motorhead/qemu
1
0
Fork 0
mirror of https://github.com/Motorhead1991/qemu.git synced 2025-08-03 07:43:54 -06:00
Code Issues Projects Releases Packages Wiki Activity Actions

cutils: Assert in-range base for string-to-integer conversions

Browse source 
POSIX states that the value of endptr is unspecified if strtol()
fails with EINVAL due to an invalid base argument.  Since none of
the callers to check_strtox_error() initialized endptr, we could
end up propagating uninitialized data back to a caller on error.
However, passing an out-of-range base is already a sign of poor
programming, so let's just assert that base is in range, at which
point check_strtox_error() can be tightened to assert that it is
receiving an initialized ep that points somewhere within the
caller's original string, regardless of whether strto*() succeeded
or failed with ERANGE.

Reported-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20181206151856.77503-1-eblake@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
This commit is contained in:
Eric Blake 2018-12-06 09:18:56 -06:00 • committed by Laurent Vivier
parent 9e722ebc06
commit 53a90b9724
1 changed files with 8 additions and 0 deletions
Download patch file Download diff file Expand all files Collapse all files

8
util/cutils.c
View file

@ -280,6 +280,7 @@ int qemu_strtosz_metric(const char *nptr, char **end, uint64_t *result)
static int check_strtox_error(const char *nptr, char *ep, static int check_strtox_error(const char *nptr, char *ep,
const char **endptr, int libc_errno) const char **endptr, int libc_errno)
{ {
assert(ep >= nptr);
if (endptr) { if (endptr) {
*endptr = ep; *endptr = ep;
} }
@ -327,6 +328,7 @@ int qemu_strtoi(const char *nptr, const char **endptr, int base,
char *ep; char *ep;
long long lresult; long long lresult;
assert((unsigned) base <= 36 && base != 1);
if (!nptr) { if (!nptr) {
if (endptr) { if (endptr) {
*endptr = nptr; *endptr = nptr;
@ -379,6 +381,7 @@ int qemu_strtoui(const char *nptr, const char **endptr, int base,
char *ep; char *ep;
long long lresult; long long lresult;
assert((unsigned) base <= 36 && base != 1);
if (!nptr) { if (!nptr) {
if (endptr) { if (endptr) {
*endptr = nptr; *endptr = nptr;
@ -435,6 +438,7 @@ int qemu_strtol(const char *nptr, const char **endptr, int base,
{ {
char *ep; char *ep;
assert((unsigned) base <= 36 && base != 1);
if (!nptr) { if (!nptr) {
if (endptr) { if (endptr) {
*endptr = nptr; *endptr = nptr;
@ -477,6 +481,7 @@ int qemu_strtoul(const char *nptr, const char **endptr, int base,
{ {
char *ep; char *ep;
assert((unsigned) base <= 36 && base != 1);
if (!nptr) { if (!nptr) {
if (endptr) { if (endptr) {
*endptr = nptr; *endptr = nptr;
@ -504,6 +509,7 @@ int qemu_strtoi64(const char *nptr, const char **endptr, int base,
{ {
char *ep; char *ep;
assert((unsigned) base <= 36 && base != 1);
if (!nptr) { if (!nptr) {
if (endptr) { if (endptr) {
*endptr = nptr; *endptr = nptr;
@ -527,6 +533,7 @@ int qemu_strtou64(const char *nptr, const char **endptr, int base,
{ {
char *ep; char *ep;
assert((unsigned) base <= 36 && base != 1);
if (!nptr) { if (!nptr) {
if (endptr) { if (endptr) {
*endptr = nptr; *endptr = nptr;
@ -594,6 +601,7 @@ int parse_uint(const char *s, unsigned long long *value, char **endptr,
char *endp = (char *)s; char *endp = (char *)s;
unsigned long long val = 0; unsigned long long val = 0;
assert((unsigned) base <= 36 && base != 1);
if (!s) { if (!s) {
r = -EINVAL; r = -EINVAL;
goto out; goto out;