The cited patch added a call to dev_change_tx_queue_len in
SIOCSIFTXQLEN case.
This obsoletes the new len comparison check done before the function call.
Remove it here.
For the desicion of keep/remove the negative value check, we examine the
range check in dev_change_tx_queue_len.
On 64-bit we will fail with -ERANGE. The 32-bit int ifr_qlen will be sign
extended to 64-bits when it is passed into dev_change_tx_queue_len(). And
then for negative values this test triggers:
if (new_len != (unsigned int)new_len)
return -ERANGE;
because:
if (0xffffffffWHATEVER != 0x00000000WHATEVER)
On 32-bit the signed value will be accepted, changing behavior.
Therefore, the negative value check is kept.
Fixes: 3f76df198288 ("net: use dev_change_tx_queue_len() for SIOCSIFTXQLEN")
Signed-off-by: Tariq Toukan <tar...@mellanox.com>
Reviewed-by: Eran Ben Elisha <era...@mellanox.com>
Cc: Cong Wang <xiyou.wangc...@gmail.com>
---
net/core/dev_ioctl.c | 7 +------
1 file changed, 1 insertion(+), 6 deletions(-)
v1 -> v2:
* Retained negative value check, per comments from Cong and Dave.
* Updated commit message accordingly.
diff --git a/net/core/dev_ioctl.c b/net/core/dev_ioctl.c
index 50537ff961a7..90e8aa36881e 100644
--- a/net/core/dev_ioctl.c
+++ b/net/core/dev_ioctl.c
@@ -284,12 +284,7 @@ static int dev_ifsioc(struct net *net, struct ifreq *ifr,
unsigned int cmd)
case SIOCSIFTXQLEN:
if (ifr->ifr_qlen < 0)
return -EINVAL;
- if (dev->tx_queue_len ^ ifr->ifr_qlen) {
- err = dev_change_tx_queue_len(dev, ifr->ifr_qlen);
- if (err)
- return err;
- }
- return 0;
+ return dev_change_tx_queue_len(dev, ifr->ifr_qlen);
case SIOCSIFNAME:
ifr->ifr_newname[IFNAMSIZ-1] = '\0';
--
1.8.3.1
