Jason Gunthorpe jgg@ziepe.ca wrote:
On Fri, Oct 09, 2020 at 03:04:20PM -0700, Andrew Morton wrote:
On Fri, 9 Oct 2020 17:03:37 +0200 "Christian König" ckoenig.leichtzumerken@gmail.com wrote:
Patch "495c10cc1c0c CHROMIUM: dma-buf: restore args..." adds a workaround for a bug in mmap_region.
As the comment states ->mmap() callback can change vma->vm_file and so we might call fput() on the wrong file.
Revert the workaround and proper fix this in mmap_region.
Doesn't this patch series address the same thing as https://lkml.kernel.org/r/20200916090733.31427-1-linmiaohe@huawei.com?
Same basic issue, looks like both of these patches should be combined to plug it fully.
Jason
I think so too. Both of these patches fix the fput at possible wrong @file due to ->mmap() callback can change vma->vm_file.