Commits
Wei Liu committed e9d8b2c2968
xen-netback: disable rogue vif in kthread context When netback discovers frontend is sending malformed packet it will disables the interface which serves that frontend. However disabling a network interface involving taking a mutex which cannot be done in softirq context, so we need to defer this process to kthread context. This patch does the following: 1. introduce a flag to indicate the interface is disabled. 2. check that flag in TX path, don't do any work if it's true. 3. check that flag in RX path, turn off that interface if it's true. The reason to disable it in RX path is because RX uses kthread. After this change the behavior of netback is still consistent -- it won't do any TX work for a rogue frontend, and the interface will be eventually turned off. Also change a "continue" to "break" after xenvif_fatal_tx_err, as it doesn't make sense to continue processing packets if frontend is rogue. This is a fix for XSA-90. Reported-by: Török Edwin <edwin@etorok.net> Signed-off-by: Wei Liu <wei.liu2@citrix.com> Cc: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Acked-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>