ASoC: SOF: Intel: hda: Fix potential buffer overflow by snprintf()

jira VULN-70503
cve CVE-2022-50050
commit-author Takashi Iwai <tiwai@suse.de>
commit 94c1ceb
upstream-diff |
	Adjusted context due to missing commit
	71778f7("ASoC: SOF: Intel: hda: Define rom_status_reg in sof_intel_dsp_desc")

snprintf() returns the would-be-filled size when the string overflows
the given buffer size, hence using this value may result in the buffer
overflow (although it's unrealistic).

This patch replaces with a safer version, scnprintf() for papering
over such a potential issue.

Fixes: 29c8e43 ("ASoC: SOF: Intel: hda: add extended rom status dump to error log")
	Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/20220801165420.25978-4-tiwai@suse.de
	Signed-off-by: Mark Brown <broonie@kernel.org>
(cherry picked from commit 94c1ceb)
	Signed-off-by: Roxana Nicolescu <rnicolescu@ciq.com>

Author: roxanan1996

sound/soc/sof/intel/hda.c

@@ -536,7 +536,7 @@ static void hda_dsp_dump_ext_rom_status(struct snd_sof_dev *sdev, u32 flags)
 
 	for (i = 0; i < HDA_EXT_ROM_STATUS_SIZE; i++) {
 		value = snd_sof_dsp_read(sdev, HDA_DSP_BAR, HDA_DSP_SRAM_REG_ROM_STATUS + i * 0x4);
-		len += snprintf(msg + len, sizeof(msg) - len, " 0x%x", value);
+		len += scnprintf(msg + len, sizeof(msg) - len, " 0x%x", value);
 	}
 
 	dev_err(sdev->dev, "extended rom status: %s", msg);