linux/drivers/tee
Jens Wiklander 573ae4f13f tee: add overflow check in register_shm_helper()
With special lengths supplied by user space, register_shm_helper() has
an integer overflow when calculating the number of pages covered by a
supplied user space memory region.

This causes internal_get_user_pages_fast() a helper function of
pin_user_pages_fast() to do a NULL pointer dereference:

  Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010
  Modules linked in:
  CPU: 1 PID: 173 Comm: optee_example_a Not tainted 5.19.0 #11
  Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015
  pc : internal_get_user_pages_fast+0x474/0xa80
  Call trace:
   internal_get_user_pages_fast+0x474/0xa80
   pin_user_pages_fast+0x24/0x4c
   register_shm_helper+0x194/0x330
   tee_shm_register_user_buf+0x78/0x120
   tee_ioctl+0xd0/0x11a0
   __arm64_sys_ioctl+0xa8/0xec
   invoke_syscall+0x48/0x114

Fix this by adding an an explicit call to access_ok() in
tee_shm_register_user_buf() to catch an invalid user space address
early.

Fixes: 033ddf12bc ("tee: add register user memory")
Cc: stable@vger.kernel.org
Reported-by: Nimish Mishra <neelam.nimish@gmail.com>
Reported-by: Anirban Chakraborty <ch.anirban00727@gmail.com>
Reported-by: Debdeep Mukhopadhyay <debdeep.mukhopadhyay@gmail.com>
Suggested-by: Jerome Forissier <jerome.forissier@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-08-18 09:20:27 -07:00
..
amdtee TEE shared memory cleanup for v5.18 2022-02-25 17:05:11 +01:00
optee optee: Remove duplicate 'of' in two places. 2022-07-08 10:51:24 +02:00
Kconfig tee: combine "config" and "menu" for TEE's menuconfig 2022-04-05 07:32:23 +02:00
Makefile tee: add AMD-TEE driver 2020-01-04 13:49:51 +08:00
tee_core.c tee: tee_get_drvdata(): fix description of return value 2022-07-08 10:51:24 +02:00
tee_private.h tee: add tee_shm_register_{user,kernel}_buf() 2022-02-16 07:49:41 +01:00
tee_shm_pool.c tee: refactor TEE_SHM_* flags 2022-02-16 07:49:41 +01:00
tee_shm.c tee: add overflow check in register_shm_helper() 2022-08-18 09:20:27 -07:00