[PATCH] clk: samsung: exynos5410: fix refcount leak

[PATCH] clk: samsung: exynos5410: fix refcount leak

[Alexander A. Klimov]

Every value returned from of_clk_get() is supposed to be cleaned up
via clk_put() once not needed anymore.

Fixes: be95d2c7d918 ("clk: samsung: Add support for EPLL on exynos5410")
Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
---
 drivers/clk/samsung/clk-exynos5410.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/samsung/clk-exynos5410.c b/drivers/clk/samsung/clk-exynos5410.c
index baa9988c7bb7..0cd9b0392cf5 100644
--- a/drivers/clk/samsung/clk-exynos5410.c
+++ b/drivers/clk/samsung/clk-exynos5410.c
@@ -269,8 +269,12 @@ static void __init exynos5410_clk_init(struct device_node *np)
 {
 	struct clk *xxti = of_clk_get(np, 0);
 
-	if (!IS_ERR(xxti) && clk_get_rate(xxti) == 24 * MHZ)
-		exynos5410_plls[epll].rate_table = exynos5410_pll2550x_24mhz_tbl;
+	if (!IS_ERR(xxti)) {
+		if (clk_get_rate(xxti) == 24 * MHZ)
+			exynos5410_plls[epll].rate_table =
+				exynos5410_pll2550x_24mhz_tbl;
+		clk_put(xxti);
+	}
 
 	samsung_cmu_register_one(np, &cmu);
 
-- 
2.54.0

[PATCH] clk: tegra: tegra124-emc: fix krealloc() memory leak

[Alexander A. Klimov]

Don't just overwrite the original pointer passed to krealloc()
with its return value without checking latter:

    MEM = krealloc(MEM, SZ, GFP);

If krealloc() returns NULL, that erases the pointer
to the still allocated memory, hence leaks this memory.
Instead, use a temporary variable, check it's not NULL
and only then assign it to the original pointer:

    TMP = krealloc(MEM, SZ, GFP);
    if (!TMP) return;
    MEM = TMP;

Fixes: 888ca40e2843 ("clk: tegra: emc: Support multiple RAM codes")
Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
---
 drivers/clk/tegra/clk-tegra124-emc.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/drivers/clk/tegra/clk-tegra124-emc.c b/drivers/clk/tegra/clk-tegra124-emc.c
index f3b2c96fdcfc..8053fbbb06c8 100644
--- a/drivers/clk/tegra/clk-tegra124-emc.c
+++ b/drivers/clk/tegra/clk-tegra124-emc.c
@@ -446,14 +446,13 @@ static int load_timings_from_dt(struct tegra_clk_emc *tegra,
 	struct emc_timing *timings_ptr;
 	int child_count = of_get_child_count(node);
 	int i = 0, err;
-	size_t size;
+	size_t size = (tegra->num_timings + child_count) * sizeof(struct emc_timing);
+	void *mem = krealloc(tegra->timings, size, GFP_KERNEL);
 
-	size = (tegra->num_timings + child_count) * sizeof(struct emc_timing);
-
-	tegra->timings = krealloc(tegra->timings, size, GFP_KERNEL);
-	if (!tegra->timings)
+	if (!mem)
 		return -ENOMEM;
 
+	tegra->timings = mem;
 	timings_ptr = tegra->timings + tegra->num_timings;
 	tegra->num_timings += child_count;
 
-- 
2.54.0

Re: [PATCH] clk: samsung: exynos5410: fix refcount leak

[Brian Masney]

On Tue, May 26, 2026 at 08:13:12AM +0200, Alexander A. Klimov wrote:
> Every value returned from of_clk_get() is supposed to be cleaned up
> via clk_put() once not needed anymore.
> 
> Fixes: be95d2c7d918 ("clk: samsung: Add support for EPLL on exynos5410")
> Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>

Reviewed-by: Brian Masney <bmasney@redhat.com>

Re: [PATCH] clk: tegra: tegra124-emc: fix krealloc() memory leak

[Brian Masney]

On Tue, May 26, 2026 at 08:13:13AM +0200, Alexander A. Klimov wrote:
> Don't just overwrite the original pointer passed to krealloc()
> with its return value without checking latter:
> 
>     MEM = krealloc(MEM, SZ, GFP);
> 
> If krealloc() returns NULL, that erases the pointer
> to the still allocated memory, hence leaks this memory.
> Instead, use a temporary variable, check it's not NULL
> and only then assign it to the original pointer:
> 
>     TMP = krealloc(MEM, SZ, GFP);
>     if (!TMP) return;
>     MEM = TMP;
> 
> Fixes: 888ca40e2843 ("clk: tegra: emc: Support multiple RAM codes")
> Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>

