diff options
| author | David Vrabel <david.vrabel@citrix.com> | 2013-02-14 03:18:57 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-02-28 06:32:27 -0800 |
| commit | 436d1b8ff7eb7ac9e2569ad780c33bd4287d0526 (patch) | |
| tree | 7282140605fb4c9d965b33637e275cd224fc2e85 | |
| parent | aa1bada15c8ce41ea5b3b9392a85e6e2e07849ff (diff) | |
xen-netback: correctly return errors from netbk_count_requests()
[ Upstream commit 35876b5ffc154c357476b2c3bdab10feaf4bd8f0 ]
netbk_count_requests() could detect an error, call
netbk_fatal_tx_error() but return 0. The vif may then be used
afterwards (e.g., in a call to netbk_tx_error().
Since netbk_fatal_tx_error() could set vif->refcnt to 1, the vif may
be freed immediately after the call to netbk_fatal_tx_error() (e.g.,
if the vif is also removed).
Netback thread Xenwatch thread
-------------------------------------------
netbk_fatal_tx_err() netback_remove()
xenvif_disconnect()
...
free_netdev()
netbk_tx_err() Oops!
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Jan Beulich <JBeulich@suse.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reported-by: Christopher S. Aker <caker@theshore.net>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/net/xen-netback/netback.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c index 6ed44c3401dc..1260bf0d7e0e 100644 --- a/drivers/net/xen-netback/netback.c +++ b/drivers/net/xen-netback/netback.c @@ -870,13 +870,13 @@ static int netbk_count_requests(struct xenvif *vif, if (frags >= work_to_do) { netdev_err(vif->dev, "Need more frags\n"); netbk_fatal_tx_err(vif); - return -frags; + return -ENODATA; } if (unlikely(frags >= MAX_SKB_FRAGS)) { netdev_err(vif->dev, "Too many frags\n"); netbk_fatal_tx_err(vif); - return -frags; + return -E2BIG; } memcpy(txp, RING_GET_REQUEST(&vif->tx, cons + frags), @@ -884,7 +884,7 @@ static int netbk_count_requests(struct xenvif *vif, if (txp->size > first->size) { netdev_err(vif->dev, "Frag is bigger than frame.\n"); netbk_fatal_tx_err(vif); - return -frags; + return -EIO; } first->size -= txp->size; @@ -894,7 +894,7 @@ static int netbk_count_requests(struct xenvif *vif, netdev_err(vif->dev, "txp->offset: %x, size: %u\n", txp->offset, txp->size); netbk_fatal_tx_err(vif); - return -frags; + return -EINVAL; } } while ((txp++)->flags & XEN_NETTXF_more_data); return frags; |