freebsd-dev/usr.bin/truss/i386-linux.c
John Baldwin 287b96dd25 Add handling for non-native error values to libsysdecode.
Add two new functions, sysdecode_abi_to_freebsd_errno() and
sysdecode_freebsd_to_abi_errno(), which convert errno values between
the native FreeBSD ABI and other supported ABIs. Note that the
mappings are not necessarily perfect meaning in some cases multiple
errors in one ABI might map to a single error in another ABI. In that
case, the reverse mapping will return one of the errors that maps, but
which error is non-deterministic.

Change truss to always report the raw error value to the user but
use libsysdecode to map it to a native errno value that can be used
with strerror() to generate a description. Previously truss reported
the "converted" error value. Now the user will always see the exact
error value that the application sees.

Change kdump to report the truly raw error value to the user. Previously
kdump would report the absolute value of the raw error value (so for
Linux binaries it didn't output the FreeBSD error value, but the positive
value of the Linux error). Now it reports the real (i.e. negative) error
value for Linux binaries. Also, use libsysdecode to convert the native
FreeBSD error reported in the ktrace record to the raw error used by the
ABI. This means that the Linux ABI can now be handled directly in
ktrsysret() and removes the need for linux_ktrsysret().

Reviewed by:	bdrewery, kib
Helpful notes:	wblock (manpage)
Differential Revision:	https://reviews.freebsd.org/D5314
2016-02-23 20:00:55 +00:00

112 lines
3.3 KiB
C

/*
* Copyright 1997 Sean Eric Fagan
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Sean Eric Fagan
* 4. Neither the name of the author may be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/* Linux/i386-specific system call handling. */
#include <sys/ptrace.h>
#include <machine/reg.h>
#include <machine/psl.h>
#include <stdio.h>
#include <sysdecode.h>
#include "truss.h"
static int
i386_linux_fetch_args(struct trussinfo *trussinfo, u_int narg)
{
struct reg regs;
struct current_syscall *cs;
lwpid_t tid;
tid = trussinfo->curthread->tid;
cs = &trussinfo->curthread->cs;
if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {
fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");
return (-1);
}
/*
* Linux passes syscall arguments in registers, not
* on the stack. Fortunately, we've got access to the
* register set. Note that we don't bother checking the
* number of arguments. And what does linux do for syscalls
* that have more than five arguments?
*/
switch (narg) {
default:
cs->args[5] = regs.r_ebp; /* Unconfirmed */
case 5:
cs->args[4] = regs.r_edi;
case 4:
cs->args[3] = regs.r_esi;
case 3:
cs->args[2] = regs.r_edx;
case 2:
cs->args[1] = regs.r_ecx;
case 1:
cs->args[0] = regs.r_ebx;
}
return (0);
}
static int
i386_linux_fetch_retval(struct trussinfo *trussinfo, long *retval, int *errorp)
{
struct reg regs;
lwpid_t tid;
tid = trussinfo->curthread->tid;
if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {
fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");
return (-1);
}
retval[0] = regs.r_eax;
retval[1] = regs.r_edx;
*errorp = !!(regs.r_eflags & PSL_C);
return (0);
}
static struct procabi i386_linux = {
"Linux ELF",
SYSDECODE_ABI_LINUX,
i386_linux_fetch_args,
i386_linux_fetch_retval
};
PROCABI(i386_linux);