[v2,4/9] serial: mxs-auart: Fix out-of-bounds access through serial port index

Message ID 1519393117-31998-5-git-send-email-geert+renesas@glider.be
State New
Headers show
Series
  • serial: Fix out-of-bounds accesses through DT aliases
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Commit Message

Geert Uytterhoeven Feb. 23, 2018, 1:38 p.m.
The auart_port[] array is indexed using a value derived from the
"serialN" alias in DT, or from platform data, which may lead to an
out-of-bounds access.

Fix this by adding a range check.

Fixes: 1ea6607d4cdc9179 ("serial: mxs-auart: Allow device tree probing")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
v2:
  - Fix Fixes reference,
  - Use ARRAY_SIZE(),
  - Update patch description for platform data.
---
 drivers/tty/serial/mxs-auart.c | 4 ++++
 1 file changed, 4 insertions(+)

Patch

diff --git a/drivers/tty/serial/mxs-auart.c b/drivers/tty/serial/mxs-auart.c
index 079dc47aa142d8e1..caa8a41b6e71df9e 100644
--- a/drivers/tty/serial/mxs-auart.c
+++ b/drivers/tty/serial/mxs-auart.c
@@ -1663,6 +1663,10 @@  static int mxs_auart_probe(struct platform_device *pdev)
 		s->port.line = pdev->id < 0 ? 0 : pdev->id;
 	else if (ret < 0)
 		return ret;
+	if (s->port.line >= ARRAY_SIZE(auart_port)) {
+		dev_err(&pdev->dev, "serial%d out of range\n", s->port.line);
+		return -EINVAL;
+	}
 
 	if (of_id) {
 		pdev->id_entry = of_id->data;