> -----Original Message----- > From: devel [mailto:driverdev-devel-bounces@xxxxxxxxxxxxxxxxxxxxxx] On > Behalf Of K. Y. Srinivasan > Sent: Tuesday, April 28, 2015 9:15 > To: davem@xxxxxxxxxxxxx; netdev@xxxxxxxxxxxxxxx; linux- > kernel@xxxxxxxxxxxxxxx; devel@xxxxxxxxxxxxxxxxxxxxxx; olaf@xxxxxxxxx; > apw@xxxxxxxxxxxxx; jasowang@xxxxxxxxxx > Subject: [PATCH net 1/1] hv_netvsc: Fix a bug in netvsc_start_xmit() > > Commit commit b08cc79155fc26d0d112b1470d1ece5034651a4b > eliminated memory > allocation in the packet send path. This commit introduced a bug since it > did not account for the case if the skb was cloned. Fix this bug by > using the pre-reserved head room only if the skb is not cloned. > > Signed-off-by: K. Y. Srinivasan <kys@xxxxxxxxxxxxx> > --- > drivers/net/hyperv/netvsc_drv.c | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/drivers/net/hyperv/netvsc_drv.c > b/drivers/net/hyperv/netvsc_drv.c > index a3a9d38..7eb0251 100644 > --- a/drivers/net/hyperv/netvsc_drv.c > +++ b/drivers/net/hyperv/netvsc_drv.c > @@ -421,7 +421,7 @@ check_size: > > pkt_sz = sizeof(struct hv_netvsc_packet) + RNDIS_AND_PPI_SIZE; > > - if (head_room < pkt_sz) { > + if (skb->cloned || head_room < pkt_sz) { > packet = kmalloc(pkt_sz, GFP_ATOMIC); > if (!packet) { > /* out of memory, drop packet */ > -- Without the patch, the guest can panic due to memory corruption. I confirm the patch can fix the panic I saw. Tested-by: Dexuan Cui <decui@xxxxxxxxxxxxx> Thanks, -- Dexuan _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
