The ->cap fields of struct acpi_video_device and struct acpi_video_bus
are 1B each, not 4B. The oversized memset()'s corrupted the subsequent
list_head fields. This resulted in silent corruption without
CONFIG_DEBUG_LIST and BUG's with it. This patch uses sizeof() to pass
the proper bounds to the memset() calls and thereby correct the bugs.
Included as a MIME attachment is a compressed dmesg from an affected
system. The patch was seen to resolve the issue on the affected system.
vs. 2.6.24-rc5
Signed-off-by: William Irwin <[email protected]>
-- wli
diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index 44a0d9b..7895d57 100644
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -577,7 +577,7 @@ static void acpi_video_device_find_cap(struct acpi_video_device *device)
struct acpi_video_device_brightness *br = NULL;
- memset(&device->cap, 0, 4);
+ memset(&device->cap, 0, sizeof(struct acpi_video_device_cap));
if (ACPI_SUCCESS(acpi_get_handle(device->dev->handle, "_ADR", &h_dummy1))) {
device->cap._ADR = 1;
@@ -697,7 +697,7 @@ static void acpi_video_bus_find_cap(struct acpi_video_bus *video)
{
acpi_handle h_dummy1;
- memset(&video->cap, 0, 4);
+ memset(&video->cap, 0, sizeof(struct acpi_video_bus_cap));
if (ACPI_SUCCESS(acpi_get_handle(video->device->handle, "_DOS", &h_dummy1))) {
video->cap._DOS = 1;
}
William Lee Irwin III writes:
> The ->cap fields of struct acpi_video_device and struct acpi_video_bus
> are 1B each, not 4B. The oversized memset()'s corrupted the subsequent
> list_head fields. This resulted in silent corruption without
> CONFIG_DEBUG_LIST and BUG's with it. This patch uses sizeof() to pass
> the proper bounds to the memset() calls and thereby correct the bugs.
>
> Included as a MIME attachment is a compressed dmesg from an affected
> system. The patch was seen to resolve the issue on the affected system.
>
> vs. 2.6.24-rc5
>
> Signed-off-by: William Irwin <[email protected]>
>
>
> -- wli
>
> diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
> index 44a0d9b..7895d57 100644
> --- a/drivers/acpi/video.c
> +++ b/drivers/acpi/video.c
> @@ -577,7 +577,7 @@ static void acpi_video_device_find_cap(struct acpi_video_device *device)
> struct acpi_video_device_brightness *br = NULL;
>
>
> - memset(&device->cap, 0, 4);
> + memset(&device->cap, 0, sizeof(struct acpi_video_device_cap));
IMO the memset(ptr, 0, sizeof(*ptr)) idiom is both safer
and avoids having to write an uninteresting type name.
On Wed, Dec 12, 2007 at 12:48:09PM +0100, Mikael Pettersson wrote:
> IMO the memset(ptr, 0, sizeof(*ptr)) idiom is both safer
> and avoids having to write an uninteresting type name.
How about this, then?
The ->cap fields of struct acpi_video_device and struct acpi_video_bus
are 1B each, not 4B. The oversized memset()'s corrupted the subsequent
list_head fields. This resulted in silent corruption without
CONFIG_DEBUG_LIST and BUG's with it. This patch uses sizeof() to pass
the proper bounds to the memset() calls and thereby correct the bugs.
The patch was seen to resolve the issue on the affected system.
vs. 2.6.24-rc5
Signed-off-by: William Irwin <[email protected]>
diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index 44a0d9b..bd77e81 100644
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -577,7 +577,7 @@ static void acpi_video_device_find_cap(struct acpi_video_device *device)
struct acpi_video_device_brightness *br = NULL;
- memset(&device->cap, 0, 4);
+ memset(&device->cap, 0, sizeof(device->cap));
if (ACPI_SUCCESS(acpi_get_handle(device->dev->handle, "_ADR", &h_dummy1))) {
device->cap._ADR = 1;
@@ -697,7 +697,7 @@ static void acpi_video_bus_find_cap(struct acpi_video_bus *video)
{
acpi_handle h_dummy1;
- memset(&video->cap, 0, 4);
+ memset(&video->cap, 0, sizeof(video->cap));
if (ACPI_SUCCESS(acpi_get_handle(video->device->handle, "_DOS", &h_dummy1))) {
video->cap._DOS = 1;
}
William Lee Irwin III writes:
> On Wed, Dec 12, 2007 at 12:48:09PM +0100, Mikael Pettersson wrote:
> > IMO the memset(ptr, 0, sizeof(*ptr)) idiom is both safer
> > and avoids having to write an uninteresting type name.
>
> How about this, then?
Looks good.
Acked-by: Mikael Pettersson <[email protected]>
>
> The ->cap fields of struct acpi_video_device and struct acpi_video_bus
> are 1B each, not 4B. The oversized memset()'s corrupted the subsequent
> list_head fields. This resulted in silent corruption without
> CONFIG_DEBUG_LIST and BUG's with it. This patch uses sizeof() to pass
> the proper bounds to the memset() calls and thereby correct the bugs.
>
> The patch was seen to resolve the issue on the affected system.
>
> vs. 2.6.24-rc5
>
> Signed-off-by: William Irwin <[email protected]>
>
> diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
> index 44a0d9b..bd77e81 100644
> --- a/drivers/acpi/video.c
> +++ b/drivers/acpi/video.c
> @@ -577,7 +577,7 @@ static void acpi_video_device_find_cap(struct acpi_video_device *device)
> struct acpi_video_device_brightness *br = NULL;
>
>
> - memset(&device->cap, 0, 4);
> + memset(&device->cap, 0, sizeof(device->cap));
>
> if (ACPI_SUCCESS(acpi_get_handle(device->dev->handle, "_ADR", &h_dummy1))) {
> device->cap._ADR = 1;
> @@ -697,7 +697,7 @@ static void acpi_video_bus_find_cap(struct acpi_video_bus *video)
> {
> acpi_handle h_dummy1;
>
> - memset(&video->cap, 0, 4);
> + memset(&video->cap, 0, sizeof(video->cap));
> if (ACPI_SUCCESS(acpi_get_handle(video->device->handle, "_DOS", &h_dummy1))) {
> video->cap._DOS = 1;
> }
> --
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>
On Wednesday 12 December 2007 07:12, Mikael Pettersson wrote:
> Acked-by: Mikael Pettersson <[email protected]>
applied.
thanks,
-Len