From: Steven Rostedt <[email protected]> task_current_syscall() has a single user that passes in 6 for maxargs, which is the maximum arguments that can be used to get system calls from syscall_get_arguments(). Instead of passing in a number of arguments to grab, just get 6 arguments. The args argument even specifies that it's an array of 6 items.
This will also allow changing syscall_get_arguments() to not get a variable number of arguments, but always grab 6. Signed-off-by: Steven Rostedt <[email protected]> --- fs/proc/base.c | 2 +- include/linux/ptrace.h | 4 ++-- lib/syscall.c | 22 ++++++++-------------- 3 files changed, 11 insertions(+), 17 deletions(-) diff --git a/fs/proc/base.c b/fs/proc/base.c index 8e654468ab67..25cd58bd7236 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -650,7 +650,7 @@ static int proc_pid_syscall(struct seq_file *m, struct pid_namespace *ns, if (res) return res; - if (task_current_syscall(task, &nr, args, 6, &sp, &pc)) + if (task_current_syscall(task, &nr, args, &sp, &pc)) seq_puts(m, "running\n"); else if (nr < 0) seq_printf(m, "%ld 0x%lx 0x%lx\n", nr, sp, pc); diff --git a/include/linux/ptrace.h b/include/linux/ptrace.h index 504c98a278d4..8af5226d2ee6 100644 --- a/include/linux/ptrace.h +++ b/include/linux/ptrace.h @@ -403,7 +403,7 @@ static inline void user_single_step_siginfo(struct task_struct *tsk, #endif extern int task_current_syscall(struct task_struct *target, long *callno, - unsigned long args[6], unsigned int maxargs, - unsigned long *sp, unsigned long *pc); + unsigned long args[6], unsigned long *sp, + unsigned long *pc); #endif diff --git a/lib/syscall.c b/lib/syscall.c index 63239e097b13..cbd376c66bbc 100644 --- a/lib/syscall.c +++ b/lib/syscall.c @@ -4,8 +4,8 @@ #include <asm/syscall.h> static int collect_syscall(struct task_struct *target, long *callno, - unsigned long args[6], unsigned int maxargs, - unsigned long *sp, unsigned long *pc) + unsigned long args[6], unsigned long *sp, + unsigned long *pc) { struct pt_regs *regs; @@ -25,8 +25,8 @@ static int collect_syscall(struct task_struct *target, long *callno, *pc = instruction_pointer(regs); *callno = syscall_get_nr(target, regs); - if (*callno != -1L && maxargs > 0) - syscall_get_arguments(target, regs, 0, maxargs, args); + if (*callno != -1L) + syscall_get_arguments(target, regs, 0, 6, args); put_task_stack(target); return 0; @@ -37,7 +37,6 @@ static int collect_syscall(struct task_struct *target, long *callno, * @target: thread to examine * @callno: filled with system call number or -1 * @args: filled with @maxargs system call arguments - * @maxargs: number of elements in @args to fill * @sp: filled with user stack pointer * @pc: filled with user PC * @@ -55,21 +54,16 @@ static int collect_syscall(struct task_struct *target, long *callno, * get() calls as long as we're sure @target won't return to user mode. * * Returns -%EAGAIN if @target does not remain blocked. - * - * Returns -%EINVAL if @maxargs is too large (maximum is six). */ int task_current_syscall(struct task_struct *target, long *callno, - unsigned long args[6], unsigned int maxargs, - unsigned long *sp, unsigned long *pc) + unsigned long args[6], unsigned long *sp, + unsigned long *pc) { long state; unsigned long ncsw; - if (unlikely(maxargs > 6)) - return -EINVAL; - if (target == current) - return collect_syscall(target, callno, args, maxargs, sp, pc); + return collect_syscall(target, callno, args, sp, pc); state = target->state; if (unlikely(!state)) @@ -77,7 +71,7 @@ int task_current_syscall(struct task_struct *target, long *callno, ncsw = wait_task_inactive(target, state); if (unlikely(!ncsw) || - unlikely(collect_syscall(target, callno, args, maxargs, sp, pc)) || + unlikely(collect_syscall(target, callno, args, sp, pc)) || unlikely(wait_task_inactive(target, state) != ncsw)) return -EAGAIN; -- 2.9.3
