Messages in this thread Patch in this message | | | From | "Kambo Lohan" <> | Subject | [PATCH] [UPDATED] pktgen fixes .... | Date | Thu, 10 Jul 2003 13:40:04 -0400 |
| |
That last fix was bad... the skb->users refcount change made it possible for the skb to get double freed as skb->users was only incremented from one immediately after calling dev_hard_xmit, this should address that I hope. I now see thats what the old code was trying to avoid, but the old way fails if the first packet attempted failed dev_hard_xmit. So it needs a fix somehow. I am testing this by looping a script that starts pktgen with count=10000 and clone_skb=100. Making sure it does not soft hang (requiring a control c) or cause mem leaks.
Here is the updated patch. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
--- linux-2.4.21/net/core/pktgen.c 2002-11-28 18:53:15.000000000 -0500 +++ linux-2.4-kjp/net/core/pktgen.c 2003-07-10 13:22:17.000000000 -0400 @@ -34,6 +34,7 @@ * * The new changes seem to have a performance impact of around 1%, * as far as I can tell. * --Ben Greear <greearb@candelatech.com> + * Fix refcount off by one if first packet fails, potential null deref, memleak 030710- KJP * * Renamed multiskb to clone_skb and cleaned up sending core for two distinct * skb modes. A clone_skb=0 mode for Ben "ranges" work and a clone_skb != 0 @@ -84,9 +85,9 @@ #define cycles() ((u32)get_cycles())
-#define VERSION "pktgen version 1.2" +#define VERSION "pktgen version 1.2.1" static char version[] __initdata = - "pktgen.c: v1.2: Packet Generator for packet performance testing.\n"; + "pktgen.c: v1.2.1: Packet Generator for packet performance testing.\n";
/* Used to help with determining the pkts on receive */
@@ -613,12 +614,11 @@ kfree_skb(skb); skb = fill_packet(odev, info); if (skb == NULL) { - break; + goto out_reldev; } fp++; fp_tmp = 0; /* reset counter */ } - atomic_inc(&skb->users); }
nr_frags = skb_shinfo(skb)->nr_frags; @@ -626,7 +626,9 @@ spin_lock_bh(&odev->xmit_lock); if (!netif_queue_stopped(odev)) {
+ atomic_inc(&skb->users); if (odev->hard_start_xmit(skb, odev)) { + atomic_dec(&skb->users); if (net_ratelimit()) { printk(KERN_INFO "Hard xmit error\n"); } @@ -634,9 +636,9 @@ last_ok = 0; } else { - last_ok = 1; - info->sofar++; - info->seq_num++; + last_ok = 1; + info->sofar++; + info->seq_num++; } } else { @@ -731,6 +733,8 @@ (unsigned long long) info->errors ); } + + kfree_skb(skb);
out_reldev: if (odev) {
_________________________________________________________________ MSN 8 with e-mail virus protection service: 2 months FREE* http://join.msn.com/?page=features/virus
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |