diff options
Diffstat (limited to 'libre/sdl/SDL-1.2.15-CVE-2019-7577-Fix-a-buffer-overread-in-MS_ADPCM_deco.patch')
-rw-r--r-- | libre/sdl/SDL-1.2.15-CVE-2019-7577-Fix-a-buffer-overread-in-MS_ADPCM_deco.patch | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/libre/sdl/SDL-1.2.15-CVE-2019-7577-Fix-a-buffer-overread-in-MS_ADPCM_deco.patch b/libre/sdl/SDL-1.2.15-CVE-2019-7577-Fix-a-buffer-overread-in-MS_ADPCM_deco.patch new file mode 100644 index 000000000..23cbf9819 --- /dev/null +++ b/libre/sdl/SDL-1.2.15-CVE-2019-7577-Fix-a-buffer-overread-in-MS_ADPCM_deco.patch @@ -0,0 +1,75 @@ +From ac3d0d365b1f01a6782565feda0c7432a5795671 Mon Sep 17 00:00:00 2001 +From: =?UTF-8?q?Petr=20P=C3=ADsa=C5=99?= <ppisar@redhat.com> +Date: Thu, 14 Feb 2019 14:12:22 +0100 +Subject: [PATCH] CVE-2019-7577: Fix a buffer overread in MS_ADPCM_decode +MIME-Version: 1.0 +Content-Type: text/plain; charset=UTF-8 +Content-Transfer-Encoding: 8bit + +If RIFF/WAV data chunk length is shorter then expected for an audio +format defined in preceeding RIFF/WAV format headers, a buffer +overread can happen. + +This patch fixes it by checking a MS ADPCM data to be decoded are not +past the initialized buffer. + +CVE-2019-7577 +Reproducer: https://bugzilla.libsdl.org/show_bug.cgi?id=4492 + +Signed-off-by: Petr Písař <ppisar@redhat.com> +--- + src/audio/SDL_wave.c | 10 +++++++++- + 1 file changed, 9 insertions(+), 1 deletion(-) + +diff --git a/src/audio/SDL_wave.c b/src/audio/SDL_wave.c +index b4ad6c7..e42d01c 100644 +--- a/src/audio/SDL_wave.c ++++ b/src/audio/SDL_wave.c +@@ -115,7 +115,7 @@ static Sint32 MS_ADPCM_nibble(struct MS_ADPCM_decodestate *state, + static int MS_ADPCM_decode(Uint8 **audio_buf, Uint32 *audio_len) + { + struct MS_ADPCM_decodestate *state[2]; +- Uint8 *freeable, *encoded, *decoded; ++ Uint8 *freeable, *encoded, *encoded_end, *decoded; + Sint32 encoded_len, samplesleft; + Sint8 nybble, stereo; + Sint16 *coeff[2]; +@@ -124,6 +124,7 @@ static int MS_ADPCM_decode(Uint8 **audio_buf, Uint32 *audio_len) + /* Allocate the proper sized output buffer */ + encoded_len = *audio_len; + encoded = *audio_buf; ++ encoded_end = encoded + encoded_len; + freeable = *audio_buf; + *audio_len = (encoded_len/MS_ADPCM_state.wavefmt.blockalign) * + MS_ADPCM_state.wSamplesPerBlock* +@@ -141,6 +142,7 @@ static int MS_ADPCM_decode(Uint8 **audio_buf, Uint32 *audio_len) + state[1] = &MS_ADPCM_state.state[stereo]; + while ( encoded_len >= MS_ADPCM_state.wavefmt.blockalign ) { + /* Grab the initial information for this block */ ++ if (encoded + 7 + (stereo ? 7 : 0) > encoded_end) goto too_short; + state[0]->hPredictor = *encoded++; + if ( stereo ) { + state[1]->hPredictor = *encoded++; +@@ -188,6 +190,8 @@ static int MS_ADPCM_decode(Uint8 **audio_buf, Uint32 *audio_len) + samplesleft = (MS_ADPCM_state.wSamplesPerBlock-2)* + MS_ADPCM_state.wavefmt.channels; + while ( samplesleft > 0 ) { ++ if (encoded + 1 > encoded_end) goto too_short; ++ + nybble = (*encoded)>>4; + new_sample = MS_ADPCM_nibble(state[0],nybble,coeff[0]); + decoded[0] = new_sample&0xFF; +@@ -209,6 +213,10 @@ static int MS_ADPCM_decode(Uint8 **audio_buf, Uint32 *audio_len) + } + SDL_free(freeable); + return(0); ++too_short: ++ SDL_SetError("Too short chunk for a MS ADPCM decoder"); ++ SDL_free(freeable); ++ return(-1); + } + + struct IMA_ADPCM_decodestate { +-- +2.20.1 + |