From: Dmitry Osipenko Date: Thu, 18 Aug 2022 20:33:08 +0000 (+0200) Subject: media: cedrus: Fix endless loop in cedrus_h265_skip_bits() X-Git-Tag: v5.15.79~899 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=e8e0a6f4b8a299a660a398bf0bae87704d0fd144;p=platform%2Fkernel%2Flinux-rpi.git media: cedrus: Fix endless loop in cedrus_h265_skip_bits() commit 91db7a3fc7fe670cf1770a398a43bb4a1f776bf1 upstream. The busy status bit may never de-assert if number of programmed skip bits is incorrect, resulting in a kernel hang because the bit is polled endlessly in the code. Fix it by adding timeout for the bit-polling. This problem is reproducible by setting the data_bit_offset field of the HEVC slice params to a wrong value by userspace. Cc: stable@vger.kernel.org Fixes: 7678c5462680 (media: cedrus: Fix decoding for some HEVC videos) Reported-by: Nicolas Dufresne Signed-off-by: Dmitry Osipenko Signed-off-by: Nicolas Dufresne Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/staging/media/sunxi/cedrus/cedrus_h265.c b/drivers/staging/media/sunxi/cedrus/cedrus_h265.c index 830cae0..f2d9603 100644 --- a/drivers/staging/media/sunxi/cedrus/cedrus_h265.c +++ b/drivers/staging/media/sunxi/cedrus/cedrus_h265.c @@ -234,8 +234,9 @@ static void cedrus_h265_skip_bits(struct cedrus_dev *dev, int num) cedrus_write(dev, VE_DEC_H265_TRIGGER, VE_DEC_H265_TRIGGER_FLUSH_BITS | VE_DEC_H265_TRIGGER_TYPE_N_BITS(tmp)); - while (cedrus_read(dev, VE_DEC_H265_STATUS) & VE_DEC_H265_STATUS_VLD_BUSY) - udelay(1); + + if (cedrus_wait_for(dev, VE_DEC_H265_STATUS, VE_DEC_H265_STATUS_VLD_BUSY)) + dev_err_ratelimited(dev->dev, "timed out waiting to skip bits\n"); count += tmp; }