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From 00338325c4a2c5b0010462b21a4373cbb4341c9d Mon Sep 17 00:00:00 2001
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From: Stefan Weil <sw@weilnetz.de>
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Date: Sat, 1 Sep 2012 12:43:41 +0200
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Subject: [PATCH] lm4549: Fix buffer overflow
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Report from smatch:
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lm4549.c:234 lm4549_write_samples(14) error:
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buffer overflow 's->buffer' 1024 <= 1024
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There must be enough space to add two entries starting with index
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s->buffer_level, therefore the old check was wrong.
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[Peter Maydell <peter.maydell@linaro.org> clarifies the nature of the
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analyser warning:
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I don't object to making the change to placate the analyser,
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but I don't think this is actually a buffer overrun. We always
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add and remove samples from the buffer two at a time, so it's
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not possible to get here with s->buffer_level == BUFFER_SIZE-1
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(which is the only case where the old and new conditions
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give different answers).]
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Signed-off-by: Stefan Weil <sw@weilnetz.de>
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Signed-off-by: Stefan Hajnoczi <stefanha@gmail.com>
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(cherry picked from commit 8139626643cbe8dc07bd9acc88057effeedf8064)
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Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
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---
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hw/lm4549.c | 2 +-
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1 file changed, 1 insertion(+), 1 deletion(-)
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diff --git a/hw/lm4549.c b/hw/lm4549.c
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index 80b3ec4..e0137d5 100644
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--- a/hw/lm4549.c
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+++ b/hw/lm4549.c
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@@ -224,7 +224,7 @@ uint32_t lm4549_write_samples(lm4549_state *s, uint32_t left, uint32_t right)
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This model supports 16-bit playback.
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*/
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- if (s->buffer_level >= LM4549_BUFFER_SIZE) {
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+ if (s->buffer_level > LM4549_BUFFER_SIZE - 2) {
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DPRINTF("write_sample Buffer full\n");
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return 0;
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}
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--
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1.7.12.1
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