Xdmx: integer overflow in GetGLXFBConfigs()

numFBConfigs & numAttribs are CARD32s and need to be bounds checked before
multiplying by structure sizes to come up with the total size to allocate,
to avoid integer overflow leading to underallocation and writing data from
the network past the end of the allocated buffer.

Reported-by: Ilja Van Sprundel <ivansprundel@ioactive.com>
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
This commit is contained in:
Alan Coopersmith 2013-04-14 09:45:26 -07:00
parent c89bcd12f4
commit 5fbd8c45b4

View File

@ -279,7 +279,10 @@ GetGLXFBConfigs(Display * dpy, int glxMajorOpcode, int *nconfigs)
return NULL;
}
attrs = (INT32 *) Xmalloc(2 * numAttribs * __GLX_SIZE_CARD32);
if (numAttribs < (INT_MAX / (2 * __GLX_SIZE_CARD32)))
attrs = Xmalloc(2 * numAttribs * __GLX_SIZE_CARD32);
else
attrs = NULL;
if (!attrs) {
UnlockDisplay(dpy);
SyncHandle();
@ -287,15 +290,16 @@ GetGLXFBConfigs(Display * dpy, int glxMajorOpcode, int *nconfigs)
}
/* Allocate memory for our config structure */
config = (__GLXFBConfig *)
Xmalloc(numFBConfigs * sizeof(__GLXFBConfig));
if (numFBConfigs < (INT_MAX / sizeof(__GLXFBConfig)))
config = Xcalloc(numFBConfigs, sizeof(__GLXFBConfig));
else
config = NULL;
if (!config) {
free(attrs);
UnlockDisplay(dpy);
SyncHandle();
return NULL;
}
memset(config, 0, numFBConfigs * sizeof(__GLXFBConfig));
fbconfigs = config;
/* Convert attribute list into our format */