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Commit f618f010 authored by Alan Stern's avatar Alan Stern Committed by Li Huafei
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USB: core: Fix duplicate endpoint bug by clearing reserved bits in the descriptor

stable inclusion
from stable-v4.19.318
commit d8418fd083d1b90a6c007cf8dcf81aeae274727b
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAGEN0
CVE: CVE-2024-41035

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=d8418fd083d1b90a6c007cf8dcf81aeae274727b



--------------------------------

commit a368ecde8a5055b627749b09c6218ef793043e47 upstream.

Syzbot has identified a bug in usbcore (see the Closes: tag below)
caused by our assumption that the reserved bits in an endpoint
descriptor's bEndpointAddress field will always be 0.  As a result of
the bug, the endpoint_is_duplicate() routine in config.c (and possibly
other routines as well) may believe that two descriptors are for
distinct endpoints, even though they have the same direction and
endpoint number.  This can lead to confusion, including the bug
identified by syzbot (two descriptors with matching endpoint numbers
and directions, where one was interrupt and the other was bulk).

To fix the bug, we will clear the reserved bits in bEndpointAddress
when we parse the descriptor.  (Note that both the USB-2.0 and USB-3.1
specs say these bits are "Reserved, reset to zero".)  This requires us
to make a copy of the descriptor earlier in usb_parse_endpoint() and
use the copy instead of the original when checking for duplicates.

Signed-off-by: default avatarAlan Stern <stern@rowland.harvard.edu>
Reported-and-tested-by: default avatar <syzbot+8693a0bb9c10b554272a@syzkaller.appspotmail.com>
Closes: https://lore.kernel.org/linux-usb/0000000000003d868e061bc0f554@google.com/
Fixes: 0a8fd134 ("USB: fix problems with duplicate endpoint addresses")
CC: Oliver Neukum <oneukum@suse.com>
CC: stable@vger.kernel.org
Link: https://lore.kernel.org/r/205a5edc-7fef-4159-b64a-80374b6b101a@rowland.harvard.edu


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Conflicts:
	drivers/usb/core/config.c
[ Resolved context conflict due to commit 63d176ed148a ("USB: core: add
endpoint-blacklist quirk") not backport. ]
Signed-off-by: default avatarLi Huafei <lihuafei1@huawei.com>
parent b263c203
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