archive mirror
 help / color / mirror / Atom feed
From: Andi Kleen <>
Cc:, Andi Kleen <>,,
Subject: [PATCH] Fix read buffer overflow in delta-ipc
Date: Thu, 21 Dec 2017 16:12:12 -0800	[thread overview]
Message-ID: <> (raw)

From: Andi Kleen <>

The single caller passes a string to delta_ipc_open, which copies with a
fixed size larger than the string. So it copies some random data after
the original string the ro segment.

If the string was at the end of a page it may fault.

Just copy the string with a normal strcpy after clearing the field.

Found by a LTO build (which errors out)
because the compiler inlines the functions and can resolve
the string sizes and triggers the compile time checks in memcpy.

In function ‘memcpy’,
    inlined from ‘delta_ipc_open.constprop’ at linux/drivers/media/platform/sti/delta/delta-ipc.c:178:0,
    inlined from ‘delta_mjpeg_ipc_open’ at linux/drivers/media/platform/sti/delta/delta-mjpeg-dec.c:227:0,
    inlined from ‘delta_mjpeg_decode’ at linux/drivers/media/platform/sti/delta/delta-mjpeg-dec.c:403:0:
/home/andi/lsrc/linux/include/linux/string.h:337:0: error: call to ‘__read_overflow2’ declared with attribute error: detected read beyond size of object passed as 2nd parameter

Signed-off-by: Andi Kleen <>
 drivers/media/platform/sti/delta/delta-ipc.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/media/platform/sti/delta/delta-ipc.c b/drivers/media/platform/sti/delta/delta-ipc.c
index 41e4a4c259b3..b6c256e3ceb6 100644
--- a/drivers/media/platform/sti/delta/delta-ipc.c
+++ b/drivers/media/platform/sti/delta/delta-ipc.c
@@ -175,8 +175,8 @@ int delta_ipc_open(struct delta_ctx *pctx, const char *name,
 	msg.ipc_buf_size = ipc_buf_size;
 	msg.ipc_buf_paddr = ctx->ipc_buf->paddr;
-	memcpy(, name, sizeof(;
-[sizeof( - 1] = 0;
+	memset(, 0, sizeof(;
+	strcpy(, name);
 	msg.param_size = param->size;
 	memcpy(ctx->ipc_buf->vaddr, param->data, msg.param_size);

             reply	other threads:[~2017-12-22  0:21 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-12-22  0:12 Andi Kleen [this message]
2018-01-03  9:40 ` Hugues FRUCHET
2018-01-04  0:19   ` Andi Kleen
2018-01-04  9:53     ` Hugues FRUCHET

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \ \ \ \ \ \ \ \
    --subject='Re: [PATCH] Fix read buffer overflow in delta-ipc' \

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).