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

commit 888b3c8720e0a4033db09ba2364afde6a4763638 upstream.

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

[dave.long@linaro.org: Remove check for hypervisor text]

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 5a3753d09e20d607ab9419cec2d27e3aef50b8b0..efbf9afea3909606133d60f6ba9f133f7b38e4a0 100644 (file)
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -207,6 +207,7 @@ tsk .req    x28             // current thread_info
 /*
  * Exception vectors.
  */
+       .pushsection ".entry.text", "ax"
 
        .align  11
 ENTRY(vectors)
@@ -738,6 +739,8 @@ __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 55e3e01901718caa5e25b2e9ad4a0deac098607a..bb3d380fdb4d100e0b4d7a4c01cf8a92ab819b19 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"
 
@@ -516,6 +517,23 @@ 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[];
+
+       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;
+
+
+       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 bc6b631373ef4a4a317c61557dc3940dcbaa6440..2fb8560724a4ca7cb8313ab2543f1cd5528c4607 100644 (file)
--- a/arch/arm64/kernel/vmlinux.lds.S
+++ b/arch/arm64/kernel/vmlinux.lds.S
@@ -102,6 +102,7 @@ SECTIONS
                        *(.exception.text)
                        __exception_text_end = .;
                        IRQENTRY_TEXT
+                       ENTRY_TEXT
                        TEXT_TEXT
                        SCHED_TEXT
                        LOCK_TEXT