Commit 5d86456d authored by Jeff Dike's avatar Jeff Dike Committed by Linus Torvalds
Browse files

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: default avatarJeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent ccdddb57
......@@ -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
......@@ -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);
......
......@@ -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);
}
......
......@@ -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;
......
......@@ -3,9 +3,7 @@
* Licensed under the GPL
*/
#include <signal.h>
#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:
*/
......@@ -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, &current->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(&current->thread.regs) = -1;
return(PT_REGS_SYSCALL_RET(&current->thread.regs));
return PT_REGS_SYSCALL_RET(&current->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(&current->thread.regs) = -1;
return(PT_REGS_SYSCALL_RET(&current->thread.regs));
return PT_REGS_SYSCALL_RET(&current->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:
*/
......@@ -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:
*/
......@@ -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,
......
Supports Markdown
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment