答复: [PATCH v3] pktgen: Fix invalid clone_skb override
From: zhudi (J) <hidden>
Date: 2021-08-03 02:17:26
Also in:
lkml
From: Nick Richardson <redacted>
When the netif_receive xmit_mode is set, a line is supposed to set
clone_skb to a default 0 value. This line is made redundant due to a
preceding line that checks if clone_skb is more than zero and returns
-ENOTSUPP.
Only the positive case for clone_skb needs to be checked. It
is impossible for a user to set clone_skb to a negative number.
When a user passes a negative value for clone_skb, the num_arg()
function stops parsing at the first nonnumeric value.
For example: "clone_skb -200" would stop parsing at the
first char ('-') and return zero for the new clone_skb value.
The value read by num_arg() cannot be overflow-ed into the negative
range, since it is an unsigned long.module_param(pg_clone_skb_d, int, 0); This kernel parameter can also set the value of pkt_dev->clone_skb In pktgen_add_device() and the value can be negative.
quoted hunk ↗ jump to hunk
Remove redundant line that sets clone_skb to zero. If clone_skb is equal to zero then set xmit_mode to netif_receive as usual and return no error. Signed-off-by: Nick Richardson <redacted> --- net/core/pktgen.c | 5 ----- 1 file changed, 5 deletions(-)diff --git a/net/core/pktgen.c b/net/core/pktgen.c index 7e258d255e90..314f97acf39d 100644 --- a/net/core/pktgen.c +++ b/net/core/pktgen.c@@ -1190,11 +1190,6 @@ static ssize_t pktgen_if_write(struct file *file, * pktgen_xmit() is called */ pkt_dev->last_ok = 1; - - /* override clone_skb if user passed default value - * at module loading time - */ - pkt_dev->clone_skb = 0; } else if (strcmp(f, "queue_xmit") == 0) { pkt_dev->xmit_mode = M_QUEUE_XMIT; pkt_dev->last_ok = 1; --2.32.0.554.ge1b32706d8-goog