Reviewed-by: Brian Masney <bmasney@redhat.com>

Re: [PATCH] clk: samsung: exynos5410: fix refcount leak

[Alexey Klimov]

On Tue May 26, 2026 at 7:13 AM BST, Alexander A. Klimov wrote:
> Every value returned from of_clk_get() is supposed to be cleaned up
> via clk_put() once not needed anymore.
>
> Fixes: be95d2c7d918 ("clk: samsung: Add support for EPLL on exynos5410")
> Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>

Reviewed-by: Alexey Klimov <alexey.klimov@linaro.org>

> ---
>  drivers/clk/samsung/clk-exynos5410.c | 8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/clk/samsung/clk-exynos5410.c b/drivers/clk/samsung/clk-exynos5410.c
> index baa9988c7bb7..0cd9b0392cf5 100644
> --- a/drivers/clk/samsung/clk-exynos5410.c
> +++ b/drivers/clk/samsung/clk-exynos5410.c
> @@ -269,8 +269,12 @@ static void __init exynos5410_clk_init(struct device_node *np)
>  {
>  	struct clk *xxti = of_clk_get(np, 0);
>  
> -	if (!IS_ERR(xxti) && clk_get_rate(xxti) == 24 * MHZ)
> -		exynos5410_plls[epll].rate_table = exynos5410_pll2550x_24mhz_tbl;
> +	if (!IS_ERR(xxti)) {
> +		if (clk_get_rate(xxti) == 24 * MHZ)
> +			exynos5410_plls[epll].rate_table =
> +				exynos5410_pll2550x_24mhz_tbl;
> +		clk_put(xxti);
> +	}
>  
>  	samsung_cmu_register_one(np, &cmu);

Best regards,
Alexey Klimov

Re: [PATCH] clk: samsung: exynos5410: fix refcount leak

[Peter Griffin]

On Tue, 26 May 2026 at 07:13, Alexander A. Klimov
<grandmaster@al2klimov.de> wrote:
>
> Every value returned from of_clk_get() is supposed to be cleaned up
> via clk_put() once not needed anymore.
>
> Fixes: be95d2c7d918 ("clk: samsung: Add support for EPLL on exynos5410")
> Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
> ---

Reviewed-by: Peter Griffin <peter.griffin@linaro.org>

>  drivers/clk/samsung/clk-exynos5410.c | 8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/clk/samsung/clk-exynos5410.c b/drivers/clk/samsung/clk-exynos5410.c
> index baa9988c7bb7..0cd9b0392cf5 100644
> --- a/drivers/clk/samsung/clk-exynos5410.c
> +++ b/drivers/clk/samsung/clk-exynos5410.c
> @@ -269,8 +269,12 @@ static void __init exynos5410_clk_init(struct device_node *np)
>  {
>         struct clk *xxti = of_clk_get(np, 0);
>
> -       if (!IS_ERR(xxti) && clk_get_rate(xxti) == 24 * MHZ)
> -               exynos5410_plls[epll].rate_table = exynos5410_pll2550x_24mhz_tbl;
> +       if (!IS_ERR(xxti)) {
> +               if (clk_get_rate(xxti) == 24 * MHZ)
> +                       exynos5410_plls[epll].rate_table =
> +                               exynos5410_pll2550x_24mhz_tbl;
> +               clk_put(xxti);
> +       }
>
>         samsung_cmu_register_one(np, &cmu);
>
> --
> 2.54.0
>
>

Re: [PATCH] clk: tegra: tegra124-emc: fix krealloc() memory leak

[Thierry Reding]

