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-rw-r--r--arch/arm/kernel/ptrace.c69
1 files changed, 54 insertions, 15 deletions
diff --git a/arch/arm/kernel/ptrace.c b/arch/arm/kernel/ptrace.c
index 14e38261cd3..03deeffd9f6 100644
--- a/arch/arm/kernel/ptrace.c
+++ b/arch/arm/kernel/ptrace.c
@@ -25,10 +25,14 @@
#include <linux/regset.h>
#include <linux/audit.h>
#include <linux/tracehook.h>
+#include <linux/unistd.h>
#include <asm/pgtable.h>
#include <asm/traps.h>
+#define CREATE_TRACE_POINTS
+#include <trace/events/syscalls.h>
+
#define REG_PC 15
#define REG_PSR 16
/*
@@ -907,34 +911,69 @@ long arch_ptrace(struct task_struct *child, long request,
return ret;
}
-asmlinkage int syscall_trace(int why, struct pt_regs *regs, int scno)
+enum ptrace_syscall_dir {
+ PTRACE_SYSCALL_ENTER = 0,
+ PTRACE_SYSCALL_EXIT,
+};
+
+static int tracehook_report_syscall(struct pt_regs *regs,
+ enum ptrace_syscall_dir dir)
{
unsigned long ip;
- if (why)
- audit_syscall_exit(regs);
- else
- audit_syscall_entry(AUDIT_ARCH_ARM, scno, regs->ARM_r0,
- regs->ARM_r1, regs->ARM_r2, regs->ARM_r3);
-
- if (!test_thread_flag(TIF_SYSCALL_TRACE))
- return scno;
-
- current_thread_info()->syscall = scno;
-
/*
* IP is used to denote syscall entry/exit:
* IP = 0 -> entry, =1 -> exit
*/
ip = regs->ARM_ip;
- regs->ARM_ip = why;
+ regs->ARM_ip = dir;
- if (why)
+ if (dir == PTRACE_SYSCALL_EXIT)
tracehook_report_syscall_exit(regs, 0);
else if (tracehook_report_syscall_entry(regs))
current_thread_info()->syscall = -1;
regs->ARM_ip = ip;
-
return current_thread_info()->syscall;
}
+
+asmlinkage int syscall_trace_enter(struct pt_regs *regs, int scno)
+{
+ current_thread_info()->syscall = scno;
+
+ /* Do the secure computing check first; failures should be fast. */
+ if (secure_computing(scno) == -1)
+ return -1;
+
+ if (test_thread_flag(TIF_SYSCALL_TRACE))
+ scno = tracehook_report_syscall(regs, PTRACE_SYSCALL_ENTER);
+
+ if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
+ trace_sys_enter(regs, scno);
+
+ audit_syscall_entry(AUDIT_ARCH_ARM, scno, regs->ARM_r0, regs->ARM_r1,
+ regs->ARM_r2, regs->ARM_r3);
+
+ return scno;
+}
+
+asmlinkage void syscall_trace_exit(struct pt_regs *regs)
+{
+ /*
+ * Audit the syscall before anything else, as a debugger may
+ * come in and change the current registers.
+ */
+ audit_syscall_exit(regs);
+
+ /*
+ * Note that we haven't updated the ->syscall field for the
+ * current thread. This isn't a problem because it will have
+ * been set on syscall entry and there hasn't been an opportunity
+ * for a PTRACE_SET_SYSCALL since then.
+ */
+ if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
+ trace_sys_exit(regs, regs_return_value(regs));
+
+ if (test_thread_flag(TIF_SYSCALL_TRACE))
+ tracehook_report_syscall(regs, PTRACE_SYSCALL_EXIT);
+}