[PATCH] i386 / desc_empty macro is incorrect
Chuck Ebbert noticed that the desc_empty macro is incorrect. Fix it.
Thankfully, this is not used as a security check, but it can falsely
overwrite TLS segments with carefully chosen base / limits. I do not
believe this is an issue in practice, but it is a kernel bug.
Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Chris Wright <chrisw@osdl.org>
[ x86-64 had the same problem, and the same fix. Linus ]
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/asm-x86_64/processor.h b/include/asm-x86_64/processor.h
index 106f666..85549e6 100644
--- a/include/asm-x86_64/processor.h
+++ b/include/asm-x86_64/processor.h
@@ -32,7 +32,7 @@
#define ID_MASK 0x00200000
#define desc_empty(desc) \
- (!((desc)->a + (desc)->b))
+ (!((desc)->a | (desc)->b))
#define desc_equal(desc1, desc2) \
(((desc1)->a == (desc2)->a) && ((desc1)->b == (desc2)->b))