svn commit: trunk/uClibc/libc/sysdeps/linux/common
vapier at uclibc.org
vapier at uclibc.org
Tue Dec 27 08:58:05 UTC 2005
Author: vapier
Date: 2005-12-27 00:58:04 -0800 (Tue, 27 Dec 2005)
New Revision: 12981
Log:
Aubrey writes:
When I mounted nfs on my target, the kernel crashed. And I found it
was caused by stack overflow. When I digged into it.
And I found not only "setgroups.c" but
"getgroups.c" have the matrix (__kernel_gid_t kernel_groups[n]) on the
stack which can be very large because "n" can be assigned to
NGROUPS_MAX.
And, NGROUPS_MAX is defined in the file "./linux-2.6.x/include/linux/limits.h"
#define NGROUPS_MAX 65536 /* supplemental group IDs are available */
I also changed it to do malloc.
Modified:
trunk/uClibc/libc/sysdeps/linux/common/getgroups.c
trunk/uClibc/libc/sysdeps/linux/common/setgroups.c
Changeset:
Modified: trunk/uClibc/libc/sysdeps/linux/common/getgroups.c
===================================================================
--- trunk/uClibc/libc/sysdeps/linux/common/getgroups.c 2005-12-27 08:42:13 UTC (rev 12980)
+++ trunk/uClibc/libc/sysdeps/linux/common/getgroups.c 2005-12-27 08:58:04 UTC (rev 12981)
@@ -10,6 +10,7 @@
#define sysconf __sysconf
#include "syscalls.h"
+#include <stdlib.h>
#include <unistd.h>
#define MIN(a,b) (((a)<(b))?(a):(b))
@@ -21,18 +22,25 @@
int attribute_hidden __getgroups(int n, gid_t * groups)
{
if (unlikely(n < 0)) {
+ret_error:
__set_errno(EINVAL);
return -1;
} else {
int i, ngids;
- __kernel_gid_t kernel_groups[n = MIN(n, sysconf(_SC_NGROUPS_MAX))];
+ __kernel_gid_t *kernel_groups;
+ n = MIN(n, sysconf(_SC_NGROUPS_MAX));
+ kernel_groups = (__kernel_gid_t *)malloc(sizeof(*kernel_groups) * n);
+ if (kernel_groups == NULL)
+ goto ret_error;
+
ngids = __syscall_getgroups(n, kernel_groups);
if (n != 0 && ngids > 0) {
for (i = 0; i < ngids; i++) {
groups[i] = kernel_groups[i];
}
}
+ free(kernel_groups);
return ngids;
}
}
Modified: trunk/uClibc/libc/sysdeps/linux/common/setgroups.c
===================================================================
--- trunk/uClibc/libc/sysdeps/linux/common/setgroups.c 2005-12-27 08:42:13 UTC (rev 12980)
+++ trunk/uClibc/libc/sysdeps/linux/common/setgroups.c 2005-12-27 08:58:04 UTC (rev 12981)
@@ -10,6 +10,7 @@
#define sysconf __sysconf
#include "syscalls.h"
+#include <stdlib.h>
#include <unistd.h>
#include <grp.h>
@@ -20,20 +21,27 @@
int attribute_hidden __setgroups(size_t n, const gid_t * groups)
{
if (n > (size_t) sysconf(_SC_NGROUPS_MAX)) {
+ret_error:
__set_errno(EINVAL);
return -1;
} else {
size_t i;
- __kernel_gid_t kernel_groups[n];
+ __kernel_gid_t *kernel_groups;
+ kernel_groups = (__kernel_gid_t *)malloc(sizeof(*kernel_groups) * n);
+ if (kernel_groups == NULL)
+ goto ret_error;
+
for (i = 0; i < n; i++) {
kernel_groups[i] = (groups)[i];
if (groups[i] != (gid_t) ((__kernel_gid_t) groups[i])) {
- __set_errno(EINVAL);
- return -1;
+ goto ret_error;
}
}
- return (__syscall_setgroups(n, kernel_groups));
+
+ i = __syscall_setgroups(n, kernel_groups);
+ free(kernel_groups);
+ return i;
}
}
strong_alias(__setgroups,setgroups)
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