From a2cd86a94a881b38a7d8bb67c61920ab3b23e82d Mon Sep 17 00:00:00 2001 From: Philippe Mathieu-Daudé Date: Wed, 16 Jun 2021 12:43:49 +0200 Subject: hw/audio/sb16: Avoid assertion by restricting I/O sampling rate range MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit While the SB16 seems to work up to 48000 Hz, the "Sound Blaster Series Hardware Programming Guide" limit the sampling range from 4000 Hz to 44100 Hz (Section 3-9, 3-10: Digitized Sound I/O Programming, tables 3-2 and 3-3). Later, section 6-15 (DSP Commands) is more specific regarding the 41h / 42h registers (Set digitized sound output sampling rate): Valid sampling rates range from 5000 to 45000 Hz inclusive. There is no comment regarding error handling if the register is filled with an out-of-range value. (See also section 3-28 "8-bit or 16-bit Auto-initialize Transfer"). Assume limits are enforced in hardware. This fixes triggering an assertion in audio_calloc(): #1 abort #2 audio_bug audio/audio.c:119:9 #3 audio_calloc audio/audio.c:154:9 #4 audio_pcm_sw_alloc_resources_out audio/audio_template.h:116:15 #5 audio_pcm_sw_init_out audio/audio_template.h:175:11 #6 audio_pcm_create_voice_pair_out audio/audio_template.h:410:9 #7 AUD_open_out audio/audio_template.h:503:14 #8 continue_dma8 hw/audio/sb16.c:216:20 #9 dma_cmd8 hw/audio/sb16.c:276:5 #10 command hw/audio/sb16.c:0 #11 dsp_write hw/audio/sb16.c:949:13 #12 portio_write softmmu/ioport.c:205:13 #13 memory_region_write_accessor softmmu/memory.c:491:5 #14 access_with_adjusted_size softmmu/memory.c:552:18 #15 memory_region_dispatch_write softmmu/memory.c:0:13 #16 flatview_write_continue softmmu/physmem.c:2759:23 #17 flatview_write softmmu/physmem.c:2799:14 #18 address_space_write softmmu/physmem.c:2891:18 #19 cpu_outw softmmu/ioport.c:70:5 [*] http://www.baudline.com/solutions/full_duplex/sb16_pci/index.html OSS-Fuzz Report: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=29174 Fixes: 85571bc7415 ("audio merge (malc)") Buglink: https://bugs.launchpad.net/bugs/1910603 Tested-by: Qiang Liu Reviewed-by: Qiang Liu Signed-off-by: Philippe Mathieu-Daudé Message-Id: <20210616104349.2398060-1-f4bug@amsat.org> Signed-off-by: Gerd Hoffmann --- hw/audio/sb16.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 'hw/audio/sb16.c') diff --git a/hw/audio/sb16.c b/hw/audio/sb16.c index 8b20700410..5cf121fe36 100644 --- a/hw/audio/sb16.c +++ b/hw/audio/sb16.c @@ -115,6 +115,9 @@ struct SB16State { PortioList portio_list; }; +#define SAMPLE_RATE_MIN 5000 +#define SAMPLE_RATE_MAX 45000 + static void SB_audio_callback (void *opaque, int free); static int magic_of_irq (int irq) @@ -241,6 +244,17 @@ static void dma_cmd8 (SB16State *s, int mask, int dma_len) int tmp = (256 - s->time_const); s->freq = (1000000 + (tmp / 2)) / tmp; } + if (s->freq < SAMPLE_RATE_MIN) { + qemu_log_mask(LOG_GUEST_ERROR, + "sampling range too low: %d, increasing to %u\n", + s->freq, SAMPLE_RATE_MIN); + s->freq = SAMPLE_RATE_MIN; + } else if (s->freq > SAMPLE_RATE_MAX) { + qemu_log_mask(LOG_GUEST_ERROR, + "sampling range too high: %d, decreasing to %u\n", + s->freq, SAMPLE_RATE_MAX); + s->freq = SAMPLE_RATE_MAX; + } if (dma_len != -1) { s->block_size = dma_len << s->fmt_stereo; -- cgit 1.4.1