4.4-stable review patch. If anyone has any objections, please let me know.
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From: Rodrigo Rivas Costa rodrigorivascosta@gmail.com
commit a955358d54695e4ad9f7d6489a7ac4d69a8fc711 upstream.
Doing `ioctl(HIDIOCGFEATURE)` in a tight loop on a hidraw device and then disconnecting the device, or unloading the driver, can cause a NULL pointer dereference.
When a hidraw device is destroyed it sets 0 to `dev->exist`. Most functions check 'dev->exist' before doing its work, but `hidraw_get_report()` was missing that check.
Cc: stable@vger.kernel.org Signed-off-by: Rodrigo Rivas Costa rodrigorivascosta@gmail.com Signed-off-by: Jiri Kosina jkosina@suse.cz Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/hid/hidraw.c | 5 +++++ 1 file changed, 5 insertions(+)
--- a/drivers/hid/hidraw.c +++ b/drivers/hid/hidraw.c @@ -197,6 +197,11 @@ static ssize_t hidraw_get_report(struct int ret = 0, len; unsigned char report_number;
+ if (!hidraw_table[minor] || !hidraw_table[minor]->exist) { + ret = -ENODEV; + goto out; + } + dev = hidraw_table[minor]->hid;
if (!dev->ll_driver->raw_request) {