| Message ID | 20170306223054.25666-1-eblake@redhat.com |
|---|---|
| State | New |
| Headers | show |
Hi Vladimir, On 03/06/2017 07:30 PM, Eric Blake wrote: > From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> > > Comparison symbol is misused. It may lead to memory corruption. > Introduced in commit 7d3123e. > > Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> > Message-Id: <20170203154757.36140-6-vsementsov@virtuozzo.com> > [eblake: add CVE details] > Signed-off-by: Eric Blake <eblake@redhat.com> > Reviewed-by: Marc-André Lureau <address@hidden> > --- > > This one still hasn't been merged in; sending separately since the > rest of my NBD series is now 2.10 material: > https://lists.gnu.org/archive/html/qemu-devel/2017-02/msg04528.html > > nbd/client.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/nbd/client.c b/nbd/client.c > index 5c9dee3..165b33e 100644 > --- a/nbd/client.c > +++ b/nbd/client.c > @@ -94,7 +94,7 @@ static ssize_t drop_sync(QIOChannel *ioc, size_t size) > char small[1024]; > char *buffer; > > - buffer = sizeof(small) < size ? small : g_malloc(MIN(65536, size)); > + buffer = sizeof(small) > size ? small : g_malloc(MIN(65536, size)); here ">=" seems correct/safe. (if size is 1024, use small stack buffer too). > while (size > 0) { > ssize_t count = read_sync(ioc, buffer, MIN(65536, size)); >
07.03.2017 03:10, Philippe Mathieu-Daudé wrote: > Hi Vladimir, > > On 03/06/2017 07:30 PM, Eric Blake wrote: >> From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> >> >> Comparison symbol is misused. It may lead to memory corruption. >> Introduced in commit 7d3123e. >> >> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> >> Message-Id: <20170203154757.36140-6-vsementsov@virtuozzo.com> >> [eblake: add CVE details] >> Signed-off-by: Eric Blake <eblake@redhat.com> >> Reviewed-by: Marc-André Lureau <address@hidden> >> --- >> >> This one still hasn't been merged in; sending separately since the >> rest of my NBD series is now 2.10 material: >> https://lists.gnu.org/archive/html/qemu-devel/2017-02/msg04528.html >> >> nbd/client.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/nbd/client.c b/nbd/client.c >> index 5c9dee3..165b33e 100644 >> --- a/nbd/client.c >> +++ b/nbd/client.c >> @@ -94,7 +94,7 @@ static ssize_t drop_sync(QIOChannel *ioc, size_t size) >> char small[1024]; >> char *buffer; >> >> - buffer = sizeof(small) < size ? small : g_malloc(MIN(65536, size)); >> + buffer = sizeof(small) > size ? small : g_malloc(MIN(65536, size)); > > here ">=" seems correct/safe. > (if size is 1024, use small stack buffer too). Agree. > >> while (size > 0) { >> ssize_t count = read_sync(ioc, buffer, MIN(65536, size)); >>
On 03/06/2017 04:30 PM, Eric Blake wrote: > From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> > > Comparison symbol is misused. It may lead to memory corruption. > Introduced in commit 7d3123e. > > Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> > Message-Id: <20170203154757.36140-6-vsementsov@virtuozzo.com> > [eblake: add CVE details] > Signed-off-by: Eric Blake <eblake@redhat.com> > Reviewed-by: Marc-André Lureau <address@hidden> Blergh. This R-b isn't correct. Sending v2 with fixed attributions, and with >= instead of >.
diff --git a/nbd/client.c b/nbd/client.c index 5c9dee3..165b33e 100644 --- a/nbd/client.c +++ b/nbd/client.c @@ -94,7 +94,7 @@ static ssize_t drop_sync(QIOChannel *ioc, size_t size) char small[1024]; char *buffer; - buffer = sizeof(small) < size ? small : g_malloc(MIN(65536, size)); + buffer = sizeof(small) > size ? small : g_malloc(MIN(65536, size)); while (size > 0) { ssize_t count = read_sync(ioc, buffer, MIN(65536, size));