| Message ID | 1648103566-15528-1-git-send-email-baihaowen@meizu.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | SUNRPC: Increase size of servername string | expand |
On Thu, 24 Mar 2022, Haowen Bai wrote: > This patch will fix the warning from smatch: > > net/sunrpc/clnt.c:562 rpc_create() error: snprintf() chops off > the last chars of 'sun->sun_path': 108 vs 48 > > Signed-off-by: Haowen Bai <baihaowen@meizu.com> > --- > net/sunrpc/clnt.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c > index c83fe61..6e0209e 100644 > --- a/net/sunrpc/clnt.c > +++ b/net/sunrpc/clnt.c > @@ -526,7 +526,7 @@ struct rpc_clnt *rpc_create(struct rpc_create_args *args) > .servername = args->servername, > .bc_xprt = args->bc_xprt, > }; > - char servername[48]; > + char servername[108]; It would be much nicer to use UNIX_PATH_MAX NeilBrown > struct rpc_clnt *clnt; > int i; > > -- > 2.7.4 > >
From: NeilBrown > Sent: 25 March 2022 02:07 > > On Thu, 24 Mar 2022, Haowen Bai wrote: > > This patch will fix the warning from smatch: > > > > net/sunrpc/clnt.c:562 rpc_create() error: snprintf() chops off > > the last chars of 'sun->sun_path': 108 vs 48 > > > > Signed-off-by: Haowen Bai <baihaowen@meizu.com> > > --- > > net/sunrpc/clnt.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c > > index c83fe61..6e0209e 100644 > > --- a/net/sunrpc/clnt.c > > +++ b/net/sunrpc/clnt.c > > @@ -526,7 +526,7 @@ struct rpc_clnt *rpc_create(struct rpc_create_args *args) > > .servername = args->servername, > > .bc_xprt = args->bc_xprt, > > }; > > - char servername[48]; > > + char servername[108]; > > It would be much nicer to use UNIX_PATH_MAX No on-stack.... Given the use: if (xprtargs.servername == NULL) { struct sockaddr_un *sun = (struct sockaddr_un *)args->address; struct sockaddr_in *sin = (struct sockaddr_in *)args->address; struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)args->address; servername[0] = '\0'; switch (args->address->sa_family) { case AF_LOCAL: snprintf(servername, sizeof(servername), "%s", sun->sun_path); break; case AF_INET: snprintf(servername, sizeof(servername), "%pI4", &sin->sin_addr.s_addr); break; case AF_INET6: snprintf(servername, sizeof(servername), "%pI6", &sin6->sin6_addr); break; default: /* caller wants default server name, but * address family isn't recognized. */ return ERR_PTR(-EINVAL); } xprtargs.servername = servername; } It looks like the AF_LOCAL case could be: xprtargs.servername = sun->sun_path; Then the buffer only needs to be big enough for the IPv6 address. For which 40 is enough. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)
From: David Laight > Sent: 25 March 2022 06:53 > > From: NeilBrown > > Sent: 25 March 2022 02:07 > > > > On Thu, 24 Mar 2022, Haowen Bai wrote: > > > This patch will fix the warning from smatch: > > > > > > net/sunrpc/clnt.c:562 rpc_create() error: snprintf() chops off > > > the last chars of 'sun->sun_path': 108 vs 48 > > > > > > Signed-off-by: Haowen Bai <baihaowen@meizu.com> > > > --- > > > net/sunrpc/clnt.c | 2 +- > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c > > > index c83fe61..6e0209e 100644 > > > --- a/net/sunrpc/clnt.c > > > +++ b/net/sunrpc/clnt.c > > > @@ -526,7 +526,7 @@ struct rpc_clnt *rpc_create(struct rpc_create_args *args) > > > .servername = args->servername, > > > .bc_xprt = args->bc_xprt, > > > }; > > > - char servername[48]; > > > + char servername[108]; > > > > It would be much nicer to use UNIX_PATH_MAX > > Not on-stack.... Ok I looked the constant up - it is 108. OTOH just looking at the code makes it look like a value that is much larger - not good on stack. Even [sizeof sun->sun_path] would probably be better. But I don't think the copy is needed at all. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)
diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c index c83fe61..6e0209e 100644 --- a/net/sunrpc/clnt.c +++ b/net/sunrpc/clnt.c @@ -526,7 +526,7 @@ struct rpc_clnt *rpc_create(struct rpc_create_args *args) .servername = args->servername, .bc_xprt = args->bc_xprt, }; - char servername[48]; + char servername[108]; struct rpc_clnt *clnt; int i;
This patch will fix the warning from smatch: net/sunrpc/clnt.c:562 rpc_create() error: snprintf() chops off the last chars of 'sun->sun_path': 108 vs 48 Signed-off-by: Haowen Bai <baihaowen@meizu.com> --- net/sunrpc/clnt.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)