clk: renesas: cpg-mssr: Fix use after free if cpg_mssr_common_init() failed

If cpg_mssr_common_init() fails after assigning priv to global variable
cpg_mssr_priv, it deallocates priv, but cpg_mssr_priv keeps dangling
pointer that potentially can be used later.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: 1f7db7bbf031 ("clk: renesas: cpg-mssr: Add early clock support")
Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/1671806417-32623-1-git-send-email-khoroshilov@ispras.ru
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

diff --git a/drivers/clk/renesas/renesas-cpg-mssr.c b/drivers/clk/renesas/renesas-cpg-mssr.c
index 1a0cdf0..5dce977 100644 (file)
--- a/drivers/clk/renesas/renesas-cpg-mssr.c
+++ b/drivers/clk/renesas/renesas-cpg-mssr.c
@@ -989,7 +989,6 @@ static int __init cpg_mssr_common_init(struct device *dev,
                goto out_err;
        }
 
-       cpg_mssr_priv = priv;
        priv->num_core_clks = info->num_total_core_clks;
        priv->num_mod_clks = info->num_hw_mod_clks;
        priv->last_dt_core_clk = info->last_dt_core_clk;
@@ -1019,6 +1018,8 @@ static int __init cpg_mssr_common_init(struct device *dev,
        if (error)
                goto out_err;
 
+       cpg_mssr_priv = priv;
+
        return 0;
 
 out_err: