mirror of https://gitee.com/openkylin/linux.git
d4ead16f50
This patch (as908) adds central protection in usbcore for the prototypical race between opening and unregistering a char device. The spinlock used to protect the minor-numbers array is replaced with an rwsem, which can remain locked across a call to a driver's open() method. This guarantees that open() and deregister() will be mutually exclusive. The private locks currently used in several individual drivers for this purpose are no longer necessary, and the patch removes them. The following USB drivers are affected: usblcd, idmouse, auerswald, legousbtower, sisusbvga/sisusb, ldusb, adutux, iowarrior, and usb-skeleton. As a side effect of this change, usb_deregister_dev() must not be called while holding a lock that is acquired by open(). Unfortunately a number of drivers do this, but luckily the solution is simple: call usb_deregister_dev() before acquiring the lock. In addition to these changes (and their consequent code simplifications), the patch fixes a use-after-free bug in adutux and a race between open() and release() in iowarrior. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> |
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| .. | ||
| Kconfig | ||
| Makefile | ||
| sisusb.c | ||
| sisusb.h | ||
| sisusb_con.c | ||
| sisusb_init.c | ||
| sisusb_init.h | ||
| sisusb_struct.h | ||