[PATCH v10 04/18] uprobes/x86: Use existing definitions for segment override prefixes

From: Ricardo Neri
Date: Fri Oct 27 2017 - 16:32:01 EST


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>
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxx>
Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Cc: Denys Vlasenko <dvlasenk@xxxxxxxxxx>
Cc: Srikar Dronamraju <srikar@xxxxxxxxxxxxxxxxxx>
Cc: Ravi V. Shankar <ravi.v.shankar@xxxxxxxxx>
Signed-off-by: Ricardo Neri <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;
}
}
--
2.7.4