Minimal supplement to upstream Kernel Self Protection Project changes. Features already provided by SELinux + Yama and archs other than multiarch arm64 / x86_64 aren't in scope. Only tags have stable history. Shared IRC channel with KSPP: irc.libera.chat #linux-hardening
aed6105b28
For historical reasons, the function drm_wait_vblank_ioctl always return -EINVAL if something gets wrong. This scenario limits the flexibility for the userspace to make detailed verification of any problem and take some action. In particular, the validation of “if (!dev->irq_enabled)” in the drm_wait_vblank_ioctl is responsible for checking if the driver support vblank or not. If the driver does not support VBlank, the function drm_wait_vblank_ioctl returns EINVAL, which does not represent the real issue; this patch changes this behavior by return EOPNOTSUPP. Additionally, drm_crtc_get_sequence_ioctl and drm_crtc_queue_sequence_ioctl, also returns EINVAL if vblank is not supported; this patch also changes the return value to EOPNOTSUPP in these functions. Lastly, these functions are invoked by libdrm, which is used by many compositors; because of this, it is important to check if this change breaks any compositor. In this sense, the following projects were examined: * Drm-hwcomposer * Kwin * Sway * Wlroots * Wayland * Weston * Mutter * Xorg (67 different drivers) For each repository the verification happened in three steps: * Update the main branch * Look for any occurrence of "drmCrtcQueueSequence", "drmCrtcGetSequence", and "drmWaitVBlank" with the command git grep -n "STRING". * Look in the git history of the project with the command git log -S<STRING> None of the above projects validate the use of EINVAL when using drmWaitVBlank(), which make safe, at least for these projects, to change the return values. On the other hand, mesa and xserver project uses drmCrtcQueueSequence() and drmCrtcGetSequence(); this change is harmless for both projects. Change since V5 (Pekka Paalanen): - Check if the change also affects Mutter Change since V4 (Daniel): - Also return EOPNOTSUPP in drm_crtc_[get|queue]_sequence_ioctl Change since V3: - Return EINVAL for _DRM_VBLANK_SIGNAL (Daniel) Change since V2: Daniel Vetter and Chris Wilson - Replace ENOTTY by EOPNOTSUPP - Return EINVAL if the parameters are wrong Cc: Keith Packard <keithp@keithp.com> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Pekka Paalanen <pekka.paalanen@collabora.com> Signed-off-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com> Reviewed-by: Daniel Vetter <daniel@ffwll.ch> Acked-by: Pekka Paalanen <pekka.paalanen@collabora.com> Link: https://patchwork.freedesktop.org/patch/msgid/20191002140516.adeyj3htylimmlmg@smtp.gmail.com |
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| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| 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 | ||
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| 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.