strace/personality.c
Dmitry V. Levin 0297e0c067 Handle unlikely errors from personality syscall
Despite being marked as SYSCALL_NEVER_FAILS, personality syscall still
might report a failure on some architectures due to obscure kernel
bugs.  Check for this unlikely case and let users know that their
kernel has gone bananas.

* personality.c (SYS_FUNC(personality)): Do not parse syscall return
value in case of syserror.
2015-12-27 00:18:35 +00:00

70 lines
2.3 KiB
C

/*
* Copyright (c) 2015 Dmitry V. Levin <ldv@altlinux.org>
* All rights reserved.
*
* 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. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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 "defs.h"
#include <linux/personality.h>
#include "xlat/personality_types.h"
#include "xlat/personality_flags.h"
SYS_FUNC(personality)
{
unsigned int pers;
if (entering(tcp)) {
pers = tcp->u_arg[0];
if (0xffffffff == pers) {
tprints("0xffffffff");
} else {
printxval(personality_types, pers & PER_MASK, "PER_???");
pers &= ~PER_MASK;
if (pers) {
tprints("|");
printflags(personality_flags, pers, NULL);
}
}
return 0;
}
if (syserror(tcp))
return 0;
pers = tcp->u_rval;
const char *type = xlookup(personality_types, pers & PER_MASK);
char *p;
static char outstr[1024];
if (type)
p = stpcpy(outstr, type);
else
p = outstr + sprintf(outstr, "%#x /* %s */", pers & PER_MASK, "PER_???");
pers &= ~PER_MASK;
if (pers)
strcpy(p, sprintflags("|", personality_flags, pers));
tcp->auxstr = outstr;
return RVAL_HEX | RVAL_STR;
}