From efc463adbccf709c5dbaf6cfbf84b7e94b62810a Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Mon, 16 Apr 2018 14:18:26 -0500 Subject: signal: Simplify tracehook_report_syscall_exit Replace user_single_step_siginfo with user_single_step_report that allocates siginfo structure on the stack and sends it. This allows tracehook_report_syscall_exit to become a simple if statement that calls user_single_step_report or ptrace_report_syscall depending on the value of step. Update the default helper function now called user_single_step_report to explicitly set si_code to SI_USER and to set si_uid and si_pid to 0. The default helper has always been doing this (using memset) but it was far from obvious. The powerpc helper can now just call force_sig_fault. The x86 helper can now just call send_sigtrap. Unfortunately the default implementation of user_single_step_report can not use force_sig_fault as it does not use a SIGTRAP si_code. So it has to carefully setup the siginfo and use use force_sig_info. The net result is code that is easier to understand and simpler to maintain. Ref: 85ec7fd9f8e5 ("ptrace: introduce user_single_step_siginfo() helper") Reviewed-by: Thomas Gleixner Signed-off-by: "Eric W. Biederman" --- include/linux/ptrace.h | 17 +++++++++++------ include/linux/tracehook.h | 13 ++++--------- 2 files changed, 15 insertions(+), 15 deletions(-) (limited to 'include') diff --git a/include/linux/ptrace.h b/include/linux/ptrace.h index 4f36431c380b..1de2235511c8 100644 --- a/include/linux/ptrace.h +++ b/include/linux/ptrace.h @@ -336,14 +336,19 @@ static inline void user_enable_block_step(struct task_struct *task) extern void user_enable_block_step(struct task_struct *); #endif /* arch_has_block_step */ -#ifdef ARCH_HAS_USER_SINGLE_STEP_INFO -extern void user_single_step_siginfo(struct task_struct *tsk, - struct pt_regs *regs, siginfo_t *info); +#ifdef ARCH_HAS_USER_SINGLE_STEP_REPORT +extern void user_single_step_report(struct pt_regs *regs); #else -static inline void user_single_step_siginfo(struct task_struct *tsk, - struct pt_regs *regs, siginfo_t *info) +static inline void user_single_step_report(struct pt_regs *regs) { - info->si_signo = SIGTRAP; + siginfo_t info; + clear_siginfo(&info); + info.si_signo = SIGTRAP; + info.si_errno = 0; + info.si_code = SI_USER; + info.si_pid = 0; + info.si_uid = 0; + force_sig_info(info.si_signo, &info, current); } #endif diff --git a/include/linux/tracehook.h b/include/linux/tracehook.h index 05589a3e37f4..40b0b4c1bf7b 100644 --- a/include/linux/tracehook.h +++ b/include/linux/tracehook.h @@ -123,15 +123,10 @@ static inline __must_check int tracehook_report_syscall_entry( */ static inline void tracehook_report_syscall_exit(struct pt_regs *regs, int step) { - if (step) { - siginfo_t info; - clear_siginfo(&info); - user_single_step_siginfo(current, regs, &info); - force_sig_info(SIGTRAP, &info, current); - return; - } - - ptrace_report_syscall(regs); + if (step) + user_single_step_report(regs); + else + ptrace_report_syscall(regs); } /** -- cgit