arm64: Treat all entry code as non-kprobe-able

Entry symbols are not kprobe safe. So blacklist them for kprobing.

Signed-off-by: Pratyush Anand <panand@redhat.com>
Signed-off-by: David A. Long <dave.long@linaro.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
[catalin.marinas@arm.com: Do not include syscall wrappers in .entry.text]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
index 12e8d2b..492a265 100644 (file)
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -242,6 +242,7 @@ tsk .req    x28             // current thread_info
 /*
  * Exception vectors.
  */
+       .pushsection ".entry.text", "ax"
 
        .align  11
 ENTRY(vectors)
@@ -774,6 +775,8 @@ __ni_sys_trace:
        bl      do_ni_syscall
        b       __sys_trace_return
 
+       .popsection                             // .entry.text
+
 /*
  * Special system call wrappers.
  */

diff --git a/arch/arm64/kernel/probes/kprobes.c b/arch/arm64/kernel/probes/kprobes.c
index 4496801..0fe2b65 100644 (file)
--- a/arch/arm64/kernel/probes/kprobes.c
+++ b/arch/arm64/kernel/probes/kprobes.c
@@ -30,6 +30,7 @@
 #include <asm/insn.h>
 #include <asm/uaccess.h>
 #include <asm/irq.h>
+#include <asm-generic/sections.h>
 
 #include "decode-insn.h"
 
@@ -519,6 +520,31 @@ int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
        return 1;
 }
 
+bool arch_within_kprobe_blacklist(unsigned long addr)
+{
+       extern char __idmap_text_start[], __idmap_text_end[];
+       extern char __hyp_idmap_text_start[], __hyp_idmap_text_end[];
+
+       if ((addr >= (unsigned long)__kprobes_text_start &&
+           addr < (unsigned long)__kprobes_text_end) ||
+           (addr >= (unsigned long)__entry_text_start &&
+           addr < (unsigned long)__entry_text_end) ||
+           (addr >= (unsigned long)__idmap_text_start &&
+           addr < (unsigned long)__idmap_text_end) ||
+           !!search_exception_tables(addr))
+               return true;
+
+       if (!is_kernel_in_hyp_mode()) {
+               if ((addr >= (unsigned long)__hyp_text_start &&
+                   addr < (unsigned long)__hyp_text_end) ||
+                   (addr >= (unsigned long)__hyp_idmap_text_start &&
+                   addr < (unsigned long)__hyp_idmap_text_end))
+                       return true;
+       }
+
+       return false;
+}
+
 int __init arch_init_kprobes(void)
 {
        return 0;

diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S
index 075ce32..9f59394 100644 (file)
--- a/arch/arm64/kernel/vmlinux.lds.S
+++ b/arch/arm64/kernel/vmlinux.lds.S
@@ -118,6 +118,7 @@ SECTIONS
                        __exception_text_end = .;
                        IRQENTRY_TEXT
                        SOFTIRQENTRY_TEXT
+                       ENTRY_TEXT
                        TEXT_TEXT
                        SCHED_TEXT
                        LOCK_TEXT