Changeset e13daa5d in mainline for kernel/arch/amd64/include/cpu.h

Timestamp:

2008-03-19T21:13:49Z (16 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

047aa46

Parents:

20b8bf3

Message:

Fortify ia32 and amd64 kernels against mallicious uspace applications that set
DF prior to entering the kernel. For AMD64 syscalls, we don't use the CLD
instruction, but make use of the SFMASK MSR instead. Simics works fine with
it, but QEMU seems to have a problem.

File:

• kernel/arch/amd64/include/cpu.h (modified) (1 diff)

kernel/arch/amd64/include/cpu.h

@@ -36 +36 @@
 #define KERN_amd64_CPU_H_
 
-#define RFLAGS_IF       (1 << 9)
-#define RFLAGS_RF       (1 << 16)
+#define RFLAGS_IF       (1 << 9)
+#define RFLAGS_DF       (1 << 10)
+#define RFLAGS_RF       (1 << 16)
 
 #define EFER_MSR_NUM    0xc0000080