ARM: 7455/1: audit: move syscall auditing until after ptrace SIGTRAP handling (5125430c) · Commits · 戴 / test

When auditing system calls on ARM, the audit code is called before notifying the parent process in the case that the current task is being ptraced. At this point, the parent (debugger) may choose to change the system call being issued via the SET_SYSCALL ptrace request, causing the wrong system call to be reported to the audit tools. This patch moves the audit calls after the ptrace SIGTRAP handling code in the syscall tracing implementation. Reviewed-by:

Catalin Marinas <catalin.marinas@arm.com> Signed-off-by:

Will Deacon <will.deacon@arm.com> Signed-off-by:

Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/kernel/ptrace.c

+9 −8

Original line number	Diff line number	Diff line
		@@ -911,14 +911,8 @@ asmlinkage int syscall_trace(int why, struct pt_regs *regs, int scno)
		{
		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;
		goto out_no_trace;

		current_thread_info()->syscall = scno;

		@@ -935,6 +929,13 @@ asmlinkage int syscall_trace(int why, struct pt_regs *regs, int scno)
		current_thread_info()->syscall = -1;

		regs->ARM_ip = ip;
		scno = current_thread_info()->syscall;

		return current_thread_info()->syscall;
		out_no_trace:
		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);
		return scno;
		}

Admin message