Re: [PATCH][next] clk: ti: check for null return in strrchr to avoid null dereferencing

[Tero Kristo]

On 27/07/17 02:56, Colin King wrote:

From: Colin Ian King <colin.k...@canonical.com>

strrchr can potentially return a null so the following strlen on the
null pointer can cause a null dereference. Add a check to see if
the string postfix is not null before calling strlen.

Detected by CoverityScan, CID#1452039 ("Dereference null return")

Signed-off-by: Colin Ian King <colin.k...@canonical.com>
---
  drivers/clk/ti/adpll.c | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/clk/ti/adpll.c b/drivers/clk/ti/adpll.c
index 255cafb18336..bd7cb9a413c9 100644
--- a/drivers/clk/ti/adpll.c
+++ b/drivers/clk/ti/adpll.c
@@ -222,7 +222,7 @@ static int ti_adpll_setup_clock(struct ti_adpll_data *d, 
struct clk *clock,

/* Separate con_id in format "pll040dcoclkldo" to fit MAX_CON_ID */

        postfix = strrchr(name, '.');
-       if (strlen(postfix) > 1) {
+       if (postfix && strlen(postfix) > 1) {
                if (strlen(postfix) > ADPLL_MAX_CON_ID)
                        dev_warn(d->dev, "clock %s con_id lookup may fail\n",
                                 name);

Looks fine to me.

Acked-by: Tero Kristo <t-kri...@ti.com>