From 942dcb0ffa9d459af821167bd7cce94415e8278a Mon Sep 17 00:00:00 2001 From: Jisheng Zhang Date: Mon, 24 Apr 2017 12:35:51 +0000 Subject: usb: chipidea: udc: fix NULL pointer dereference if udc_start failed commit aa1f058d7d9244423b8c5a75b9484b1115df7f02 upstream. Fix below NULL pointer dereference. we set ci->roles[CI_ROLE_GADGET] too early in ci_hdrc_gadget_init(), if udc_start() fails due to some reason, the ci->roles[CI_ROLE_GADGET] check in ci_hdrc_gadget_destroy can't protect us. We fix this issue by only setting ci->roles[CI_ROLE_GADGET] if udc_start() succeed. [ 1.398550] Unable to handle kernel NULL pointer dereference at virtual address 00000000 ... [ 1.448600] PC is at dma_pool_free+0xb8/0xf0 [ 1.453012] LR is at dma_pool_free+0x28/0xf0 [ 2.113369] [] dma_pool_free+0xb8/0xf0 [ 2.118857] [] destroy_eps+0x4c/0x68 [ 2.124165] [] ci_hdrc_gadget_destroy+0x28/0x50 [ 2.130461] [] ci_hdrc_probe+0x588/0x7e8 [ 2.136129] [] platform_drv_probe+0x50/0xb8 [ 2.142066] [] driver_probe_device+0x1fc/0x2a8 [ 2.148270] [] __device_attach_driver+0x9c/0xf8 [ 2.154563] [] bus_for_each_drv+0x58/0x98 [ 2.160317] [] __device_attach+0xc4/0x138 [ 2.166072] [] device_initial_probe+0x10/0x18 [ 2.172185] [] bus_probe_device+0x94/0xa0 [ 2.177940] [] device_add+0x3f0/0x560 [ 2.183337] [] platform_device_add+0x180/0x240 [ 2.189541] [] ci_hdrc_add_device+0x440/0x4f8 [ 2.195654] [] ci_hdrc_usb2_probe+0x13c/0x2d8 [ 2.201769] [] platform_drv_probe+0x50/0xb8 [ 2.207705] [] driver_probe_device+0x1fc/0x2a8 [ 2.213910] [] __driver_attach+0xac/0xb0 [ 2.219575] [] bus_for_each_dev+0x60/0xa0 [ 2.225329] [] driver_attach+0x20/0x28 [ 2.230816] [] bus_add_driver+0x1d0/0x238 [ 2.236571] [] driver_register+0x60/0xf8 [ 2.242237] [] __platform_driver_register+0x44/0x50 [ 2.248891] [] ci_hdrc_usb2_driver_init+0x18/0x20 [ 2.255365] [] do_one_initcall+0x38/0x128 [ 2.261121] [] kernel_init_freeable+0x1ac/0x250 [ 2.267414] [] kernel_init+0x10/0x100 [ 2.272810] [] ret_from_fork+0x10/0x50 Fixes: 3f124d233e97 ("usb: chipidea: add role init and destroy APIs") Signed-off-by: Jisheng Zhang Signed-off-by: Peter Chen Signed-off-by: Greg Kroah-Hartman --- drivers/usb/chipidea/udc.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'drivers/usb/chipidea/udc.c') diff --git a/drivers/usb/chipidea/udc.c b/drivers/usb/chipidea/udc.c index d8a045fc1fdb..aff086ca97e4 100644 --- a/drivers/usb/chipidea/udc.c +++ b/drivers/usb/chipidea/udc.c @@ -1982,6 +1982,7 @@ static void udc_id_switch_for_host(struct ci_hdrc *ci) int ci_hdrc_gadget_init(struct ci_hdrc *ci) { struct ci_role_driver *rdrv; + int ret; if (!hw_read(ci, CAP_DCCPARAMS, DCCPARAMS_DC)) return -ENXIO; @@ -1994,7 +1995,10 @@ int ci_hdrc_gadget_init(struct ci_hdrc *ci) rdrv->stop = udc_id_switch_for_host; rdrv->irq = udc_irq; rdrv->name = "gadget"; - ci->roles[CI_ROLE_GADGET] = rdrv; - return udc_start(ci); + ret = udc_start(ci); + if (!ret) + ci->roles[CI_ROLE_GADGET] = rdrv; + + return ret; } -- cgit v1.2.3