Re: [PATCH] soc: qcom: mdt_loader: Detect truncated read of segments

From: Sibi Sankar
Date: Thu Apr 08 2021 - 07:02:27 EST



Hey Bjorn,

Thanks for the patch!

On 1/8/21 4:55 AM, Bjorn Andersson wrote:
Given that no validation of how much data the firmware loader read in
for a given segment truncated segment files would best case result in a
hash verification failure, without any indication of what went wrong.

Improve this by validating that the firmware loader did return the
amount of data requested.

Fixes: 445c2410a449 ("soc: qcom: mdt_loader: Use request_firmware_into_buf()")
Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
---
drivers/soc/qcom/mdt_loader.c | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/drivers/soc/qcom/mdt_loader.c b/drivers/soc/qcom/mdt_loader.c
index 24cd193dec55..e01d18e9ad2b 100644
--- a/drivers/soc/qcom/mdt_loader.c
+++ b/drivers/soc/qcom/mdt_loader.c
@@ -253,6 +253,14 @@ static int __qcom_mdt_load(struct device *dev, const struct firmware *fw,
break;
}
+ if (seg_fw->size != phdr->p_filesz) {
+ dev_err(dev,
+ "failed to load segment %d from truncated file %s\n",
+ i, fw_name);
+ ret = -EINVAL;
+ break;

seg_fw has to be released on error condition as well.
With ^^ fixed you can have my R-b.

Reviewed-by: Sibi Sankar <sibis@xxxxxxxxxxxxxx>

+ }
+
release_firmware(seg_fw);
}


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