When the best clk is searched, we iterate over all possible clk.

If we find a better match, the previous one, if any, needs to be freed. If a better match has already been found, we still need to free the new one, otherwise it leaks.

Cc: stable@vger.kernel.org # v3.3+ Reviewed-by: Krzysztof Kozlowski krzysztof.kozlowski@linaro.org Reviewed-by: Andi Shyti andi.shyti@kernel.org Fixes: 5f5a7a5578c5 ("serial: samsung: switch to clkdev based clock lookup") Signed-off-by: Christophe JAILLET christophe.jaillet@wanadoo.fr --- I think that some clk_put() are also missing somewhere else in the driver but won't be able to investigate further.

v2: No code change Add Cc: stable [Andi Shyti, as suggested for patch 1/2] Add R-b tags

v1: https://lore.kernel.org/all/93bf8f574310256fcea50e5c5a62b5c37e20bb14.1686285... --- drivers/tty/serial/samsung_tty.c | 8 ++++++++ 1 file changed, 8 insertions(+)

diff --git a/drivers/tty/serial/samsung_tty.c b/drivers/tty/serial/samsung_tty.c index a92a23e1964e..0b37019820b4 100644 --- a/drivers/tty/serial/samsung_tty.c +++ b/drivers/tty/serial/samsung_tty.c @@ -1490,10 +1490,18 @@ static unsigned int s3c24xx_serial_getclk(struct s3c24xx_uart_port *ourport, calc_deviation = -calc_deviation;

if (calc_deviation < deviation) { + /* + * If we find a better clk, release the previous one, if + * any. + */ + if (!IS_ERR(*best_clk)) + clk_put(*best_clk); *best_clk = clk; best_quot = quot; *clk_num = cnt; deviation = calc_deviation; + } else { + clk_put(clk); } }

This is a note to let you know that I've just added the patch titled

tty: serial: samsung_tty: Fix a memory leak in

to my tty git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty.git in the tty-next branch.

The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.)

The patch will also be merged in the next major kernel release during the merge window.

If you have any questions about this process, please let me know.

From a9c09546e903f1068acfa38e1ee18bded7114b37 Mon Sep 17 00:00:00 2001 From: Christophe JAILLET christophe.jaillet@wanadoo.fr Date: Sat, 10 Jun 2023 17:59:25 +0200 Subject: tty: serial: samsung_tty: Fix a memory leak in s3c24xx_serial_getclk() in case of error

If clk_get_rate() fails, the clk that has just been allocated needs to be freed.

Cc: stable@vger.kernel.org # v3.3+ Reviewed-by: Krzysztof Kozlowski krzysztof.kozlowski@linaro.org Reviewed-by: Andi Shyti andi.shyti@kernel.org Fixes: 5f5a7a5578c5 ("serial: samsung: switch to clkdev based clock lookup") Signed-off-by: Christophe JAILLET christophe.jaillet@wanadoo.fr Reviewed-by: Jiri Slaby jirislaby@kernel.org Message-ID: e4baf6039368f52e5a5453982ddcb9a330fc689e.1686412569.git.christophe.jaillet@wanadoo.fr Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/tty/serial/samsung_tty.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/tty/serial/samsung_tty.c b/drivers/tty/serial/samsung_tty.c index 2a7520ad3abd..a92a23e1964e 100644 --- a/drivers/tty/serial/samsung_tty.c +++ b/drivers/tty/serial/samsung_tty.c @@ -1459,8 +1459,12 @@ static unsigned int s3c24xx_serial_getclk(struct s3c24xx_uart_port *ourport, continue;

rate = clk_get_rate(clk); - if (!rate) + if (!rate) { + dev_err(ourport->port.dev, + "Failed to get clock rate for %s.\n", clkname); + clk_put(clk); continue; + }

if (ourport->info->has_divslot) { unsigned long div = rate / req_baud;