[tip:x86/mpx] uprobes/x86: Use existing definitions for segment override prefixes

[tip-bot for Ricardo Neri]

Commit-ID:  ed40a10431701d683bfd59f7ca01a8c97408cf67
Gitweb:     https://git.kernel.org/tip/ed40a10431701d683bfd59f7ca01a8c97408cf67
Author:     Ricardo Neri <ricardo.neri-calderon@xxxxxxxxxxxxxxx>
AuthorDate: Fri, 27 Oct 2017 13:25:31 -0700
Committer:  Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitDate: Wed, 1 Nov 2017 21:50:08 +0100

uprobes/x86: Use existing definitions for segment override prefixes

Rather than using hard-coded values of the segment override prefixes,
leverage the existing definitions provided in inat.h.

Suggested-by: Borislav Petkov <bp@xxxxxxx>
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@xxxxxxxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Reviewed-by: Borislav Petkov <bp@xxxxxxx>
Cc: Srikar Dronamraju <srikar@xxxxxxxxxxxxxxxxxx>
Cc: "Michael S. Tsirkin" <mst@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: ricardo.neri@xxxxxxxxx
Cc: Paul Gortmaker <paul.gortmaker@xxxxxxxxxxxxx>
Cc: Huang Rui <ray.huang@xxxxxxx>
Cc: Shuah Khan <shuah@xxxxxxxxxx>
Cc: Jonathan Corbet <corbet@xxxxxxx>
Cc: Jiri Slaby <jslaby@xxxxxxx>
Cc: "Ravi V. Shankar" <ravi.v.shankar@xxxxxxxxx>
Cc: Denys Vlasenko <dvlasenk@xxxxxxxxxx>
Cc: Chris Metcalf <cmetcalf@xxxxxxxxxxxx>
Cc: Brian Gerst <brgerst@xxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Chen Yucong <slaoub@xxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Link: https://lkml.kernel.org/r/1509135945-13762-5-git-send-email-ricardo.neri-calderon@xxxxxxxxxxxxxxx

---
 arch/x86/kernel/uprobes.c | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kernel/uprobes.c b/arch/x86/kernel/uprobes.c
index 495c776..a3755d2 100644
--- a/arch/x86/kernel/uprobes.c
+++ b/arch/x86/kernel/uprobes.c
@@ -271,12 +271,15 @@ static bool is_prefix_bad(struct insn *insn)
 	int i;
 
 	for (i = 0; i < insn->prefixes.nbytes; i++) {
-		switch (insn->prefixes.bytes[i]) {
-		case 0x26:	/* INAT_PFX_ES   */
-		case 0x2E:	/* INAT_PFX_CS   */
-		case 0x36:	/* INAT_PFX_DS   */
-		case 0x3E:	/* INAT_PFX_SS   */
-		case 0xF0:	/* INAT_PFX_LOCK */
+		insn_attr_t attr;
+
+		attr = inat_get_opcode_attribute(insn->prefixes.bytes[i]);
+		switch (attr) {
+		case INAT_MAKE_PREFIX(INAT_PFX_ES):
+		case INAT_MAKE_PREFIX(INAT_PFX_CS):
+		case INAT_MAKE_PREFIX(INAT_PFX_DS):
+		case INAT_MAKE_PREFIX(INAT_PFX_SS):
+		case INAT_MAKE_PREFIX(INAT_PFX_LOCK):
 			return true;
 		}
 	}