[PATCH 5.15 267/317] net: sunrpc: Fix an off by one in rpc_sockaddr2uaddr()

From: Sasha Levin
Date: Mon Mar 25 2024 - 06:05:07 EST


From: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>

[ Upstream commit d6f4de70f73a106986ee315d7d512539f2f3303a ]

The intent is to check if the strings' are truncated or not. So, >= should
be used instead of >, because strlcat() and snprintf() return the length of
the output, excluding the trailing NULL.

Fixes: a02d69261134 ("SUNRPC: Provide functions for managing universal addresses")
Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
Reviewed-by: Benjamin Coddington <bcodding@xxxxxxxxxx>
Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
net/sunrpc/addr.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/sunrpc/addr.c b/net/sunrpc/addr.c
index d435bffc61999..97ff11973c493 100644
--- a/net/sunrpc/addr.c
+++ b/net/sunrpc/addr.c
@@ -284,10 +284,10 @@ char *rpc_sockaddr2uaddr(const struct sockaddr *sap, gfp_t gfp_flags)
}

if (snprintf(portbuf, sizeof(portbuf),
- ".%u.%u", port >> 8, port & 0xff) > (int)sizeof(portbuf))
+ ".%u.%u", port >> 8, port & 0xff) >= (int)sizeof(portbuf))
return NULL;

- if (strlcat(addrbuf, portbuf, sizeof(addrbuf)) > sizeof(addrbuf))
+ if (strlcat(addrbuf, portbuf, sizeof(addrbuf)) >= sizeof(addrbuf))
return NULL;

return kstrdup(addrbuf, gfp_flags);
--
2.43.0