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On Tue, May 26, 2026 at 08:13:13AM +0200, Alexander A. Klimov wrote:
> Don't just overwrite the original pointer passed to krealloc()
> with its return value without checking latter:
> 
>     MEM = krealloc(MEM, SZ, GFP);
> 
> If krealloc() returns NULL, that erases the pointer
> to the still allocated memory, hence leaks this memory.
> Instead, use a temporary variable, check it's not NULL
> and only then assign it to the original pointer:
> 
>     TMP = krealloc(MEM, SZ, GFP);
>     if (!TMP) return;
>     MEM = TMP;
> 
> Fixes: 888ca40e2843 ("clk: tegra: emc: Support multiple RAM codes")
> Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
> ---
>  drivers/clk/tegra/clk-tegra124-emc.c | 9 ++++-----
>  1 file changed, 4 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/clk/tegra/clk-tegra124-emc.c b/drivers/clk/tegra/clk-tegra124-emc.c
> index f3b2c96fdcfc..8053fbbb06c8 100644
> --- a/drivers/clk/tegra/clk-tegra124-emc.c
> +++ b/drivers/clk/tegra/clk-tegra124-emc.c
> @@ -446,14 +446,13 @@ static int load_timings_from_dt(struct tegra_clk_emc *tegra,
>  	struct emc_timing *timings_ptr;
>  	int child_count = of_get_child_count(node);
>  	int i = 0, err;
> -	size_t size;
> +	size_t size = (tegra->num_timings + child_count) * sizeof(struct emc_timing);
> +	void *mem = krealloc(tegra->timings, size, GFP_KERNEL);
>  
> -	size = (tegra->num_timings + child_count) * sizeof(struct emc_timing);

This looks really wild now. I think it'd be better to follow the
original style:

	size_t size;
	void *mem;

	size = ...;

	mem = krealloc(...);
	if (!mem)
		...

With that:

Acked-by: Thierry Reding <treding@nvidia.com>

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Re: [PATCH] clk: samsung: exynos5410: fix refcount leak

[Krzysztof Kozlowski]

On 26/05/2026 08:13, Alexander A. Klimov wrote:
> Every value returned from of_clk_get() is supposed to be cleaned up
> via clk_put() once not needed anymore.
> 
> Fixes: be95d2c7d918 ("clk: samsung: Add support for EPLL on exynos5410")
> Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>


Does not apply - you messed somehow sending these.

Grabbing thread from
lore.kernel.org/all/20260526061321.6123-1-grandmaster@al2klimov.de/t.mbox.gz
Checking for newer revisions
Grabbing search results from lore.kernel.org
Analyzing 13 messages in the thread
WARNING: duplicate messages found at index 1
   Subject 1: dmaengine: ioatdma: use !kstrtoint(), not sscanf()!=-1
   Subject 2: tlclk: if sscanf() fails, fall back to 0, not random value
  2 is not a reply... assume additional patch
WARNING: duplicate messages found at index 1
   Subject 1: clk: samsung: exynos5410: fix refcount leak
   Subject 2: dmaengine: ioatdma: use !kstrtoint(), not sscanf()!=-1
  2 is not a reply... assume additional patch
Assuming new revision: v2 ([PATCH] clk: tegra: tegra124-emc: fix
krealloc() memory leak)


Best regards,
Krzysztof

Re: [PATCH] clk: samsung: exynos5410: fix refcount leak

[Alexander A. Klimov]

On 5/30/26 18:26, Krzysztof Kozlowski wrote:
> On 26/05/2026 08:13, Alexander A. Klimov wrote:
>> Every value returned from of_clk_get() is supposed to be cleaned up
>> via clk_put() once not needed anymore.
>>
>> Fixes: be95d2c7d918 ("clk: samsung: Add support for EPLL on exynos5410")
>> Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
> 
> 
> Does not apply - you messed somehow sending these.

Strange... copy&paste from
https://lore.kernel.org/all/20260526061321.6123-1-grandmaster@al2klimov.de/
(From: ... 2.54.0) applies to Linus' master.

Wait... ! Don't say because I fired all my compiled patches
at once via git-send-email(1), they assembled to one thread?
🙈

[PATCH v2] clk: tegra: tegra124-emc: fix krealloc() memory leak

[Alexander A. Klimov]

Don't just overwrite the original pointer passed to krealloc()
with its return value without checking latter:

    MEM = krealloc(MEM, SZ, GFP);

If krealloc() returns NULL, that erases the pointer
to the still allocated memory, hence leaks this memory.
Instead, use a temporary variable, check it's not NULL
and only then assign it to the original pointer:

    TMP = krealloc(MEM, SZ, GFP);
    if (!TMP) return;
    MEM = TMP;

Fixes: 888ca40e2843 ("clk: tegra: emc: Support multiple RAM codes")
Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
---
 v2: Separate variable declaration/init
 v2: While on it, enhance variable name
 v2: While on it, explicit variable type
 v2: While on it, re-order variables (reverse Xmas tree)

