Capabilities issue in firmware loader

Capabilities issue in firmware loader

[Oliver Neukum]

Hi,

the firmware loader has a security issue. Firmware on some devices can
write to all memory through DMA. Therefore the ability to feed firmware
to the kernel is equivalent to writing to /dev/kmem. CAP_SYS_RAWIO is
needed to protect itself.
Please apply.

	Regards
		Oliver

Signed-Off-By: Oliver Neukum <oliver@neukum.name>

You can import this changeset into BK by piping this whole message to:
'| bk receive [path to repository]' or apply the patch as usual.

===================================================================


ChangeSet@1.1948, 2004-09-23 17:40:42+02:00, oliver@oenone.homelinux.org
  - require CAP_SYS_RAWIO to change firmware


 firmware_class.c |    2 ++
 1 files changed, 2 insertions(+)


diff -Nru a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
--- a/drivers/base/firmware_class.c	Thu Sep 23 18:57:32 2004
+++ b/drivers/base/firmware_class.c	Thu Sep 23 18:57:32 2004
@@ -235,6 +235,8 @@
 	struct firmware *fw;
 	ssize_t retval;
 
+	if (!capable(CAP_SYS_RAWIO))
+		return -EPERM;
 	down(&fw_lock);
 	fw = fw_priv->fw;
 	if (test_bit(FW_STATUS_DONE, &fw_priv->status)) {

===================================================================


This BitKeeper patch contains the following changesets:
1.1948
## Wrapped with gzip_uu ##


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