Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 878c98c0 authored by Subhash Jadavani's avatar Subhash Jadavani Committed by David Keitel
Browse files

scsi: ufs: fix failure to read the string descriptor 



While reading variable size descriptors (like string descriptor), some UFS
devices may report the "LENGTH" (field in "Transaction Specific fields" of
Query Response UPIU) same as what was requested in Query Request UPIU
instead of reporting the actual size of the variable size descriptor.
Although it's safe to ignore the "LENGTH" field for variable size
descriptors as we can always derive the length of the descriptor from
the descriptor header fields. Hence this change impose the length match
check only for fixed size descriptors (for which we always request the
correct size as part of Query Request UPIU).

Change-Id: I6be74b3e139b876275c265524cb6ee8489f3737c
Signed-off-by: default avatarSubhash Jadavani <subhashj@codeaurora.org>
parent 9d89b6c4

drivers/scsi/ufs/ufshcd.c

+31 −7
Original line number Diff line number Diff line
@@ -2174,14 +2174,38 @@ static int ufshcd_read_desc_param(struct ufs_hba *hba, 
				      desc_id, desc_index, 0, desc_buf,

				      &buff_len);



	if (ret || (buff_len != desc_buf[QUERY_DESC_LENGTH_OFFSET]) ||

			(desc_buf[QUERY_DESC_DESC_TYPE_OFFSET] != desc_id)) {

		dev_err(hba->dev, "%s: Failed reading descriptor. desc_id %d, param_offset %d, buff_len %d ,index %d, ret %d",

			__func__, desc_id, param_offset, buff_len,

			desc_index, ret);

		if (!ret)

	if (ret) {

		dev_err(hba->dev, "%s: Failed reading descriptor. desc_id %d, desc_index %d, param_offset %d, ret %d",

			__func__, desc_id, desc_index, param_offset, ret);



		goto out;

	}



	/* Sanity check */

	if (desc_buf[QUERY_DESC_DESC_TYPE_OFFSET] != desc_id) {

		dev_err(hba->dev, "%s: invalid desc_id %d in descriptor header",

			__func__, desc_buf[QUERY_DESC_DESC_TYPE_OFFSET]);

		ret = -EINVAL;

		goto out;

	}



	/*

	 * While reading variable size descriptors (like string descriptor),

	 * some UFS devices may report the "LENGTH" (field in "Transaction

	 * Specific fields" of Query Response UPIU) same as what was requested

	 * in Query Request UPIU instead of reporting the actual size of the

	 * variable size descriptor.

	 * Although it's safe to ignore the "LENGTH" field for variable size

	 * descriptors as we can always derive the length of the descriptor from

	 * the descriptor header fields. Hence this change impose the length

	 * match check only for fixed size descriptors (for which we always

	 * request the correct size as part of Query Request UPIU).

	 */

	if ((desc_id != QUERY_DESC_IDN_STRING) &&

	    (buff_len != desc_buf[QUERY_DESC_LENGTH_OFFSET])) {

		dev_err(hba->dev, "%s: desc_buf length mismatch: buff_len %d, buff_len(desc_header) %d",

			__func__, buff_len, desc_buf[QUERY_DESC_LENGTH_OFFSET]);

		ret = -EINVAL;

		goto out;

	}