5cec2d2e58
An munmap() on a binder device causes binder_vma_close() to be called which clears the alloc->vma pointer. If direct reclaim causes binder_alloc_free_page() to be called, there is a race where alloc->vma is read into a local vma pointer and then used later after the mm->mmap_sem is acquired. This can result in calling zap_page_range() with an invalid vma which manifests as a use-after-free in zap_page_range(). The fix is to check alloc->vma after acquiring the mmap_sem (which we were acquiring anyway) and skip zap_page_range() if it has changed to NULL. Signed-off-by: Todd Kjos <tkjos@google.com> Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
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| .. | ||
| Kconfig | ||
| Makefile | ||
| binder.c | ||
| binder_alloc.c | ||
| binder_alloc.h | ||
| binder_alloc_selftest.c | ||
| binder_internal.h | ||
| binder_trace.h | ||
| binderfs.c | ||