From 3f471126ee53feb5e9b210ea2f525ed3bb9b7a7f Mon Sep 17 00:00:00 2001 From: Nicolas Pitre Date: Sat, 14 Jan 2006 19:30:04 +0000 Subject: [ARM] 3262/4: allow ptraced syscalls to be overriden Patch from Nicolas Pitre This is needed by strace to properly handle the tracing of some system calls. It could be useful for other applications as well. Based on an earlier patch from Daniel Jacobowitz. Signed-off-by: Nicolas Pitre Signed-off-by: Daniel Jacobowitz Signed-off-by: Russell King --- arch/arm/kernel/ptrace.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) (limited to 'arch/arm/kernel/ptrace.c') diff --git a/arch/arm/kernel/ptrace.c b/arch/arm/kernel/ptrace.c index e591f72b..7b6256b 100644 --- a/arch/arm/kernel/ptrace.c +++ b/arch/arm/kernel/ptrace.c @@ -766,6 +766,11 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data) (unsigned long __user *) data); break; + case PTRACE_SET_SYSCALL: + ret = 0; + child->ptrace_message = data; + break; + default: ret = ptrace_request(child, request, addr, data); break; @@ -774,14 +779,14 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data) return ret; } -asmlinkage void syscall_trace(int why, struct pt_regs *regs) +asmlinkage int syscall_trace(int why, struct pt_regs *regs, int scno) { unsigned long ip; if (!test_thread_flag(TIF_SYSCALL_TRACE)) - return; + return scno; if (!(current->ptrace & PT_PTRACED)) - return; + return scno; /* * Save IP. IP is used to denote syscall entry/exit: @@ -790,6 +795,8 @@ asmlinkage void syscall_trace(int why, struct pt_regs *regs) ip = regs->ARM_ip; regs->ARM_ip = why; + current->ptrace_message = scno; + /* the 0x80 provides a way for the tracing parent to distinguish between a syscall stop and SIGTRAP delivery */ ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD) @@ -804,4 +811,6 @@ asmlinkage void syscall_trace(int why, struct pt_regs *regs) current->exit_code = 0; } regs->ARM_ip = ip; + + return current->ptrace_message; } -- cgit v1.1