[PATCH v2 1/3] tpm: acpi: Call acpi_put_table() to fix memory leak

From: Hanjun Guo
Date: Thu Nov 17 2022 - 06:39:44 EST


The start and length of the event log area are obtained from
TPM2 or TCPA table, so we call acpi_get_table() to get the
ACPI information, but the acpi_get_table() should be coupled with
acpi_put_table() to release the ACPI memory, add the acpi_put_table()
properly to fix the memory leak.

While we are at it, remove the redundant empty line at the
end of the tpm_read_log_acpi().

Fixes: 0bfb23746052 ("tpm: Move eventlog files to a subdirectory")
Fixes: 85467f63a05c ("tpm: Add support for event log pointer found in TPM2 ACPI table")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Hanjun Guo <guohanjun@xxxxxxxxxx>
---
drivers/char/tpm/eventlog/acpi.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/char/tpm/eventlog/acpi.c b/drivers/char/tpm/eventlog/acpi.c
index 1b18ce5..0913d3eb 100644
--- a/drivers/char/tpm/eventlog/acpi.c
+++ b/drivers/char/tpm/eventlog/acpi.c
@@ -90,16 +90,21 @@ int tpm_read_log_acpi(struct tpm_chip *chip)
return -ENODEV;

if (tbl->header.length <
- sizeof(*tbl) + sizeof(struct acpi_tpm2_phy))
+ sizeof(*tbl) + sizeof(struct acpi_tpm2_phy)) {
+ acpi_put_table((struct acpi_table_header *)tbl);
return -ENODEV;
+ }

tpm2_phy = (void *)tbl + sizeof(*tbl);
len = tpm2_phy->log_area_minimum_length;

start = tpm2_phy->log_area_start_address;
- if (!start || !len)
+ if (!start || !len) {
+ acpi_put_table((struct acpi_table_header *)tbl);
return -ENODEV;
+ }

+ acpi_put_table((struct acpi_table_header *)tbl);
format = EFI_TCG2_EVENT_LOG_FORMAT_TCG_2;
} else {
/* Find TCPA entry in RSDT (ACPI_LOGICAL_ADDRESSING) */
@@ -120,8 +125,10 @@ int tpm_read_log_acpi(struct tpm_chip *chip)
break;
}

+ acpi_put_table((struct acpi_table_header *)buff);
format = EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2;
}
+
if (!len) {
dev_warn(&chip->dev, "%s: TCPA log area empty\n", __func__);
return -EIO;
@@ -156,5 +163,4 @@ int tpm_read_log_acpi(struct tpm_chip *chip)
kfree(log->bios_event_log);
log->bios_event_log = NULL;
return ret;
-
}
--
1.7.12.4