| Message ID | 20190612232020.25959-4-michael@niedermayer.cc |
|---|---|
| State | New |
| Headers | show |
On Thu, Jun 13, 2019 at 01:20:20 +0200, Michael Niedermayer wrote:
> + if (header->data_min == header->data_max) {
Just a note:
Equality comparison of floats/doubles may trigger a warning. (Possibly
needs to be explicitly enabled though, like with "-Wfloat-equal" on
gcc.) Might be okay though nevertheless.
Moritz
On Thu, Jun 13, 2019 at 04:29:54PM +0200, Moritz Barsnick wrote: > On Thu, Jun 13, 2019 at 01:20:20 +0200, Michael Niedermayer wrote: > > + if (header->data_min == header->data_max) { > > Just a note: > Equality comparison of floats/doubles may trigger a warning. (Possibly > needs to be explicitly enabled though, like with "-Wfloat-equal" on > gcc.) Might be okay though nevertheless. ill post a new patch that reorders this a bit, maybe it doesnt generate a warning. But using something like DBL_EPSILON is more wrong than the == here i think, as it could turn a non blank image into a blank one thx [...]
diff --git a/libavcodec/fitsdec.c b/libavcodec/fitsdec.c index b0753813c9..2da79e1ef9 100644 --- a/libavcodec/fitsdec.c +++ b/libavcodec/fitsdec.c @@ -168,6 +168,16 @@ static int fits_read_header(AVCodecContext *avctx, const uint8_t **ptr, FITSHead header->data_min = (header->data_min - header->bzero) / header->bscale; header->data_max = (header->data_max - header->bzero) / header->bscale; } + if (!header->rgb) { + if (header->data_min > header->data_max) { + av_log(avctx, AV_LOG_ERROR, "data min/max (%g %g) is invalid\n", header->data_min, header->data_max); + return AVERROR_INVALIDDATA; + } + if (header->data_min == header->data_max) { + av_log(avctx, AV_LOG_WARNING, "data min/max indicates a blank image\n"); + header->data_max ++; + } + } return 0; }
Fixes: division by 0 Fixes: 15206/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_FITS_fuzzer-5657260212092928 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> --- libavcodec/fitsdec.c | 10 ++++++++++ 1 file changed, 10 insertions(+)