From: Jon Mason Date: Mon, 15 Jul 2013 20:23:47 +0000 (-0700) Subject: NTB: Add Error Handling in ntb_device_setup X-Git-Tag: firefly_0821_release~6453^2~343 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=21720562911f038d7406654e7ea0c171cfac47b8;p=firefly-linux-kernel-4.4.55.git NTB: Add Error Handling in ntb_device_setup commit 3b12a0d15bd1559e72ad21d9d807fd2a6706f0ab upstream. If an error is encountered in ntb_device_setup, it is possible that the spci_cmd isn't populated. Writes to the offset can result in a NULL pointer dereference. This issue is easily encountered by running in NTB-RP mode, as it currently is not supported and will generate an error. To get around this issue, return if an error is encountered prior to attempting to write to the spci_cmd offset. Signed-off-by: Jon Mason Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/ntb/ntb_hw.c b/drivers/ntb/ntb_hw.c index 2dacd19e1b8a..515099ee12fe 100644 --- a/drivers/ntb/ntb_hw.c +++ b/drivers/ntb/ntb_hw.c @@ -644,10 +644,13 @@ static int ntb_device_setup(struct ntb_device *ndev) rc = -ENODEV; } + if (rc) + return rc; + /* Enable Bus Master and Memory Space on the secondary side */ writew(PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER, ndev->reg_ofs.spci_cmd); - return rc; + return 0; } static void ntb_device_free(struct ntb_device *ndev)