[PATCH] unwinder: more sanity checks in Dwarf2 unwinder

Tighten the requirements on both input to and output from the Dwarf2
unwinder.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andi Kleen <ak@suse.de>

2 files changed, 6 insertions, 14 deletions

diff --git a/include/asm-i386/unwind.h b/include/asm-i386/unwind.h
index 601fc67bd775..aa2c931e30db 100644
--- a/include/asm-i386/unwind.h
+++ b/include/asm-i386/unwind.h
@@ -79,17 +79,13 @@ extern asmlinkage int arch_unwind_init_running(struct unwind_frame_info *,
                                                                           void *arg),
                                                void *arg);
 
-static inline int arch_unw_user_mode(const struct unwind_frame_info *info)
+static inline int arch_unw_user_mode(/*const*/ struct unwind_frame_info *info)
 {
-#if 0 /* This can only work when selector register and EFLAGS saves/restores
-         are properly annotated (and tracked in UNW_REGISTER_INFO). */
-        return user_mode_vm(&info->regs);
-#else
-        return info->regs.eip < PAGE_OFFSET
+        return user_mode_vm(&info->regs)
+               || info->regs.eip < PAGE_OFFSET
                || (info->regs.eip >= __fix_to_virt(FIX_VDSO)
-                    && info->regs.eip < __fix_to_virt(FIX_VDSO) + PAGE_SIZE)
+                   && info->regs.eip < __fix_to_virt(FIX_VDSO) + PAGE_SIZE)
                || info->regs.esp < PAGE_OFFSET;
-#endif
 }
 
 #else
diff --git a/include/asm-x86_64/unwind.h b/include/asm-x86_64/unwind.h
index 2e7ff10fd775..2f6349e48717 100644
--- a/include/asm-x86_64/unwind.h
+++ b/include/asm-x86_64/unwind.h
@@ -87,14 +87,10 @@ extern int arch_unwind_init_running(struct unwind_frame_info *,
 
 static inline int arch_unw_user_mode(const struct unwind_frame_info *info)
 {
-#if 0 /* This can only work when selector register saves/restores
-         are properly annotated (and tracked in UNW_REGISTER_INFO). */
-        return user_mode(&info->regs);
-#else
-        return (long)info->regs.rip >= 0
+        return user_mode(&info->regs)
+               || (long)info->regs.rip >= 0
                || (info->regs.rip >= VSYSCALL_START && info->regs.rip < VSYSCALL_END)
                || (long)info->regs.rsp >= 0;
-#endif
 }
 
 #else