4.19-stable review patch. If anyone has any objections, please let me know.
------------------ [ Upstream commit ca22f32a6296cbfa29de56328c8505560a18cfa8 ] Legacy behaviour was to allow non-page-aligned mmap requests, as does the linux mmap(2) implementation by virtue of automatically rounding up for the caller. To avoid breaking legacy userspace relax the newly introduced fix. Signed-off-by: Tvrtko Ursulin <[email protected]> Fixes: 5c4604e757ba ("drm/i915: Prevent a race during I915_GEM_MMAP ioctl with WC set") Reported-by: Guenter Roeck <[email protected]> Cc: Adam Zabrocki <[email protected]> Cc: Joonas Lahtinen <[email protected]> Cc: <[email protected]> # v4.0+ Cc: Akash Goel <[email protected]> Cc: Chris Wilson <[email protected]> Cc: Jani Nikula <[email protected]> Cc: Rodrigo Vivi <[email protected]> Cc: [email protected] Reviewed-by: Chris Wilson <[email protected]> Link: https://patchwork.freedesktop.org/patch/msgid/[email protected] (cherry picked from commit a90e1948efb648f567444f87f3c19b2a0787affd) Signed-off-by: Rodrigo Vivi <[email protected]> Signed-off-by: Sasha Levin <[email protected]> --- drivers/gpu/drm/i915/i915_gem.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 280c851714e6..03cda197fb6b 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -1828,7 +1828,8 @@ __vma_matches(struct vm_area_struct *vma, struct file *filp, if (vma->vm_file != filp) return false; - return vma->vm_start == addr && (vma->vm_end - vma->vm_start) == size; + return vma->vm_start == addr && + (vma->vm_end - vma->vm_start) == PAGE_ALIGN(size); } /** -- 2.19.1

