From 369ff955a8497988d079c4e3fa1e93c2570c1c69 Mon Sep 17 00:00:00 2001 From: Prasad J Pandit Date: Fri, 15 May 2020 01:36:08 +0530 Subject: [PATCH] es1370: check total frame count against current frame A guest user may set channel frame count via es1370_write() such that, in es1370_transfer_audio(), total frame count 'size' is lesser than the number of frames that are processed 'cnt'. int cnt = d->frame_cnt >> 16; int size = d->frame_cnt & 0xffff; if (size < cnt), it results in incorrect calculations leading to OOB access issue(s). Add check to avoid it. Reported-by: Ren Ding Reported-by: Hanqing Zhao Signed-off-by: Prasad J Pandit Message-id: 20200514200608.1744203-1-ppandit@redhat.com Signed-off-by: Gerd Hoffmann Upstream-Status: Backport [https://lists.gnu.org/archive/html/qemu-devel/2020-05/msg03983.html] CVE: CVE-2020-13361 Signed-off-by: Chee Yang Lee --- hw/audio/es1370.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/hw/audio/es1370.c b/hw/audio/es1370.c index 89c4dabcd44..5f8a83ff562 100644 --- a/hw/audio/es1370.c +++ b/hw/audio/es1370.c @@ -643,6 +643,9 @@ static void es1370_transfer_audio (ES1370State *s, struct chan *d, int loop_sel, int csc_bytes = (csc + 1) << d->shift; int cnt = d->frame_cnt >> 16; int size = d->frame_cnt & 0xffff; + if (size < cnt) { + return; + } int left = ((size - cnt + 1) << 2) + d->leftover; int transferred = 0; int temp = MIN (max, MIN (left, csc_bytes)); @@ -651,7 +654,7 @@ static void es1370_transfer_audio (ES1370State *s, struct chan *d, int loop_sel, addr += (cnt << 2) + d->leftover; if (index == ADC_CHANNEL) { - while (temp) { + while (temp > 0) { int acquired, to_copy; to_copy = MIN ((size_t) temp, sizeof (tmpbuf)); @@ -669,7 +672,7 @@ static void es1370_transfer_audio (ES1370State *s, struct chan *d, int loop_sel, else { SWVoiceOut *voice = s->dac_voice[index]; - while (temp) { + while (temp > 0) { int copied, to_copy; to_copy = MIN ((size_t) temp, sizeof (tmpbuf));