 [✓] scripts/checkpatch.pl --strict
 [✓] allmodconfig compiled (i686, LLVM)
 [✓] localyesconfig booted (IBM T43)

 Note to myself: use --in-reply-to=ahilgKKwkttOd9H6@orome

 drivers/clk/tegra/clk-tegra124-emc.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/tegra/clk-tegra124-emc.c b/drivers/clk/tegra/clk-tegra124-emc.c
index f3b2c96fdcfc..81e4c02a807c 100644
--- a/drivers/clk/tegra/clk-tegra124-emc.c
+++ b/drivers/clk/tegra/clk-tegra124-emc.c
@@ -445,15 +445,17 @@ static int load_timings_from_dt(struct tegra_clk_emc *tegra,
 {
 	struct emc_timing *timings_ptr;
 	int child_count = of_get_child_count(node);
+	struct emc_timing *timings;
 	int i = 0, err;
 	size_t size;
 
 	size = (tegra->num_timings + child_count) * sizeof(struct emc_timing);
 
-	tegra->timings = krealloc(tegra->timings, size, GFP_KERNEL);
-	if (!tegra->timings)
+	timings = krealloc(tegra->timings, size, GFP_KERNEL);
+	if (!timings)
 		return -ENOMEM;
 
+	tegra->timings = timings;
 	timings_ptr = tegra->timings + tegra->num_timings;
 	tegra->num_timings += child_count;
 
-- 
2.54.0

Re: [PATCH v2] clk: tegra: tegra124-emc: fix krealloc() memory leak

[Thierry Reding]

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On Sun, May 31, 2026 at 09:52:52PM +0200, Alexander A. Klimov wrote:
> Don't just overwrite the original pointer passed to krealloc()
> with its return value without checking latter:
> 
>     MEM = krealloc(MEM, SZ, GFP);
> 
> If krealloc() returns NULL, that erases the pointer
> to the still allocated memory, hence leaks this memory.
> Instead, use a temporary variable, check it's not NULL
> and only then assign it to the original pointer:
> 
>     TMP = krealloc(MEM, SZ, GFP);
>     if (!TMP) return;
>     MEM = TMP;
> 
> Fixes: 888ca40e2843 ("clk: tegra: emc: Support multiple RAM codes")
> Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
> ---
>  v2: Separate variable declaration/init
>  v2: While on it, enhance variable name
>  v2: While on it, explicit variable type
>  v2: While on it, re-order variables (reverse Xmas tree)
> 
>  [✓] scripts/checkpatch.pl --strict
>  [✓] allmodconfig compiled (i686, LLVM)
>  [✓] localyesconfig booted (IBM T43)

The latter two are a bit pointless because they are not going to hit
this because the driver depends on ARCH_TEGRA which doesn't exist on
i686 allmodconfig and booting this on a T43 isn't going to hit this
either.

>  Note to myself: use --in-reply-to=ahilgKKwkttOd9H6@orome

It's not generally useful to send as replies to earlier versions. Just
regular sending is good enough. We have tools to track versions and
such.

> 
>  drivers/clk/tegra/clk-tegra124-emc.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/clk/tegra/clk-tegra124-emc.c b/drivers/clk/tegra/clk-tegra124-emc.c
> index f3b2c96fdcfc..81e4c02a807c 100644
> --- a/drivers/clk/tegra/clk-tegra124-emc.c
> +++ b/drivers/clk/tegra/clk-tegra124-emc.c
> @@ -445,15 +445,17 @@ static int load_timings_from_dt(struct tegra_clk_emc *tegra,
>  {
>  	struct emc_timing *timings_ptr;
>  	int child_count = of_get_child_count(node);
> +	struct emc_timing *timings;

I guess we could've reused timings_ptr. Or remove timings_ptr and use
the new one, but I guess this is fine, too:

Reviewed-by: Thierry Reding <treding@nvidia.com>

>  	int i = 0, err;
>  	size_t size;
>  
>  	size = (tegra->num_timings + child_count) * sizeof(struct emc_timing);
>  
> -	tegra->timings = krealloc(tegra->timings, size, GFP_KERNEL);
> -	if (!tegra->timings)
> +	timings = krealloc(tegra->timings, size, GFP_KERNEL);
> +	if (!timings)
>  		return -ENOMEM;
>  
> +	tegra->timings = timings;
>  	timings_ptr = tegra->timings + tegra->num_timings;
>  	tegra->num_timings += child_count;

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