Messages in this thread Patch in this message | | | From | Laura Abbott <> | Subject | [PATCH] staging: android: ion: Switch to pr_warn_once in ion_buffer_destroy | Date | Mon, 14 May 2018 14:35:09 -0700 |
| |
Syzbot reported yet another warning with Ion:
WARNING: CPU: 0 PID: 1467 at drivers/staging/android/ion/ion.c:122 ion_buffer_destroy+0xd4/0x190 drivers/staging/android/ion/ion.c:122 Kernel panic - not syncing: panic_on_warn set ...
This is catching that a buffer was freed with an existing kernel mapping still present. This can be easily be triggered from userspace by calling DMA_BUF_SYNC_START without calling DMA_BUF_SYNC_END. Switch to a single pr_warn_once to indicate the error without being disruptive.
Reported-by: syzbot+cd8bcd40cb049efa2770@syzkaller.appspotmail.com Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Laura Abbott <labbott@redhat.com> --- drivers/staging/android/ion/ion.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/staging/android/ion/ion.c b/drivers/staging/android/ion/ion.c index e74db7902549..a68329411b29 100644 --- a/drivers/staging/android/ion/ion.c +++ b/drivers/staging/android/ion/ion.c @@ -114,8 +114,11 @@ static struct ion_buffer *ion_buffer_create(struct ion_heap *heap, void ion_buffer_destroy(struct ion_buffer *buffer) { - if (WARN_ON(buffer->kmap_cnt > 0)) + if (buffer->kmap_cnt > 0) { + pr_warn_once("%s: buffer still mapped in the kernel\n", + __func__); buffer->heap->ops->unmap_kernel(buffer->heap, buffer); + } buffer->heap->ops->free(buffer); kfree(buffer); } -- 2.17.0
| |