From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Eric W. Biederman" Subject: [REVIEW][PATCH 20/22] signal/um: Use force_sig_fault where appropriate Date: Fri, 20 Apr 2018 09:38:09 -0500 Message-ID: <20180420143811.9994-20-ebiederm@xmission.com> References: <87604mhrnb.fsf@xmission.com> Return-path: In-Reply-To: <87604mhrnb.fsf@xmission.com> Sender: linux-kernel-owner@vger.kernel.org To: linux-arch@vger.kernel.org Cc: linux-kernel@vger.kernel.org, "Eric W. Biederman" , Jeff Dike , Richard Weinberger , user-mode-linux-devel@lists.sourceforge.net List-Id: linux-arch.vger.kernel.org Filling in struct siginfo before calling force_sig_info a tedious and error prone process, where once in a great while the wrong fields are filled out, and siginfo has been inconsistently cleared. Simplify this process by using the helper force_sig_fault. Which takes as a parameters all of the information it needs, ensures all of the fiddly bits of filling in struct siginfo are done properly and then calls force_sig_info. In short about a 5 line reduction in code for every time force_sig_info is called, which makes the calling function clearer. Cc: Jeff Dike Cc: Richard Weinberger Cc: user-mode-linux-devel@lists.sourceforge.net Signed-off-by: "Eric W. Biederman" --- arch/um/kernel/ptrace.c | 13 +++---------- arch/um/kernel/trap.c | 26 ++++++++------------------ 2 files changed, 11 insertions(+), 28 deletions(-) diff --git a/arch/um/kernel/ptrace.c b/arch/um/kernel/ptrace.c index bc2a516c190f..1a1d88a4d940 100644 --- a/arch/um/kernel/ptrace.c +++ b/arch/um/kernel/ptrace.c @@ -115,17 +115,10 @@ long arch_ptrace(struct task_struct *child, long request, static void send_sigtrap(struct task_struct *tsk, struct uml_pt_regs *regs, int error_code) { - struct siginfo info; - - memset(&info, 0, sizeof(info)); - info.si_signo = SIGTRAP; - info.si_code = TRAP_BRKPT; - - /* User-mode eip? */ - info.si_addr = UPT_IS_USER(regs) ? (void __user *) UPT_IP(regs) : NULL; - /* Send us the fake SIGTRAP */ - force_sig_info(SIGTRAP, &info, tsk); + force_sig_fault(SIGTRAP, TRAP_BRKPT, + /* User-mode eip? */ + UPT_IS_USER(regs) ? (void __user *) UPT_IP(regs) : NULL, tsk); } /* diff --git a/arch/um/kernel/trap.c b/arch/um/kernel/trap.c index 5f0ff17cd790..48b70dcb6963 100644 --- a/arch/um/kernel/trap.c +++ b/arch/um/kernel/trap.c @@ -162,14 +162,9 @@ static void show_segv_info(struct uml_pt_regs *regs) static void bad_segv(struct faultinfo fi, unsigned long ip) { - struct siginfo si; - - clear_siginfo(&si); - si.si_signo = SIGSEGV; - si.si_code = SEGV_ACCERR; - si.si_addr = (void __user *) FAULT_ADDRESS(fi); current->thread.arch.faultinfo = fi; - force_sig_info(SIGSEGV, &si, current); + force_sig_fault(SIGSEGV, SEGV_ACCERR, (void __user *) FAULT_ADDRESS(fi), + current); } void fatal_sigsegv(void) @@ -215,13 +210,12 @@ void segv_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs) unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user, struct uml_pt_regs *regs) { - struct siginfo si; jmp_buf *catcher; + int si_code; int err; int is_write = FAULT_WRITE(fi); unsigned long address = FAULT_ADDRESS(fi); - clear_siginfo(&si); if (!is_user && regs) current->thread.segv_regs = container_of(regs, struct pt_regs, regs); @@ -241,7 +235,7 @@ unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user, if (SEGV_IS_FIXABLE(&fi)) err = handle_page_fault(address, ip, is_write, is_user, - &si.si_code); + &si_code); else { err = -EFAULT; /* @@ -273,18 +267,14 @@ unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user, show_segv_info(regs); if (err == -EACCES) { - si.si_signo = SIGBUS; - si.si_errno = 0; - si.si_code = BUS_ADRERR; - si.si_addr = (void __user *)address; current->thread.arch.faultinfo = fi; - force_sig_info(SIGBUS, &si, current); + force_sig_fault(SIGBUS, BUS_ADRERR, (void __user *)address, + current); } else { BUG_ON(err != -EFAULT); - si.si_signo = SIGSEGV; - si.si_addr = (void __user *) address; current->thread.arch.faultinfo = fi; - force_sig_info(SIGSEGV, &si, current); + force_sig_fault(SIGSEGV, si_code, (void __user *) address, + current); } out: -- 2.14.1 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from out02.mta.xmission.com ([166.70.13.232]:44838 "EHLO out02.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755191AbeDTOqD (ORCPT ); Fri, 20 Apr 2018 10:46:03 -0400 From: "Eric W. Biederman" Date: Fri, 20 Apr 2018 09:38:09 -0500 Message-ID: <20180420143811.9994-20-ebiederm@xmission.com> In-Reply-To: <87604mhrnb.fsf@xmission.com> References: <87604mhrnb.fsf@xmission.com> Subject: [REVIEW][PATCH 20/22] signal/um: Use force_sig_fault where appropriate Sender: linux-arch-owner@vger.kernel.org List-ID: To: linux-arch@vger.kernel.org Cc: linux-kernel@vger.kernel.org, "Eric W. Biederman" , Jeff Dike , Richard Weinberger , user-mode-linux-devel@lists.sourceforge.net Message-ID: <20180420143809.vpSEHXiHQ7wyAZb9IA8Pdeor4xN51pcK3m6Sv7NOHM8@z> Filling in struct siginfo before calling force_sig_info a tedious and error prone process, where once in a great while the wrong fields are filled out, and siginfo has been inconsistently cleared. Simplify this process by using the helper force_sig_fault. Which takes as a parameters all of the information it needs, ensures all of the fiddly bits of filling in struct siginfo are done properly and then calls force_sig_info. In short about a 5 line reduction in code for every time force_sig_info is called, which makes the calling function clearer. Cc: Jeff Dike Cc: Richard Weinberger Cc: user-mode-linux-devel@lists.sourceforge.net Signed-off-by: "Eric W. Biederman" --- arch/um/kernel/ptrace.c | 13 +++---------- arch/um/kernel/trap.c | 26 ++++++++------------------ 2 files changed, 11 insertions(+), 28 deletions(-) diff --git a/arch/um/kernel/ptrace.c b/arch/um/kernel/ptrace.c index bc2a516c190f..1a1d88a4d940 100644 --- a/arch/um/kernel/ptrace.c +++ b/arch/um/kernel/ptrace.c @@ -115,17 +115,10 @@ long arch_ptrace(struct task_struct *child, long request, static void send_sigtrap(struct task_struct *tsk, struct uml_pt_regs *regs, int error_code) { - struct siginfo info; - - memset(&info, 0, sizeof(info)); - info.si_signo = SIGTRAP; - info.si_code = TRAP_BRKPT; - - /* User-mode eip? */ - info.si_addr = UPT_IS_USER(regs) ? (void __user *) UPT_IP(regs) : NULL; - /* Send us the fake SIGTRAP */ - force_sig_info(SIGTRAP, &info, tsk); + force_sig_fault(SIGTRAP, TRAP_BRKPT, + /* User-mode eip? */ + UPT_IS_USER(regs) ? (void __user *) UPT_IP(regs) : NULL, tsk); } /* diff --git a/arch/um/kernel/trap.c b/arch/um/kernel/trap.c index 5f0ff17cd790..48b70dcb6963 100644 --- a/arch/um/kernel/trap.c +++ b/arch/um/kernel/trap.c @@ -162,14 +162,9 @@ static void show_segv_info(struct uml_pt_regs *regs) static void bad_segv(struct faultinfo fi, unsigned long ip) { - struct siginfo si; - - clear_siginfo(&si); - si.si_signo = SIGSEGV; - si.si_code = SEGV_ACCERR; - si.si_addr = (void __user *) FAULT_ADDRESS(fi); current->thread.arch.faultinfo = fi; - force_sig_info(SIGSEGV, &si, current); + force_sig_fault(SIGSEGV, SEGV_ACCERR, (void __user *) FAULT_ADDRESS(fi), + current); } void fatal_sigsegv(void) @@ -215,13 +210,12 @@ void segv_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs) unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user, struct uml_pt_regs *regs) { - struct siginfo si; jmp_buf *catcher; + int si_code; int err; int is_write = FAULT_WRITE(fi); unsigned long address = FAULT_ADDRESS(fi); - clear_siginfo(&si); if (!is_user && regs) current->thread.segv_regs = container_of(regs, struct pt_regs, regs); @@ -241,7 +235,7 @@ unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user, if (SEGV_IS_FIXABLE(&fi)) err = handle_page_fault(address, ip, is_write, is_user, - &si.si_code); + &si_code); else { err = -EFAULT; /* @@ -273,18 +267,14 @@ unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user, show_segv_info(regs); if (err == -EACCES) { - si.si_signo = SIGBUS; - si.si_errno = 0; - si.si_code = BUS_ADRERR; - si.si_addr = (void __user *)address; current->thread.arch.faultinfo = fi; - force_sig_info(SIGBUS, &si, current); + force_sig_fault(SIGBUS, BUS_ADRERR, (void __user *)address, + current); } else { BUG_ON(err != -EFAULT); - si.si_signo = SIGSEGV; - si.si_addr = (void __user *) address; current->thread.arch.faultinfo = fi; - force_sig_info(SIGSEGV, &si, current); + force_sig_fault(SIGSEGV, si_code, (void __user *) address, + current); } out: -- 2.14.1