From: Frank de Brabander debrabander@gmail.com
[ Upstream commit cecaa76b2919aac2aa584ce476e9fcd5b084add5 ]
If mmap() fails it returns MAP_FAILED, which is defined as ((void *) -1). The current if-statement incorrectly tests if *ring is NULL.
Fixes: 358be656406d ("selftests/net: add txring_overwrite") Signed-off-by: Frank de Brabander debrabander@gmail.com Acked-by: Willem de Bruijn willemb@google.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- tools/testing/selftests/net/txring_overwrite.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/tools/testing/selftests/net/txring_overwrite.c +++ b/tools/testing/selftests/net/txring_overwrite.c @@ -113,7 +113,7 @@ static int setup_tx(char **ring)
*ring = mmap(0, req.tp_block_size * req.tp_block_nr, PROT_READ | PROT_WRITE, MAP_SHARED, fdt, 0); - if (!*ring) + if (*ring == MAP_FAILED) error(1, errno, "mmap");
return fdt;