...so drm_getunique() is trying to copy some uninitialized data to
userspace. The ECX register contains the number of words that are
left to copy -- so there are 5 * 4 = 20 bytes left. The offset of the
first uninitialized byte (counting from the start of the string) is
also 20 (i.e. 0xf65d2294&((1 << 5)-1) == 20). So somebody tried to
copy 40 bytes when the string was only 19 long.
In drm_set_busid() we have this code:
dev->unique_len = 40;
dev->unique = drm_alloc(dev->unique_len + 1, DRM_MEM_DRIVER);
...
len = snprintf(dev->unique, dev->unique_len, pci:%04x:%02x:%02x.%d",
...so it seems that dev->unique is never updated to reflect the
actual length of the string. The remaining bytes (20 in this case)
are random uninitialized bytes that are copied into userspace.
This patch fixes the problem by setting dev->unique_len after the
snprintf().
airlied- I've had to fix this up to store the alloced size so
we have it for drm_free later.
Reported-by: Sitsofe Wheeler <sitsofe@yahoo.com>
Signed-off-by: Vegard Nossum <vegardno@thuin.ifi.uio.no>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This is step one towards having multiple masters sharing a drm
device in order to get fast-user-switching to work.
It splits out the information associated with the drm master
into a separate kref counted structure, and allocates this when
a master opens the device node. It also allows the current master
to abdicate (say while VT switched), and a new master to take over
the hardware.
It moves the Intel and radeon drivers to using the sarea from
within the new master structures.
Signed-off-by: Dave Airlie <airlied@redhat.com>
With the coming of kernel based modesetting and the memory manager stuff,
the everything in one directory approach was getting very ugly and
starting to be unmanageable.
This restructures the drm along the lines of other kernel components.
It creates a drivers/gpu/drm directory and moves the hw drivers into
subdirectores. It moves the includes into an include/drm, and
sets up the unifdef for the userspace headers we should be exporting.
Signed-off-by: Dave Airlie <airlied@redhat.com>
