[PATCH net-next v4 05/17] net: pktgen: fix 'ratep 0' error handling (return -EINVAL)

[Peter Seiderer]

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

- the good case

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

- the bad case (before the patch)

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

- with patch applied

        $ echo "ratep 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>
Reviewed-by: Simon Horman <ho...@kernel.org>
---
Changes v3 -> v4
  - add rev-by Simon Horman

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 75c7511bf492..c8a5b4d17407 100644
--- a/net/core/pktgen.c
+++ b/net/core/pktgen.c
@@ -1130,7 +1130,7 @@ static ssize_t pktgen_if_write(struct file *file,
 
                i += len;
                if (!value)
-                       return len;
+                       return -EINVAL;
                pkt_dev->delay = NSEC_PER_SEC/value;
                if (debug)
                        pr_info("Delay set at: %llu ns\n", pkt_dev->delay);
-- 
2.48.1