From 60829145f1e2650b31ebe6a0ec70a9725b38fa2c Mon Sep 17 00:00:00 2001 From: M Chetan Kumar Date: Tue, 16 May 2023 21:09:46 +0530 Subject: net: wwan: iosm: fix NULL pointer dereference when removing device In suspend and resume cycle, the removal and rescan of device ends up in NULL pointer dereference. During driver initialization, if the ipc_imem_wwan_channel_init() fails to get the valid device capabilities it returns an error and further no resource (wwan struct) will be allocated. Now in this situation if driver removal procedure is initiated it would result in NULL pointer exception since unallocated wwan struct is dereferenced inside ipc_wwan_deinit(). ipc_imem_run_state_worker() to handle the called functions return value and to release the resource in failure case. It also reports the link down event in failure cases. The user space application can handle this event to do a device reset for restoring the device communication. Fixes: 3670970dd8c6 ("net: iosm: shared memory IPC interface") Reported-by: Samuel Wein PhD Closes: https://lore.kernel.org/netdev/20230427140819.1310f4bd@kernel.org/T/ Signed-off-by: M Chetan Kumar Reviewed-by: Simon Horman Signed-off-by: David S. Miller --- drivers/net/wwan/iosm/iosm_ipc_imem_ops.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) (limited to 'drivers/net/wwan/iosm/iosm_ipc_imem_ops.c') diff --git a/drivers/net/wwan/iosm/iosm_ipc_imem_ops.c b/drivers/net/wwan/iosm/iosm_ipc_imem_ops.c index 66b90cc4c3460..109cf89304888 100644 --- a/drivers/net/wwan/iosm/iosm_ipc_imem_ops.c +++ b/drivers/net/wwan/iosm/iosm_ipc_imem_ops.c @@ -77,8 +77,8 @@ out: } /* Initialize wwan channel */ -void ipc_imem_wwan_channel_init(struct iosm_imem *ipc_imem, - enum ipc_mux_protocol mux_type) +int ipc_imem_wwan_channel_init(struct iosm_imem *ipc_imem, + enum ipc_mux_protocol mux_type) { struct ipc_chnl_cfg chnl_cfg = { 0 }; @@ -87,7 +87,7 @@ void ipc_imem_wwan_channel_init(struct iosm_imem *ipc_imem, /* If modem version is invalid (0xffffffff), do not initialize WWAN. */ if (ipc_imem->cp_version == -1) { dev_err(ipc_imem->dev, "invalid CP version"); - return; + return -EIO; } ipc_chnl_cfg_get(&chnl_cfg, ipc_imem->nr_of_channels); @@ -104,9 +104,13 @@ void ipc_imem_wwan_channel_init(struct iosm_imem *ipc_imem, /* WWAN registration. */ ipc_imem->wwan = ipc_wwan_init(ipc_imem, ipc_imem->dev); - if (!ipc_imem->wwan) + if (!ipc_imem->wwan) { dev_err(ipc_imem->dev, "failed to register the ipc_wwan interfaces"); + return -ENOMEM; + } + + return 0; } /* Map SKB to DMA for transfer */ -- cgit v1.2.3