Patrick Georgi has submitted this change. ( https://review.coreboot.org/c/coreboot/+/42892 )
Change subject: acpi: Avoid freeing a device twice ......................................................................
acpi: Avoid freeing a device twice
The current implementation of acpi_dp_write() frees the node after it has written it.
If the structure contains a ACPI_DP_TYPE_CHILD then a recursive call to acpi_dp_write() frees the child and then frees it again when returning from the call. This results in a double free.
Split the implementation into two steps, one that ones and one that frees. This is easier to understand and fixes the bug.
Note: This likely has no effect in coreboot since it doesn't seem to have a proper free() implementation. But it might gain one one day.
BUG=none
Signed-off-by: Simon Glass sjg@chromium.org Change-Id: Ife3917af10bc35a3c3eee38d8292f927ef15409d Reviewed-on: https://review.coreboot.org/c/coreboot/+/42892 Reviewed-by: Patrick Georgi pgeorgi@google.com Tested-by: build bot (Jenkins) no-reply@coreboot.org --- M src/acpi/device.c 1 file changed, 7 insertions(+), 2 deletions(-)
Approvals: build bot (Jenkins): Verified Patrick Georgi: Looks good to me, approved
diff --git a/src/acpi/device.c b/src/acpi/device.c index 9ce86eb..b119abd 100644 --- a/src/acpi/device.c +++ b/src/acpi/device.c @@ -770,7 +770,7 @@ return false; }
-void acpi_dp_write(struct acpi_dp *table) +static void acpi_dp_write_(struct acpi_dp *table) { struct acpi_dp *dp, *prop; char *dp_count; @@ -826,7 +826,12 @@ /* Recursively parse children into separate tables */ for (dp = prop; dp; dp = dp->next) if (dp->type == ACPI_DP_TYPE_CHILD) - acpi_dp_write(dp->child); + acpi_dp_write_(dp->child); +} + +void acpi_dp_write(struct acpi_dp *table) +{ + acpi_dp_write_(table);
/* Clean up */ acpi_dp_free(table);