[arptables PATCH 2/3] Eliminate compiler warning about size passed to strncmp()

[Phil Sutter <phil@nwl.cc>]

Gcc complains about the size being equal to destination size, despite
the nul character being explicitly set in following line.

Reduce size by one to make gcc happy. While being at it, drop the
explicit nul character assignment - it is not needed as the buffer was
allocated by calloc().

Fixes: 8f586939999e0 ("fix potential buffer overflows reported by static analysis")
Signed-off-by: Phil Sutter <phil@nwl.cc>
---
 arptables.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/arptables.c b/arptables.c
index 09c9ca25217d0..2b6618c2511ef 100644
--- a/arptables.c
+++ b/arptables.c
@@ -2065,8 +2065,7 @@ int do_command(int argc, char *argv[], char **table, arptc_handle_t *handle)
 
 				target->t = fw_calloc(1, size);
 				target->t->u.target_size = size;
-				strncpy(target->t->u.user.name, jumpto, sizeof(target->t->u.user.name));
-				target->t->u.user.name[sizeof(target->t->u.user.name)-1] = '\0';
+				strncpy(target->t->u.user.name, jumpto, sizeof(target->t->u.user.name) - 1);
 				target->t->u.user.revision = target->revision;
 /*
 				target->init(target->t, &fw.nfcache);
-- 
2.24.0