um: Store syscall number after syscall_trace_enter() (1d80f0cd) · Commits · 戴 / test

arch/um/include/shared/os.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -274,6 +274,7 @@ extern void initial_thread_cb_skas(void (proc)(void ),
		void *arg);
		extern void halt_skas(void);
		extern void reboot_skas(void);
		extern int get_syscall(struct uml_pt_regs *regs);

		/* irq.c */
		extern int os_waiting_for_events(struct irq_fd *active_fds);

+3 −10

Original line number	Diff line number	Diff line
		@@ -8,6 +8,7 @@
		#include <kern_util.h>
		#include <sysdep/ptrace.h>
		#include <sysdep/syscalls.h>
		#include <os.h>

		extern int syscall_table_size;
		#define NR_SYSCALLS (syscall_table_size / sizeof(void *))
		@@ -23,16 +24,8 @@ void handle_syscall(struct uml_pt_regs *r)
		goto out;
		}

		/*
		* This should go in the declaration of syscall, but when I do that,
		* strace -f -c bash -c 'ls ; ls' breaks, sometimes not tracing
		* children at all, sometimes hanging when bash doesn't see the first
		* ls exit.
		* The assembly looks functionally the same to me. This is
		* gcc version 4.0.1 20050727 (Red Hat 4.0.1-5)
		* in case it's a compiler bug.
		*/
		syscall = UPT_SYSCALL_NR(r);
		syscall = get_syscall(r);

		if ((syscall >= NR_SYSCALLS) \|\| (syscall < 0))
		result = -ENOSYS;
		else result = EXECUTE_SYSCALL(syscall, regs);

+7 −3

Original line number	Diff line number	Diff line
		@@ -137,9 +137,6 @@ static void handle_trap(int pid, struct uml_pt_regs *regs,
		if ((UPT_IP(regs) >= STUB_START) && (UPT_IP(regs) < STUB_END))
		fatal_sigsegv();

		/* Mark this as a syscall */
		UPT_SYSCALL_NR(regs) = PT_SYSCALL_NR(regs->gp);

		if (!local_using_sysemu)
		{
		err = ptrace(PTRACE_POKEUSER, pid, PT_SYSCALL_NR_OFFSET,
		@@ -174,6 +171,13 @@ static void handle_trap(int pid, struct uml_pt_regs *regs,
		handle_syscall(regs);
		}

		int get_syscall(struct uml_pt_regs *regs)
		{
		UPT_SYSCALL_NR(regs) = PT_SYSCALL_NR(regs->gp);

		return UPT_SYSCALL_NR(regs);
		}

		extern char __syscall_stub_start[];

		static int userspace_tramp(void *stack)