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

Commit 6e0ad59e authored by Jean Delvare's avatar Jean Delvare
Browse files

firmware: dmi_scan: Trim DMI table length before exporting it 



The SMBIOS v3 entry points specify a maximum length for the DMI table,
not the exact length. Thus there may be garbage after the end-of-table
marker, which we don't want to export to user-space. Adjust dmi_len
when we find the end-of-table marker, so that only the actual table
payload is exported.

Signed-off-by: default avatarJean Delvare <jdelvare@suse.de>
Cc: Ivan Khoronzhuk <ivan.khoronzhuk@globallogic.com>
parent eb4c5ea5

drivers/firmware/dmi_scan.c

+10 −5
Original line number Diff line number Diff line
@@ -108,6 +108,9 @@ static void dmi_decode_table(u8 *buf, 
		if (data - buf < dmi_len - 1)

			decode(dm, private_data);



		data += 2;

		i++;



		/*

		 * 7.45 End-of-Table (Type 127) [SMBIOS reference spec v3.0.0]

		 * For tables behind a 64-bit entry point, we have no item
@@ -118,10 +121,11 @@ static void dmi_decode_table(u8 *buf, 
		 */

		if (!dmi_num && dm->type == DMI_ENTRY_END_OF_TABLE)

			break;



		data += 2;

		i++;

	}



	/* Trim DMI table length if needed */

	if (dmi_len > data - buf)

		dmi_len = data - buf;

}



static phys_addr_t dmi_base;
@@ -130,8 +134,9 @@ static int __init dmi_walk_early(void (*decode)(const struct dmi_header *, 
		void *))

{

	u8 *buf;

	u32 orig_dmi_len = dmi_len;



	buf = dmi_early_remap(dmi_base, dmi_len);

	buf = dmi_early_remap(dmi_base, orig_dmi_len);

	if (buf == NULL)

		return -1;
@@ -139,7 +144,7 @@ static int __init dmi_walk_early(void (*decode)(const struct dmi_header *, 


	add_device_randomness(buf, dmi_len);



	dmi_early_unmap(buf, dmi_len);

	dmi_early_unmap(buf, orig_dmi_len);

	return 0;

}