linux/drivers/usb/mon
Tadeusz Struk a659daf63d usb: mon: make mmapped memory read only
Syzbot found an issue in usbmon module, where the user space client can
corrupt the monitor's internal memory, causing the usbmon module to
crash the kernel with segfault, UAF, etc.

The reproducer mmaps the /dev/usbmon memory to user space, and
overwrites it with arbitrary data, which causes all kinds of issues.

Return an -EPERM error from mon_bin_mmap() if the flag VM_WRTIE is set.
Also clear VM_MAYWRITE to make it impossible to change it to writable
later.

Cc: "Dmitry Vyukov" <dvyukov@google.com>
Cc: stable <stable@kernel.org>
Fixes: 6f23ee1fef ("USB: add binary API to usbmon")
Suggested-by: PaX Team <pageexec@freemail.hu>	# for the VM_MAYRITE portion
Link: https://syzkaller.appspot.com/bug?id=2eb1f35d6525fa4a74d75b4244971e5b1411c95a
Reported-by: syzbot+23f57c5ae902429285d7@syzkaller.appspotmail.com
Signed-off-by: Tadeusz Struk <tadeusz.struk@linaro.org>
Link: https://lore.kernel.org/r/20220919215957.205681-1-tadeusz.struk@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-22 15:52:29 +02:00
..
Kconfig docs: usb: rename files to .rst and add them to drivers-api 2019-06-20 14:28:36 +02:00
Makefile USB: add SPDX identifiers to all remaining Makefiles 2017-11-07 15:53:48 +01:00
mon_bin.c usb: mon: make mmapped memory read only 2022-09-22 15:52:29 +02:00
mon_main.c
mon_stat.c
mon_text.c USB: mon: Use scnprintf() for avoiding potential buffer overflow 2020-03-12 09:49:28 +01:00
usb_mon.h