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Fix corner cases of xattr family syscalls decoding

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* xattr.c (print_xattr_val): Do not take insize into account, print it
as unsigned long.
Do not decode xattr values of size larger than XATTR_SIZE_MAX.
Use static buffer for fetching xattr values.
(print_xattr_list): Do not decode string when size is zero.
This commit is contained in:
Дмитрий Левин 2016-05-10 18:52:06 +00:00
parent 0efd888e22
commit ec9c31705b
1 changed files with 16 additions and 43 deletions
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59
xattr.c
View File

@ -1,7 +1,7 @@
/*
* Copyright (c) 2002-2005 Roland McGrath <roland@redhat.com>
* Copyright (c) 2004 Ulrich Drepper <drepper@redhat.com>
* Copyright (c) 2005-2015 Dmitry V. Levin <ldv@altlinux.org>
* Copyright (c) 2005-2016 Dmitry V. Levin <ldv@altlinux.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
@ -35,54 +35,30 @@
#include "xlat/xattrflags.h"
#ifndef XATTR_SIZE_MAX
# define XATTR_SIZE_MAX 65536
#endif
static void
print_xattr_val(struct tcb *tcp,
unsigned long addr,
unsigned long insize,
unsigned long size)
{
char *buf = NULL;
unsigned int len;
static char buf[XATTR_SIZE_MAX];
tprints(", ");
if (insize == 0)
goto done;
len = size;
if (size != (unsigned long) len)
goto done;
if (!len) {
tprintf("\"\", %ld", insize);
return;
}
if (!verbose(tcp) || (exiting(tcp) && syserror(tcp)))
goto done;
buf = malloc(len);
if (!buf)
goto done;
if (umoven(tcp, addr, len, buf) < 0) {
free(buf);
buf = NULL;
goto done;
}
/* Don't print terminating NUL if there is one. */
if (buf[len - 1] == '\0')
--len;
done:
if (buf) {
print_quoted_string(buf, len, 0);
free(buf);
} else {
if (!addr || size > sizeof(buf))
printaddr(addr);
else if (!size || !umoven_or_printaddr(tcp, addr, size, buf)) {
/* Don't print terminating NUL if there is one. */
if (size && buf[size - 1] == '\0')
--size;
print_quoted_string(buf, size, 0);
}
tprintf(", %ld", insize);
tprintf(", %lu", insize);
}
SYS_FUNC(setxattr)
@ -134,13 +110,10 @@ SYS_FUNC(fgetxattr)
static void
print_xattr_list(struct tcb *tcp, unsigned long addr, unsigned long size)
{
if (syserror(tcp)) {
if (!size || syserror(tcp)) {
printaddr(addr);
} else {
unsigned long len =
(size < (unsigned long) tcp->u_rval) ?
size : (unsigned long) tcp->u_rval;
printstr(tcp, addr, len);
printstr(tcp, addr, tcp->u_rval);
}
tprintf(", %lu", size);
}