From 017f2e37ae19ccd28e5edd965741fc374194c5dd Mon Sep 17 00:00:00 2001 From: Nagendra Singh Tomar Date: Fri, 2 Feb 2007 17:34:56 +0530 Subject: [PATCH] [SCSI] sd: udev accessing an uninitialized scsi_disk field results in a crash sd_probe() calls class_device_add() even before initializing the sdkp->device variable. class_device_add() eventually results in the user mode udev program to be called. udev program can read the the allow_restart attribute of the newly created scsi device. This is resulting in a crash as the show function for allow_restart (i.e sd_show_allow_restart) returns the attribute value by reading the sdkp->device->allow_restart variable. As the sdkp->device is not initialized before calling the user mode hotplug helper, this results in a crash. The patch below solves it by calling class_device_add() only after the necessary fields in the scsi_disk structure are initialized properly. Signed-off-by: Nagendra Singh Tomar Signed-off-by: James Bottomley --- drivers/scsi/sd.c | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index 978bfc1e0c6a..b781a90d6699 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -1647,16 +1647,6 @@ static int sd_probe(struct device *dev) if (error) goto out_put; - class_device_initialize(&sdkp->cdev); - sdkp->cdev.dev = &sdp->sdev_gendev; - sdkp->cdev.class = &sd_disk_class; - strncpy(sdkp->cdev.class_id, sdp->sdev_gendev.bus_id, BUS_ID_SIZE); - - if (class_device_add(&sdkp->cdev)) - goto out_put; - - get_device(&sdp->sdev_gendev); - sdkp->device = sdp; sdkp->driver = &sd_template; sdkp->disk = gd; @@ -1670,6 +1660,16 @@ static int sd_probe(struct device *dev) sdp->timeout = SD_MOD_TIMEOUT; } + class_device_initialize(&sdkp->cdev); + sdkp->cdev.dev = &sdp->sdev_gendev; + sdkp->cdev.class = &sd_disk_class; + strncpy(sdkp->cdev.class_id, sdp->sdev_gendev.bus_id, BUS_ID_SIZE); + + if (class_device_add(&sdkp->cdev)) + goto out_put; + + get_device(&sdp->sdev_gendev); + gd->major = sd_major((index & 0xf0) >> 4); gd->first_minor = ((index & 0xf) << 4) | (index & 0xfff00); gd->minors = 16; -- 2.30.2