From: Alexey Kuznetsov Date: Tue, 17 Nov 2009 22:10:11 +0000 (-0800) Subject: [SCSI] fix crash when disconnecting usb storage X-Git-Tag: upstream/snapshot3+hdmi~16510^2 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=4e46bf89972b9d98a9f282a9fed2359756a5e34e;p=platform%2Fadaptation%2Frenesas_rcar%2Frenesas_kernel.git [SCSI] fix crash when disconnecting usb storage __scsi_remove_device() in scsi_forget_host() is executed out of scan_mutex and races with scsi_destroy_sdev() <- scsi_sysfs_add_devices() <- scsi_finish_async_scan(). The result is use after free and/or double free, oops. The fix is simple, move scsi_forget_host() under scan_mutex. scsi_forget_host() is just sequence of __scsi_remove_device(). All another calls of __scsi_remove_device() are made under scan_mutex. So that it is safe. Signed-off-by: Alexey Kuznetsov Signed-off-by: Denis V. Lunev Signed-off-by: Andrew Morton Signed-off-by: James Bottomley --- diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c index 5fd2da4..c968cc3 100644 --- a/drivers/scsi/hosts.c +++ b/drivers/scsi/hosts.c @@ -164,8 +164,8 @@ void scsi_remove_host(struct Scsi_Host *shost) return; } spin_unlock_irqrestore(shost->host_lock, flags); - mutex_unlock(&shost->scan_mutex); scsi_forget_host(shost); + mutex_unlock(&shost->scan_mutex); scsi_proc_host_rm(shost); spin_lock_irqsave(shost->host_lock, flags);