Fix corner cases of xattr family syscalls decoding
* 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.
diff --git a/xattr.c b/xattr.c
index c47ebd6..30a8467 100644
--- a/xattr.c
+++ b/xattr.c
@@ -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 @@
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);
}
