mhi_chan->lock);
-	mhi_chan->ccs = MHI_TRE_GET_EV_CODE(tre);
-	complete(&mhi_chan->completion);
-	write_unlock_bh(&mhi_chan->lock);
+	WARN_ON(chan >= mhi_cntrl->max_chan);
+
+	if (chan < mhi_cntrl->max_chan &&
+	    mhi_cntrl->mhi_chan[chan].configured) {
+		mhi_chan = &mhi_cntrl->mhi_chan[chan];
+		write_lock_bh(&mhi_chan->lock);
+		mhi_chan->ccs = MHI_TRE_GET_EV_CODE(tre);
+		complete(&mhi_chan->completion);
+		write_unlock_bh(&mhi_chan->lock);
+	}
 
 	mhi_del_ring_element(mhi_cntrl, mhi_ring);
 }
Signature · 2 lines
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project
Applied
#4 lore raw
In reply to Bhaumik Bhatt
Quoted 9 lines · Bhaumik Bhatt

MHI reads the channel ID from the event ring element sent by the device which can be any value between 0 and 255. In order to prevent any out of bound accesses, add a check against the maximum number of channels supported by the controller and those channels not configured yet so as to skip processing of that event ring element.

Fixes 1d3173a3bae7 ("bus: mhi: core: Add support for processing events from client device")
Signed-off-by Bhaumik Bhatt <[email protected]>

Applied to mhi-next!

Thanks,
Mani

Quoted 34 lines
---
 drivers/bus/mhi/core/main.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)
drivers/bus/mhi/core/main.c +10 -5
index 22acde1..ed07421 100644
@@ -773,11 +773,16 @@ static void mhi_process_cmd_completion(struct mhi_controller *mhi_cntrl,
 	cmd_pkt = mhi_to_virtual(mhi_ring, ptr);
 
 	chan = MHI_TRE_GET_CMD_CHID(cmd_pkt);
-	mhi_chan = &mhi_cntrl->mhi_chan[chan];
-	write_lock_bh(&mhi_chan->lock);
-	mhi_chan->ccs = MHI_TRE_GET_EV_CODE(tre);
-	complete(&mhi_chan->completion);
-	write_unlock_bh(&mhi_chan->lock);
+	WARN_ON(chan >= mhi_cntrl->max_chan);
+
+	if (chan < mhi_cntrl->max_chan &&
+	    mhi_cntrl->mhi_chan[chan].configured) {
+		mhi_chan = &mhi_cntrl->mhi_chan[chan];
+		write_lock_bh(&mhi_chan->lock);
+		mhi_chan->ccs = MHI_TRE_GET_EV_CODE(tre);
+		complete(&mhi_chan->completion);
+		write_unlock_bh(&mhi_chan->lock);
+	}
 
 	mhi_del_ring_element(mhi_cntrl, mhi_ring);
 }
Signature · 2 lines
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project
#5 lore raw
Quoted 8 lines · Manivannan Sadhasivam
Quoted 7 lines · Bhaumik Bhatt

MHI reads the channel ID from the event ring element sent by the device which can be any value between 0 and 255. In order to prevent any out of bound accesses, add a check against the maximum number of channels supported by the controller and those channels not configured yet so as to skip processing of that event ring element.

Quoted 5 lines
Quoted 2 lines
Fixes 1d3173a3bae7 ("bus: mhi: core: Add support for processing events from client device")
Signed-off-by Bhaumik Bhatt <[email protected]>

Applied to mhi-next!

Sorry this has been applied to mhi-next!

Thanks,
Mani

Quoted 37 lines

Thanks,
Mani

Quoted 34 lines
---
 drivers/bus/mhi/core/main.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)
drivers/bus/mhi/core/main.c +10 -5
index 22acde1..ed07421 100644
@@ -773,11 +773,16 @@ static void mhi_process_cmd_completion(struct mhi_controller *mhi_cntrl,
 	cmd_pkt = mhi_to_virtual(mhi_ring, ptr);
 
 	chan = MHI_TRE_GET_CMD_CHID(cmd_pkt);
-	mhi_chan = &mhi_cntrl->mhi_chan[chan];
-	write_lock_bh(&mhi_chan->lock);
-	mhi_chan->ccs = MHI_TRE_GET_EV_CODE(tre);
-	complete(&mhi_chan->completion);
-	write_unlock_bh(&mhi_chan->lock);
+	WARN_ON(chan >= mhi_cntrl->max_chan);
+
+	if (chan < mhi_cntrl->max_chan &&
+	    mhi_cntrl->mhi_chan[chan].configured) {
+		mhi_chan = &mhi_cntrl->mhi_chan[chan];
+		write_lock_bh(&mhi_chan->lock);
+		mhi_chan->ccs = MHI_TRE_GET_EV_CODE(tre);
+		complete(&mhi_chan->completion);
+		write_unlock_bh(&mhi_chan->lock);
+	}
 
 	mhi_del_ring_element(mhi_cntrl, mhi_ring);
 }
Signature · 2 lines
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project