diff options
| author | Laura Abbott <labbott@redhat.com> | 2018-05-14 14:35:09 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-06-16 09:52:33 +0200 |
| commit | 8da07ee9e433f3af74f126c5bfd1a1a44d0aaeef (patch) | |
| tree | 17155305c7b078b285836f82c63107a33fa5af5b | |
| parent | 838b0e900a7e16799dbecc031739de1ee40741af (diff) | |
staging: android: ion: Switch to pr_warn_once in ion_buffer_destroy
commit 45ad559a29629cb1c64ee636563c69b71524f077 upstream.
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>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/staging/android/ion/ion.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/staging/android/ion/ion.c b/drivers/staging/android/ion/ion.c index 209a8f7ef02b..6f9974cb0e15 100644 --- a/drivers/staging/android/ion/ion.c +++ b/drivers/staging/android/ion/ion.c @@ -192,8 +192,11 @@ err2: 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); vfree(buffer->pages); kfree(buffer); |