在 2024/10/10 23:52, Marc Zyngier 写道:
On Thu, 10 Oct 2024 15:47:03 +0100,
Zheng Zengkai <zhengzengkai@xxxxxxxxxx> wrote:
As suggested by Marc and Lorenzo, first we need to check whether
the platform_timer pointer is within gtdt bounds (< gtdt_end) before
de-referencing what it points at to detect the (first) platform
timer entry length and check that next platform_timer pointer is
within gtdt_end too. Now we do that only in next_platform_timer()
for subsequent platform timers.
So add check against table length (gtdt_end) for the first platform
timer entry.
Suggested-by: Marc Zyngier <maz@xxxxxxxxxx>
Suggested-by: Lorenzo Pieralisi <lpieralisi@xxxxxxxxxx>
Signed-off-by: Zheng Zengkai <zhengzengkai@xxxxxxxxxx>
---
drivers/acpi/arm64/gtdt.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/acpi/arm64/gtdt.c b/drivers/acpi/arm64/gtdt.c
index c0e77c1c8e09..f249af1ed1cd 100644
--- a/drivers/acpi/arm64/gtdt.c
+++ b/drivers/acpi/arm64/gtdt.c
@@ -177,7 +177,8 @@ int __init acpi_gtdt_init(struct acpi_table_header *table,
}
platform_timer = (void *)gtdt + gtdt->platform_timer_offset;
- if (platform_timer < (void *)table + sizeof(struct acpi_table_gtdt)) {
+ if (platform_timer < (void *)table + sizeof(struct acpi_table_gtdt) ||
+ platform_timer >= acpi_gtdt_desc.gtdt_end) {
pr_err(FW_BUG "invalid timer data.\n");
return -EINVAL;
}
You are only checking the base pointer for the platform_timer
array. This doesn't say anything about the *size* of that array (or at
least its first element), and whether that actually fits in the table.
M.
Yes, I will send v2 to check against gtdt_end for both entry and length
of each array element.
Thanks!
