Commit 543d3500 authored by Punit Agrawal's avatar Punit Agrawal Committed by Rafael J. Wysocki
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ACPI: SPCR: Check for table version when using precise baudrate 



Commit 4d330fe5 ("ACPI: SPCR: Support Precise Baud Rate field")
added support to use the precise baud rate available since SPCR 1.09
(revision 4) but failed to check the version of the table provided by
the firmware.

Accessing an older version of SPCR table causes accesses beyond the
end of the table and can lead to garbage data to be used for the baud
rate.

Check the version of the firmware provided SPCR to ensure that the
precise baudrate is vaild before using it.

Fixes: 4d330fe5 ("ACPI: SPCR: Support Precise Baud Rate field")
Signed-off-by: default avatarPunit Agrawal <punit.agrawal@oss.qualcomm.com>
Link: https://patch.msgid.link/20251024123125.1081612-1-punit.agrawal@oss.qualcomm.com


Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent dc131bcd

drivers/acpi/spcr.c

+1 −1
Original line number Diff line number Diff line
@@ -155,7 +155,7 @@ int __init acpi_parse_spcr(bool enable_earlycon, bool enable_console) 
	 * Baud Rate field. If this field is zero or not present, Configured

	 * Baud Rate is used.

	 */

	if (table->precise_baudrate)

	if (table->header.revision >= 4 && table->precise_baudrate)

		baud_rate = table->precise_baudrate;

	else switch (table->baud_rate) {

	case 0: