From 5d86456d3852cb95a38d2b23fe01cede54984ba5 Mon Sep 17 00:00:00 2001 From: Jeff Dike Date: Sun, 6 May 2007 14:51:24 -0700 Subject: [PATCH] uml: tidy fault code Tidying in preparation for the segfault register dumping patch which follows. void * pointers are changed to union uml_pt_regs *. This makes the types match reality, except in arch_fixup, which is changed to operate on a union uml_pt_regs. This fixes a bug in the call from segv_handler, which passes a union uml_pt_regs, to segv, which expects to pass a struct sigcontext to arch_fixup. Whitespace and other style fixes. There's also a errno printk fix. Signed-off-by: Jeff Dike Cc: Paolo 'Blaisorblade' Giarrusso Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/um/include/arch.h | 2 +- arch/um/include/kern_util.h | 2 +- arch/um/kernel/trap.c | 35 +++++++++++++++--------------- arch/um/os-Linux/skas/trap.c | 17 +++++++-------- arch/um/sys-i386/fault.c | 18 ++-------------- arch/um/sys-i386/signal.c | 41 +++++++++++++----------------------- arch/um/sys-x86_64/fault.c | 30 ++++++++++++++------------ arch/um/sys-x86_64/signal.c | 2 +- 8 files changed, 63 insertions(+), 84 deletions(-) diff --git a/arch/um/include/arch.h b/arch/um/include/arch.h index 8e11dd7c1a..10ad52daa8 100644 --- a/arch/um/include/arch.h +++ b/arch/um/include/arch.h @@ -9,7 +9,7 @@ #include "sysdep/ptrace.h" extern void arch_check_bugs(void); -extern int arch_fixup(unsigned long address, void *sc_ptr); +extern int arch_fixup(unsigned long address, union uml_pt_regs *regs); extern int arch_handle_signal(int sig, union uml_pt_regs *regs); #endif diff --git a/arch/um/include/kern_util.h b/arch/um/include/kern_util.h index ae434a9b40..092a284155 100644 --- a/arch/um/include/kern_util.h +++ b/arch/um/include/kern_util.h @@ -44,7 +44,7 @@ extern unsigned long alloc_stack(int order, int atomic); extern int do_signal(void); extern int is_stack_fault(unsigned long sp); extern unsigned long segv(struct faultinfo fi, unsigned long ip, - int is_user, void *sc); + int is_user, union uml_pt_regs *regs); extern int handle_page_fault(unsigned long address, unsigned long ip, int is_write, int is_user, int *code_out); extern void syscall_ready(void); diff --git a/arch/um/kernel/trap.c b/arch/um/kernel/trap.c index 2de81d4d9b..c3e62e634c 100644 --- a/arch/um/kernel/trap.c +++ b/arch/um/kernel/trap.c @@ -72,8 +72,8 @@ good_area: goto out; /* Don't require VM_READ|VM_EXEC for write faults! */ - if(!is_write && !(vma->vm_flags & (VM_READ | VM_EXEC))) - goto out; + if(!is_write && !(vma->vm_flags & (VM_READ | VM_EXEC))) + goto out; do { survive: @@ -157,18 +157,19 @@ static void segv_handler(int sig, union uml_pt_regs *regs) * the info in the regs. A pointer to the info then would * give us bad data! */ -unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user, void *sc) +unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user, + union uml_pt_regs *regs) { struct siginfo si; void *catcher; int err; - int is_write = FAULT_WRITE(fi); - unsigned long address = FAULT_ADDRESS(fi); + int is_write = FAULT_WRITE(fi); + unsigned long address = FAULT_ADDRESS(fi); - if(!is_user && (address >= start_vm) && (address < end_vm)){ - flush_tlb_kernel_vm(); - return(0); - } + if(!is_user && (address >= start_vm) && (address < end_vm)){ + flush_tlb_kernel_vm(); + return 0; + } else if(current->mm == NULL) panic("Segfault with no mm"); @@ -183,17 +184,17 @@ unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user, void *sc) catcher = current->thread.fault_catcher; if(!err) - return(0); + return 0; else if(catcher != NULL){ current->thread.fault_addr = (void *) address; do_longjmp(catcher, 1); } else if(current->thread.fault_addr != NULL) panic("fault_addr set but no fault catcher"); - else if(!is_user && arch_fixup(ip, sc)) - return(0); + else if(!is_user && arch_fixup(ip, regs)) + return 0; - if(!is_user) + if(!is_user) panic("Kernel mode fault at addr 0x%lx, ip 0x%lx", address, ip); @@ -202,7 +203,7 @@ unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user, void *sc) si.si_errno = 0; si.si_code = BUS_ADRERR; si.si_addr = (void __user *)address; - current->thread.arch.faultinfo = fi; + current->thread.arch.faultinfo = fi; force_sig_info(SIGBUS, &si, current); } else if (err == -ENOMEM) { printk("VM: killing process %s\n", current->comm); @@ -211,10 +212,10 @@ unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user, void *sc) BUG_ON(err != -EFAULT); si.si_signo = SIGSEGV; si.si_addr = (void __user *) address; - current->thread.arch.faultinfo = fi; + current->thread.arch.faultinfo = fi; force_sig_info(SIGSEGV, &si, current); } - return(0); + return 0; } void relay_signal(int sig, union uml_pt_regs *regs) @@ -229,7 +230,7 @@ void relay_signal(int sig, union uml_pt_regs *regs) panic("Kernel mode signal %d", sig); } - current->thread.arch.faultinfo = *UPT_FAULTINFO(regs); + current->thread.arch.faultinfo = *UPT_FAULTINFO(regs); force_sig(sig, current); } diff --git a/arch/um/os-Linux/skas/trap.c b/arch/um/os-Linux/skas/trap.c index f104427d2c..6a20d08caf 100644 --- a/arch/um/os-Linux/skas/trap.c +++ b/arch/um/os-Linux/skas/trap.c @@ -18,10 +18,9 @@ void sig_handler_common_skas(int sig, void *sc_ptr) { struct sigcontext *sc = sc_ptr; - struct skas_regs *r; + union uml_pt_regs *r; void (*handler)(int, union uml_pt_regs *); - int save_errno = errno; - int save_user; + int save_user, save_errno = errno; /* This is done because to allow SIGSEGV to be delivered inside a SEGV * handler. This can happen in copy_user, and if SEGV is disabled, @@ -31,13 +30,13 @@ void sig_handler_common_skas(int sig, void *sc_ptr) if(sig == SIGSEGV) change_sig(SIGSEGV, 1); - r = &TASK_REGS(get_current())->skas; - save_user = r->is_user; - r->is_user = 0; + r = TASK_REGS(get_current()); + save_user = r->skas.is_user; + r->skas.is_user = 0; if ( sig == SIGFPE || sig == SIGSEGV || sig == SIGBUS || sig == SIGILL || sig == SIGTRAP ) { - GET_FAULTINFO_FROM_SC(r->faultinfo, sc); + GET_FAULTINFO_FROM_SC(r->skas.faultinfo, sc); } change_sig(SIGUSR1, 1); @@ -49,10 +48,10 @@ void sig_handler_common_skas(int sig, void *sc_ptr) sig != SIGVTALRM && sig != SIGALRM) unblock_signals(); - handler(sig, (union uml_pt_regs *) r); + handler(sig, r); errno = save_errno; - r->is_user = save_user; + r->skas.is_user = save_user; } extern int ptrace_faultinfo; diff --git a/arch/um/sys-i386/fault.c b/arch/um/sys-i386/fault.c index d0bbcdfdb5..745b4fd49e 100644 --- a/arch/um/sys-i386/fault.c +++ b/arch/um/sys-i386/fault.c @@ -3,9 +3,7 @@ * Licensed under the GPL */ -#include #include "sysdep/ptrace.h" -#include "sysdep/sigcontext.h" /* These two are from asm-um/uaccess.h and linux/module.h, check them. */ struct exception_table_entry @@ -17,26 +15,14 @@ struct exception_table_entry const struct exception_table_entry *search_exception_tables(unsigned long add); /* Compare this to arch/i386/mm/extable.c:fixup_exception() */ -int arch_fixup(unsigned long address, void *sc_ptr) +int arch_fixup(unsigned long address, union uml_pt_regs *regs) { - struct sigcontext *sc = sc_ptr; const struct exception_table_entry *fixup; fixup = search_exception_tables(address); if(fixup != 0){ - sc->eip = fixup->fixup; + UPT_IP(regs) = fixup->fixup; return(1); } return(0); } - -/* - * Overrides for Emacs so that we follow Linus's tabbing style. - * Emacs will notice this stuff at the end of the file and automatically - * adjust the settings for this buffer only. This must remain at the end - * of the file. - * --------------------------------------------------------------------------- - * Local variables: - * c-file-style: "linux" - * End: - */ diff --git a/arch/um/sys-i386/signal.c b/arch/um/sys-i386/signal.c index 3f6acd6677..42ecf8e8ad 100644 --- a/arch/um/sys-i386/signal.c +++ b/arch/um/sys-i386/signal.c @@ -28,7 +28,7 @@ static int copy_sc_from_user_skas(struct pt_regs *regs, err = copy_from_user(&sc, from, sizeof(sc)); err |= copy_from_user(fpregs, sc.fpstate, sizeof(fpregs)); if(err) - return(err); + return err; REGS_GS(regs->regs.skas.regs) = sc.gs; REGS_FS(regs->regs.skas.regs) = sc.fs; @@ -50,11 +50,11 @@ static int copy_sc_from_user_skas(struct pt_regs *regs, err = restore_fp_registers(userspace_pid[0], fpregs); if(err < 0){ printk("copy_sc_from_user_skas - PTRACE_SETFPREGS failed, " - "errno = %d\n", err); - return(1); + "errno = %d\n", -err); + return err; } - return(0); + return 0; } int copy_sc_to_user_skas(struct sigcontext __user *to, struct _fpstate __user *to_fp, @@ -90,16 +90,16 @@ int copy_sc_to_user_skas(struct sigcontext __user *to, struct _fpstate __user *t if(err < 0){ printk("copy_sc_to_user_skas - PTRACE_GETFPREGS failed, " "errno = %d\n", err); - return(1); + return 1; } to_fp = (to_fp ? to_fp : (struct _fpstate __user *) (to + 1)); sc.fpstate = to_fp; if(err) - return(err); + return err; - return(copy_to_user(to, &sc, sizeof(sc)) || - copy_to_user(to_fp, fpregs, sizeof(fpregs))); + return copy_to_user(to, &sc, sizeof(sc)) || + copy_to_user(to_fp, fpregs, sizeof(fpregs)); } #endif @@ -129,7 +129,7 @@ int copy_sc_from_user_tt(struct sigcontext *to, struct sigcontext __user *from, to->fpstate = to_fp; if(to_fp != NULL) err |= copy_from_user(to_fp, from_fp, fpsize); - return(err); + return err; } int copy_sc_to_user_tt(struct sigcontext __user *to, struct _fpstate __user *fp, @@ -164,15 +164,15 @@ static int copy_sc_from_user(struct pt_regs *to, void __user *from) ret = CHOOSE_MODE(copy_sc_from_user_tt(UPT_SC(&to->regs), from, sizeof(struct _fpstate)), copy_sc_from_user_skas(to, from)); - return(ret); + return ret; } static int copy_sc_to_user(struct sigcontext __user *to, struct _fpstate __user *fp, struct pt_regs *from, unsigned long sp) { - return(CHOOSE_MODE(copy_sc_to_user_tt(to, fp, UPT_SC(&from->regs), + return CHOOSE_MODE(copy_sc_to_user_tt(to, fp, UPT_SC(&from->regs), sizeof(*fp), sp), - copy_sc_to_user_skas(to, fp, from, sp))); + copy_sc_to_user_skas(to, fp, from, sp)); } static int copy_ucontext_to_user(struct ucontext __user *uc, struct _fpstate __user *fp, @@ -185,7 +185,7 @@ static int copy_ucontext_to_user(struct ucontext __user *uc, struct _fpstate __u err |= put_user(current->sas_ss_size, &uc->uc_stack.ss_size); err |= copy_sc_to_user(&uc->uc_mcontext, fp, ¤t->thread.regs, sp); err |= copy_to_user(&uc->uc_sigmask, set, sizeof(*set)); - return(err); + return err; } struct sigframe @@ -359,7 +359,7 @@ long sys_sigreturn(struct pt_regs regs) /* Avoid ERESTART handling */ PT_REGS_SYSCALL_NR(¤t->thread.regs) = -1; - return(PT_REGS_SYSCALL_RET(¤t->thread.regs)); + return PT_REGS_SYSCALL_RET(¤t->thread.regs); segfault: force_sig(SIGSEGV, current); @@ -389,20 +389,9 @@ long sys_rt_sigreturn(struct pt_regs regs) /* Avoid ERESTART handling */ PT_REGS_SYSCALL_NR(¤t->thread.regs) = -1; - return(PT_REGS_SYSCALL_RET(¤t->thread.regs)); + return PT_REGS_SYSCALL_RET(¤t->thread.regs); segfault: force_sig(SIGSEGV, current); return 0; } - -/* - * Overrides for Emacs so that we follow Linus's tabbing style. - * Emacs will notice this stuff at the end of the file and automatically - * adjust the settings for this buffer only. This must remain at the end - * of the file. - * --------------------------------------------------------------------------- - * Local variables: - * c-file-style: "linux" - * End: - */ diff --git a/arch/um/sys-x86_64/fault.c b/arch/um/sys-x86_64/fault.c index cee1513c5c..4636b1465b 100644 --- a/arch/um/sys-x86_64/fault.c +++ b/arch/um/sys-x86_64/fault.c @@ -4,20 +4,24 @@ * Licensed under the GPL */ -#include "user.h" +#include "sysdep/ptrace.h" -int arch_fixup(unsigned long address, void *sc_ptr) +/* These two are from asm-um/uaccess.h and linux/module.h, check them. */ +struct exception_table_entry { - /* XXX search_exception_tables() */ + unsigned long insn; + unsigned long fixup; +}; + +const struct exception_table_entry *search_exception_tables(unsigned long add); +int arch_fixup(unsigned long address, union uml_pt_regs *regs) +{ + const struct exception_table_entry *fixup; + + fixup = search_exception_tables(address); + if(fixup != 0){ + UPT_IP(regs) = fixup->fixup; + return(1); + } return(0); } - -/* Overrides for Emacs so that we follow Linus's tabbing style. - * Emacs will notice this stuff at the end of the file and automatically - * adjust the settings for this buffer only. This must remain at the end - * of the file. - * --------------------------------------------------------------------------- - * Local variables: - * c-file-style: "linux" - * End: - */ diff --git a/arch/um/sys-x86_64/signal.c b/arch/um/sys-x86_64/signal.c index af2f017617..0680062135 100644 --- a/arch/um/sys-x86_64/signal.c +++ b/arch/um/sys-x86_64/signal.c @@ -51,7 +51,7 @@ static int copy_sc_from_user_skas(struct pt_regs *regs, #undef GETREG - return(err); + return err; } int copy_sc_to_user_skas(struct sigcontext __user *to, -- 2.39.5