7.3-stable review patch. If anyone has any objections, please let me know. ------------------ From: Denis Arefev [ Upstream commit fd65108f5001ffb416dc9bd37ec1893f55cff24a ] ins->code.offset and code->size are measured in 32-bit words, while DSP_CODE_BYTE_SIZE is the size of the DSP code area in bytes. The check ins->code.offset + code->size > DSP_CODE_BYTE_SIZE in cs46xx_dsp_load_module() therefore allowed up to four times more code than the code area can hold. The shadow buffer ins->code.data is allocated with kmalloc(DSP_CODE_BYTE_SIZE), i.e. it holds DSP_CODE_BYTE_SIZE/4 words. A firmware file with a code segment larger than DSP_CODE_BYTE_SIZE/4 words (28 KiB) passed the check and caused an out-of-bounds write in shadow_and_reallocate_code() and an out-of-bounds read in snd_cs46xx_download(). Compare the sum in words against DSP_CODE_BYTE_SIZE/4 and cast it to u64 so that the sum cannot wrap for large code->size values. Found by Linux Verification Center (linuxtesting.org) with SVACE. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Signed-off-by: Denis Arefev Link: https://patch.msgid.link/20261014102619.16415-1-arefev@swemel.ru Signed-off-by: Takashi Iwai Signed-off-by: Sasha Levin --- sound/pci/cs46xx/dsp_spos.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/sound/pci/cs46xx/dsp_spos.c b/sound/pci/cs46xx/dsp_spos.c index 6fd4f629d1d57..a77e6f5a14ada 100644 --- a/sound/pci/cs46xx/dsp_spos.c +++ b/sound/pci/cs46xx/dsp_spos.c @@ -393,7 +393,7 @@ int cs46xx_dsp_load_module (struct snd_cs46xx * chip, struct dsp_module_desc * m dev_dbg(chip->card->dev, "dsp_spos: module got no code segment\n"); } else { - if (ins->code.offset + code->size > DSP_CODE_BYTE_SIZE) { + if ((u64)ins->code.offset + code->size > DSP_CODE_BYTE_SIZE / 4) { dev_err(chip->card->dev, "dsp_spos: no space available in DSP\n"); return -ENOMEM; -- 2.53.0