[Bug 3037] New: scanf handles %p as an integer, truncated value on 64bits platforms
bugzilla at busybox.net
bugzilla at busybox.net
Fri Dec 31 10:38:45 UTC 2010
https://bugs.busybox.net/show_bug.cgi?id=3037
Summary: scanf handles %p as an integer, truncated value on
64bits platforms
Product: uClibc
Version: 0.9.32
Platform: PC
OS/Version: Linux
Status: NEW
Severity: normal
Priority: P5
Component: stdio
AssignedTo: unassigned at uclibc.org
ReportedBy: eric.hassold at gmail.com
CC: uclibc-cvs at uclibc.org
Estimated Hours: 0.0
Created attachment 2827
--> https://bugs.busybox.net/attachment.cgi?id=2827
patch for scanf to handle %p as long on 64bits platforms
When scanning %p conversion, sscanf stores value as an unsigned integer. On
64bits platforms (e.g. x86_64), this causes returned pointers to be invalid
since high-word is lost. Test to reproduce:
#include <stdio.h>
#define PREFIX "ZZZZZ"
int main (int qrgc, char **argv) {
void *p = (void*) 0x1122334455667788;
char *s = PREFIX "0xABCD00004321";
sscanf(s,PREFIX"%p",&p);
printf("scanned '%s', got %p\n",s,p);
return 0;
}
This was observed with latest snapshot from master branch, but since code in
_sscanf.c hasn't been modified since 2009, bug should exist in several prior
releases (while affecting only 64bits platforms).
To work around this, I modified QUAL_CHARS so %p conversion uses PDS value
(like %t modifier) when calling store_inttype(). Patch attached.
--
Configure bugmail: https://bugs.busybox.net/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are on the CC list for the bug.
More information about the uClibc-cvs
mailing list