avcodec/pnm: Optimize reading loop in pnm_get()

Fixes: Timeout 13149 (5sec -> 3sec), 13166 (11sec -> 7sec), 13430 (5sec -> 3sec)
Fixes: 13149/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_PGM_fuzzer-5760833622114304
Fixes: 13166/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_PGMYUV_fuzzer-5763216322330624
Fixes: 13430/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_PPM_fuzzer-5758658334425088

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Michael Niedermayer 2019-03-10 22:39:53 +01:00
parent f20760fadb
commit 14eea7c47a

View File

@ -52,12 +52,13 @@ static void pnm_get(PNMContext *sc, char *str, int buf_size)
}
s = str;
while (bs < end && !pnm_space(c)) {
if ((s - str) < buf_size - 1)
*s++ = c;
while (bs < end && !pnm_space(c) && (s - str) < buf_size - 1) {
*s++ = c;
c = *bs++;
}
*s = '\0';
while (bs < end && !pnm_space(c))
c = *bs++;
sc->bytestream = bs;
}