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avcodec/jpeg2000htdec: check if block decoding will exceed internal precision 

Intended to replace https://patchwork.ffmpeg.org/project/ffmpeg/patch/20230802000135.26482-3-michael@niedermayer.cc/
with a more accurate block decoding magnitude bound.

Fixes: 62433/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_JPEG2000_fuzzer-5828618092937216
Fixes: 58299/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_JPEG2000_fuzzer-5828618092937216
Previous-version-reviewed-by: Tomas Härdin <git@haerdin.se>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Pierre-Anthony Lemieux 2023-08-12 13:31:16 -07:00 committed by Michael Niedermayer
parent aa1e768120
commit a1384b4e86
No known key found for this signature in database
GPG Key ID: B18E8928B3948D64
1 changed files with 36 additions and 6 deletions
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42
libavcodec/jpeg2000htdec.c
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@ -567,11 +567,19 @@ static int jpeg2000_decode_ht_cleanup_segment(const Jpeg2000DecoderContext *s,
uint64_t c;
uint8_t *sigma;
uint32_t *mu;
uint8_t *sigma, *sigma_n, *E;
uint32_t *mu, *mu_n;
const uint8_t *vlc_buf = Dcup + Pcup;
/*
* Bound on the precision needed to process the codeblock. The number of
* decoded bit planes is equal to at most cblk->zbp + 2 since S_blk = P if
* there are no placeholder passes or HT Sets and P = cblk->zbp. See Rec.
* ITU-T T.814, 7.6.
*/
int maxbp = cblk->zbp + 2;
/* convert to raster-scan */
const uint16_t is_border_x = width % 2;
const uint16_t is_border_y = height % 2;
@ -581,9 +589,13 @@ static int jpeg2000_decode_ht_cleanup_segment(const Jpeg2000DecoderContext *s,
size_t buf_size = 4 * quad_width * quad_height;
uint8_t *sigma_n = av_calloc(buf_size, sizeof(uint8_t));
uint8_t *E = av_calloc(buf_size, sizeof(uint8_t));
uint32_t *mu_n = av_calloc(buf_size, sizeof(uint32_t));
/* do we have enough precision, assuming a 32-bit decoding path */
if (maxbp >= 32)
return AVERROR_INVALIDDATA;
sigma_n = av_calloc(buf_size, sizeof(uint8_t));
E = av_calloc(buf_size, sizeof(uint8_t));
mu_n = av_calloc(buf_size, sizeof(uint32_t));
if (!sigma_n || !E || !mu_n) {
ret = AVERROR(ENOMEM);
@ -676,6 +688,10 @@ static int jpeg2000_decode_ht_cleanup_segment(const Jpeg2000DecoderContext *s,
}
U[J2K_Q1] = kappa[J2K_Q1] + u[J2K_Q1];
U[J2K_Q2] = kappa[J2K_Q2] + u[J2K_Q2];
if (U[J2K_Q1] > maxbp || U[J2K_Q2] > maxbp) {
ret = AVERROR_INVALIDDATA;
goto free;
}
for (int i = 0; i < 4; i++) {
m[J2K_Q1][i] = sigma_n[4 * q1 + i] * U[J2K_Q1] - ((emb_pat_k[J2K_Q1] >> i) & 1);
@ -713,6 +729,10 @@ static int jpeg2000_decode_ht_cleanup_segment(const Jpeg2000DecoderContext *s,
}
U[J2K_Q1] = kappa[J2K_Q1] + u[J2K_Q1];
if (U[J2K_Q1] > maxbp) {
ret = AVERROR_INVALIDDATA;
goto free;
}
for (int i = 0; i < 4; i++)
m[J2K_Q1][i] = sigma_n[4 * q1 + i] * U[J2K_Q1] - ((emb_pat_k[J2K_Q1] >> i) & 1);
@ -842,6 +862,10 @@ static int jpeg2000_decode_ht_cleanup_segment(const Jpeg2000DecoderContext *s,
U[J2K_Q1] = kappa[J2K_Q1] + u[J2K_Q1];
U[J2K_Q2] = kappa[J2K_Q2] + u[J2K_Q2];
if (U[J2K_Q1] > maxbp || U[J2K_Q2] > maxbp) {
ret = AVERROR_INVALIDDATA;
goto free;
}
for (int i = 0; i < 4; i++) {
m[J2K_Q1][i] = sigma_n[4 * q1 + i] * U[J2K_Q1] - ((emb_pat_k[J2K_Q1] >> i) & 1);
@ -910,6 +934,10 @@ static int jpeg2000_decode_ht_cleanup_segment(const Jpeg2000DecoderContext *s,
kappa[J2K_Q1] = FFMAX(1, gamma[J2K_Q1] * (max_e[J2K_Q1] - 1));
U[J2K_Q1] = kappa[J2K_Q1] + u[J2K_Q1];
if (U[J2K_Q1] > maxbp) {
ret = AVERROR_INVALIDDATA;
goto free;
}
for (int i = 0; i < 4; i++)
m[J2K_Q1][i] = sigma_n[4 * q1 + i] * U[J2K_Q1] - ((emb_pat_k[J2K_Q1] >> i) & 1);
@ -1238,8 +1266,10 @@ ff_jpeg2000_decode_htj2k(const Jpeg2000DecoderContext *s, Jpeg2000CodingStyle *c
}
if ((ret = jpeg2000_decode_ht_cleanup_segment(s, cblk, t1, &mel_state, &mel, &vlc,
&mag_sgn, Dcup, Lcup, Pcup, pLSB, width,
height, sample_buf, block_states)) < 0)
height, sample_buf, block_states)) < 0) {
av_log(s->avctx, AV_LOG_ERROR, "Bad HT cleanup segment\n");
goto free;
}
if (cblk->npasses > 1)
jpeg2000_decode_sigprop_segment(cblk, width, height, Dref, Lref,