[PATCH net-next v3 04/10] net: pktgen: fix 'rate 0' error handling (return -EINVAL)

[Peter Seiderer]

Given an invalid 'rate' command e.g. 'rate 0' the return value is '1',
leading to the following misleading output:

- the good case

        $ echo "rate 100" > /proc/net/pktgen/lo\@0
        $ grep "Result:" /proc/net/pktgen/lo\@0
        Result: OK: rate=100

- the bad case (before the patch)

        $ echo "rate 0" > /proc/net/pktgen/lo\@0"
        -bash: echo: write error: Invalid argument
        $ grep "Result:" /proc/net/pktgen/lo\@0
        Result: No such parameter "ate"

- with patch applied

        $ echo "rate 0" > /proc/net/pktgen/lo\@0
        -bash: echo: write error: Invalid argument
        $ grep "Result:" /proc/net/pktgen/lo\@0
        Result: Idle

Signed-off-by: Peter Seiderer <ps.rep...@gmx.net>
---
Changes v2 -> v3:
  - no changes

Changes v1 -> v2:
  - new patch
---
 net/core/pktgen.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/core/pktgen.c b/net/core/pktgen.c
index 28dbbf70e142..75c7511bf492 100644
--- a/net/core/pktgen.c
+++ b/net/core/pktgen.c
@@ -1115,7 +1115,7 @@ static ssize_t pktgen_if_write(struct file *file,
 
                i += len;
                if (!value)
-                       return len;
+                       return -EINVAL;
                pkt_dev->delay = pkt_dev->min_pkt_size*8*NSEC_PER_USEC/value;
                if (debug)
                        pr_info("Delay set at: %llu ns\n", pkt_dev->delay);
-- 
2.48.1