On Mon, Feb 06, 2023 at 06:27:54PM +0100, Alexandra Winter wrote: > From: Thorsten Winkler <twinkler@xxxxxxxxxxxxx> > > This LWN article explains the rationale for this change > https: //lwn.net/Articles/69419/ https://lwn.net/Articles/69419/ > Ie. snprintf() returns what *would* be the resulting length, > while scnprintf() returns the actual length. Ok, but in most cases in this patch the return value is not checked. Is there any value in this change in those cases? > Reported-by: Jules Irenge <jbi.octave@xxxxxxxxx> > Reviewed-by: Alexandra Winkler <wintera@xxxxxxxxxxxxx> s/Winkler/Winter/ ? > Signed-off-by: Thorsten Winkler <twinkler@xxxxxxxxxxxxx> > Signed-off-by: Alexandra Winter <wintera@xxxxxxxxxxxxx> ... > diff --git a/drivers/s390/net/qeth_l3_main.c b/drivers/s390/net/qeth_l3_main.c > index 1cf4e354693f..af4e60d2917e 100644 > --- a/drivers/s390/net/qeth_l3_main.c > +++ b/drivers/s390/net/qeth_l3_main.c > @@ -47,9 +47,9 @@ int qeth_l3_ipaddr_to_string(enum qeth_prot_versions proto, const u8 *addr, > char *buf) > { > if (proto == QETH_PROT_IPV4) > - return sprintf(buf, "%pI4", addr); > + return scnprintf(buf, INET_ADDRSTRLEN, "%pI4", addr); > else > - return sprintf(buf, "%pI6", addr); > + return scnprintf(buf, INET6_ADDRSTRLEN, "%pI6", addr); > } This seems to be the once case where the return value is not ignored. Of the 4 callers of qeth_l3_ipaddr_to_string, two don't ignore the return value. And I agree in those cases this change seems correct. However, amongst other usages of the return value, those callers also check for a return < 0 from this function. Can that occur, in the sprintf or scnprintf case?
