diff mbox series

[v2] clk: renesas: cpg-mssr: Fix use after free if cpg_mssr_common_init() failed

Message ID 1671806417-32623-1-git-send-email-khoroshilov@ispras.ru
State New
Headers
Series [v2] clk: renesas: cpg-mssr: Fix use after free if cpg_mssr_common_init() failed |

Commit Message

Alexey Khoroshilov Dec. 23, 2022, 2:40 p.m. UTC 
  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>
---
v2: Move cpg_mssr_priv assignment just before return 0; instead of
clearing it as Geert Uytterhoeven <geert@linux-m68k.org> suggested.
 drivers/clk/renesas/renesas-cpg-mssr.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Comments

Geert Uytterhoeven Jan. 11, 2023, 3:34 p.m. UTC | #1 
On Fri, Dec 23, 2022 at 3:40 PM Alexey Khoroshilov
<khoroshilov@ispras.ru> wrote:
> 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>
> ---
> v2: Move cpg_mssr_priv assignment just before return 0; instead of
> clearing it as Geert Uytterhoeven <geert@linux-m68k.org> suggested.

Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
i.e. will queue in renesas-clk-for-v6.3.

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds
diff mbox series

Patch

diff --git a/drivers/clk/renesas/renesas-cpg-mssr.c b/drivers/clk/renesas/renesas-cpg-mssr.c
index 1a0cdf001b2f..5dce9779324d 100644
--- 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: