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author | Takashi Iwai <tiwai@suse.de> | 2021-02-01 09:32:47 +0100 |
---|---|---|
committer | Mauro Carvalho Chehab <mchehab+huawei@kernel.org> | 2021-03-11 11:59:41 +0100 |
commit | c49206786ee252f28b7d4d155d1fff96f145a05d (patch) | |
tree | 05fd6c377af8a4ce9a5a37207a08f4e630320655 /drivers/media/usb/dvb-usb | |
parent | 13a79f14ab285120bc4977e00a7c731e8143f548 (diff) | |
download | linux-c49206786ee252f28b7d4d155d1fff96f145a05d.tar.bz2 |
media: dvb-usb: Fix use-after-free access
dvb_usb_device_init() copies the properties to the own data, so that
the callers can release the original properties later (as done in the
commit 299c7007e936 ("media: dw2102: Fix memleak on sequence of
probes")). However, it also stores dev->desc pointer that is a
reference to the original properties data. Since dev->desc is
referred later, it may result in use-after-free, in the worst case,
leading to a kernel Oops as reported.
This patch addresses the problem by allocating and copying the
properties at first, then get the desc from the copied properties.
Reported-and-tested-by: Stefan Seyfried <seife+kernel@b1-systems.com>
BugLink: http://bugzilla.opensuse.org/show_bug.cgi?id=1181104
Reviewed-by: Robert Foss <robert.foss@linaro.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Diffstat (limited to 'drivers/media/usb/dvb-usb')
-rw-r--r-- | drivers/media/usb/dvb-usb/dvb-usb-init.c | 23 |
1 files changed, 13 insertions, 10 deletions
diff --git a/drivers/media/usb/dvb-usb/dvb-usb-init.c b/drivers/media/usb/dvb-usb/dvb-usb-init.c index c78158d12540..6c9e3290af56 100644 --- a/drivers/media/usb/dvb-usb/dvb-usb-init.c +++ b/drivers/media/usb/dvb-usb/dvb-usb-init.c @@ -264,27 +264,30 @@ int dvb_usb_device_init(struct usb_interface *intf, if (du != NULL) *du = NULL; - if ((desc = dvb_usb_find_device(udev, props, &cold)) == NULL) { + d = kzalloc(sizeof(*d), GFP_KERNEL); + if (!d) { + err("no memory for 'struct dvb_usb_device'"); + return -ENOMEM; + } + + memcpy(&d->props, props, sizeof(struct dvb_usb_device_properties)); + + desc = dvb_usb_find_device(udev, &d->props, &cold); + if (!desc) { deb_err("something went very wrong, device was not found in current device list - let's see what comes next.\n"); - return -ENODEV; + ret = -ENODEV; + goto error; } if (cold) { info("found a '%s' in cold state, will try to load a firmware", desc->name); ret = dvb_usb_download_firmware(udev, props); if (!props->no_reconnect || ret != 0) - return ret; + goto error; } info("found a '%s' in warm state.", desc->name); - d = kzalloc(sizeof(struct dvb_usb_device), GFP_KERNEL); - if (d == NULL) { - err("no memory for 'struct dvb_usb_device'"); - return -ENOMEM; - } - d->udev = udev; - memcpy(&d->props, props, sizeof(struct dvb_usb_device_properties)); d->desc = desc; d->owner = owner; |