573ae4f13f
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:
|
||
|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| io_uring | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.