diff options
| author | Todd Kjos <tkjos@android.com> | 2019-06-05 09:37:45 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-06-09 09:18:20 +0200 |
| commit | 046f1166fb7ed28e064b24c666aa7312e1d75a0e (patch) | |
| tree | 2e5c309a8ac50f7d33c2faa05474174644868e58 /drivers/android | |
| parent | 0e984ff3e1559579c289e9c918d573e5b721ab5c (diff) | |
Revert "binder: fix handling of misaligned binder object"
This reverts commit 33c6b9ca70a8b066a613e2a3d0331ae8f82aa31a.
The commit message is for a different patch. Reverting and then adding
the same patch back with the correct commit message.
Reported-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Cc: stable <stable@vger.kernel.org> # 4.14
Signed-off-by: Todd Kjos <tkjos@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/android')
| -rw-r--r-- | drivers/android/binder_alloc.c | 18 |
1 files changed, 10 insertions, 8 deletions
diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c index e0b0399ff7ec..b9281f2725a6 100644 --- a/drivers/android/binder_alloc.c +++ b/drivers/android/binder_alloc.c @@ -945,13 +945,14 @@ enum lru_status binder_alloc_free_page(struct list_head *item, index = page - alloc->pages; page_addr = (uintptr_t)alloc->buffer + index * PAGE_SIZE; - - mm = alloc->vma_vm_mm; - if (!mmget_not_zero(mm)) - goto err_mmget; - if (!down_write_trylock(&mm->mmap_sem)) - goto err_down_write_mmap_sem_failed; vma = binder_alloc_get_vma(alloc); + if (vma) { + if (!mmget_not_zero(alloc->vma_vm_mm)) + goto err_mmget; + mm = alloc->vma_vm_mm; + if (!down_write_trylock(&mm->mmap_sem)) + goto err_down_write_mmap_sem_failed; + } list_lru_isolate(lru, item); spin_unlock(lock); @@ -964,9 +965,10 @@ enum lru_status binder_alloc_free_page(struct list_head *item, PAGE_SIZE); trace_binder_unmap_user_end(alloc, index); + + up_write(&mm->mmap_sem); + mmput(mm); } - up_write(&mm->mmap_sem); - mmput(mm); trace_binder_unmap_kernel_start(alloc, index); |