[PATCH 0/6] treewide: test clock rate to avoid division by 0

[PATCH 0/6] treewide: test clock rate to avoid division by 0

[Wolfram Sang]

Here is the outcome of researching if the result of clk_get_rate() was directly
used as a divisor without checking if it is 0. Inspired by a Coverity report.

Wolfram Sang (6):
  ide: palm_bk3710: test clock rate to avoid division by 0
  net: ethernet: renesas: ravb_main: test clock rate to avoid division
    by 0
  pwm: pwm-img: test clock rate to avoid division by 0
  pwm: pwm-lpc18xx-sct: test clock rate to avoid division by 0
  watchdog: atlas7_wdt: test clock rate to avoid division by 0
  watchdog: tangox_wdt: test clock rate to avoid division by 0

 drivers/ide/palm_bk3710.c                | 2 ++
 drivers/net/ethernet/renesas/ravb_main.c | 3 +++
 drivers/pwm/pwm-img.c                    | 5 +++++
 drivers/pwm/pwm-lpc18xx-sct.c            | 2 ++
 drivers/watchdog/atlas7_wdt.c            | 5 +++++
 drivers/watchdog/tangox_wdt.c            | 2 ++
 6 files changed, 19 insertions(+)

-- 
2.7.0

[PATCH 1/6] ide: palm_bk3710: test clock rate to avoid division by 0

[Wolfram Sang]

From: Wolfram Sang <wsa+renesas@sang-engineering.com>

The clk API may return 0 on clk_get_rate, so we should check the result before
using it as a divisor.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---

Should go individually via subsystem tree.

 drivers/ide/palm_bk3710.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/ide/palm_bk3710.c b/drivers/ide/palm_bk3710.c
index 8012e43bf8f618..46427ea01753b4 100644
--- a/drivers/ide/palm_bk3710.c
+++ b/drivers/ide/palm_bk3710.c
@@ -325,6 +325,8 @@ static int __init palm_bk3710_probe(struct platform_device *pdev)
 
 	clk_enable(clk);
 	rate = clk_get_rate(clk);
+	if (!rate)
+		return -EINVAL;
 
 	/* NOTE:  round *down* to meet minimum timings; we count in clocks */
 	ideclk_period = 1000000000UL / rate;
-- 
2.7.0