4.19-stable review patch. If anyone has any objections, please let me know.
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[ 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 tvrtko.ursulin@intel.com Fixes: 5c4604e757ba ("drm/i915: Prevent a race during I915_GEM_MMAP ioctl with WC set") Reported-by: Guenter Roeck linux@roeck-us.net Cc: Adam Zabrocki adamza@microsoft.com Cc: Joonas Lahtinen joonas.lahtinen@linux.intel.com Cc: stable@vger.kernel.org # v4.0+ Cc: Akash Goel akash.goel@intel.com Cc: Chris Wilson chris@chris-wilson.co.uk Cc: Jani Nikula jani.nikula@linux.intel.com Cc: Rodrigo Vivi rodrigo.vivi@intel.com Cc: intel-gfx@lists.freedesktop.org Reviewed-by: Chris Wilson chris@chris-wilson.co.uk Link: https://patchwork.freedesktop.org/patch/msgid/20190305110409.28633-1-tvrtko.... (cherry picked from commit a90e1948efb648f567444f87f3c19b2a0787affd) Signed-off-by: Rodrigo Vivi rodrigo.vivi@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- 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); }
/**