The patch titled
     SCSI sd: udev accessing an uninitialized scsi_disk results in a crash
has been added to the -mm tree.  Its filename is
     scsi-sd-udev-accessing-an-uninitialized-scsi_disk-results-in-a-crash.patch

*** Remember to use Documentation/SubmitChecklist when testing your code ***

See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this

------------------------------------------------------
Subject: SCSI sd: udev accessing an uninitialized scsi_disk results in a crash
From: Nagendra Singh Tomar <[EMAIL PROTECTED]>

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 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 <[EMAIL PROTECTED]>
Cc: Greg KH <[EMAIL PROTECTED]>
Cc: James Bottomley <[EMAIL PROTECTED]>
Cc: <[EMAIL PROTECTED]>
Signed-off-by: Andrew Morton <[EMAIL PROTECTED]>
---

 drivers/scsi/sd.c |   20 ++++++++++----------
 1 files changed, 10 insertions(+), 10 deletions(-)

diff -puN 
drivers/scsi/sd.c~scsi-sd-udev-accessing-an-uninitialized-scsi_disk-results-in-a-crash
 drivers/scsi/sd.c
--- 
a/drivers/scsi/sd.c~scsi-sd-udev-accessing-an-uninitialized-scsi_disk-results-in-a-crash
+++ a/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;
_

Patches currently in -mm which might be from [EMAIL PROTECTED] are

scsi-sd-udev-accessing-an-uninitialized-scsi_disk-results-in-a-crash.patch

-
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to