tpm/eventlog: Don't abort tpm_read_log on faulty ACPI address

[ Upstream commit 80a6c216b1 ]

tpm_read_log_acpi() should return -ENODEV when no eventlog from the ACPI
table is found. If the firmware vendor includes an invalid log address
we are unable to map from the ACPI memory and tpm_read_log() returns -EIO
which would abort discovery of the eventlog.

Change the return value from -EIO to -ENODEV when acpi_os_map_iomem()
fails to map the event log.

The following hardware was used to test this issue:
    Framework Laptop (Pre-production)
    BIOS: INSYDE Corp, Revision: 3.2
    TPM Device: NTC, Firmware Revision: 7.2

Dump of the faulty ACPI TPM2 table:
    [000h 0000   4]                    Signature : "TPM2"    [Trusted Platform Module hardware interface Table]
    [004h 0004   4]                 Table Length : 0000004C
    [008h 0008   1]                     Revision : 04
    [009h 0009   1]                     Checksum : 2B
    [00Ah 0010   6]                       Oem ID : "INSYDE"
    [010h 0016   8]                 Oem Table ID : "TGL-ULT"
    [018h 0024   4]                 Oem Revision : 00000002
    [01Ch 0028   4]              Asl Compiler ID : "ACPI"
    [020h 0032   4]        Asl Compiler Revision : 00040000

    [024h 0036   2]               Platform Class : 0000
    [026h 0038   2]                     Reserved : 0000
    [028h 0040   8]              Control Address : 0000000000000000
    [030h 0048   4]                 Start Method : 06 [Memory Mapped I/O]

    [034h 0052  12]            Method Parameters : 00 00 00 00 00 00 00 00 00 00 00 00
    [040h 0064   4]           Minimum Log Length : 00010000
    [044h 0068   8]                  Log Address : 000000004053D000

Fixes: 0cf577a03f ("tpm: Fix handling of missing event log")
Tested-by: Erkki Eilonen <erkki@bearmetal.eu>
Signed-off-by: Morten Linderud <morten@linderud.pw>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/char/tpm/eventlog/acpi.c

@@ -143,8 +143,12 @@ int tpm_read_log_acpi(struct tpm_chip *chip)
 
 	ret = -EIO;
 	virt = acpi_os_map_iomem(start, len);
-	if (!virt)
+	if (!virt) {
+		dev_warn(&chip->dev, "%s: Failed to map ACPI memory\n", __func__);
+		/* try EFI log next */
+		ret = -ENODEV;
 		goto err;
+	}
 
 	memcpy_fromio(log->bios_event_log, virt, len);