diff options
| author | Subash Abhinov Kasiviswanathan <subashab@codeaurora.org> | 2020-11-13 13:12:05 -0700 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2020-11-16 16:34:49 -0800 |
| commit | fc70f5bf5e525dde81565f0a30d5e39168062eba (patch) | |
| tree | e8e75cd3c40aac3b4aaaa1783656942338890ed0 /drivers/net/ethernet | |
| parent | 9c79a8ab5f124db01eb1d7287454a702f0d4252f (diff) | |
net: qualcomm: rmnet: Fix incorrect receive packet handling during cleanup
During rmnet unregistration, the real device rx_handler is first cleared
followed by the removal of rx_handler_data after the rcu synchronization.
Any packets in the receive path may observe that the rx_handler is NULL.
However, there is no check when dereferencing this value to use the
rmnet_port information.
This fixes following splat by adding the NULL check.
Unable to handle kernel NULL pointer dereference at virtual
address 000000000000000d
pc : rmnet_rx_handler+0x124/0x284
lr : rmnet_rx_handler+0x124/0x284
rmnet_rx_handler+0x124/0x284
__netif_receive_skb_core+0x758/0xd74
__netif_receive_skb+0x50/0x17c
process_backlog+0x15c/0x1b8
napi_poll+0x88/0x284
net_rx_action+0xbc/0x23c
__do_softirq+0x20c/0x48c
Fixes: ceed73a2cf4a ("drivers: net: ethernet: qualcomm: rmnet: Initial implementation")
Signed-off-by: Sean Tranchetti <stranche@codeaurora.org>
Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
Link: https://lore.kernel.org/r/1605298325-3705-1-git-send-email-subashab@codeaurora.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'drivers/net/ethernet')
| -rw-r--r-- | drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c b/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c index 29a7bfa2584d..3d7d3ab383f8 100644 --- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c +++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c @@ -188,6 +188,11 @@ rx_handler_result_t rmnet_rx_handler(struct sk_buff **pskb) dev = skb->dev; port = rmnet_get_port_rcu(dev); + if (unlikely(!port)) { + atomic_long_inc(&skb->dev->rx_nohandler); + kfree_skb(skb); + goto done; + } switch (port->rmnet_mode) { case RMNET_EPMODE_VND: |