This is a note to let you know that I've just added the patch titled rtc: pcf2127: fix bug when reading alarm registers to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: rtc-pcf2127-fix-bug-when-reading-alarm-registers.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit f5bf43f041f9356412aacdad9350c3470f7c2861 Author: Hugo Villeneuve <hvilleneuve@xxxxxxxxxxxx> Date: Tue Feb 8 11:29:07 2022 -0500 rtc: pcf2127: fix bug when reading alarm registers [ Upstream commit 73ce05302007eece23a6acb7dc124c92a2209087 ] The first bug is that reading the 5 alarm registers results in a read operation of 20 bytes. The reason is because the destination buffer is defined as an array of "unsigned int", and we use the sizeof() operator on this array to define the bulk read count. The second bug is that the read value is invalid, because we are indexing the destination buffer as integers (4 bytes), instead of indexing it as u8. Changing the destination buffer type to u8 fixes both problems. Signed-off-by: Hugo Villeneuve <hvilleneuve@xxxxxxxxxxxx> Signed-off-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx> Link: https://lore.kernel.org/r/20220208162908.3182581-1-hugo@xxxxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/rtc/rtc-pcf2127.c b/drivers/rtc/rtc-pcf2127.c index 56c58b055dff..43f801107095 100644 --- a/drivers/rtc/rtc-pcf2127.c +++ b/drivers/rtc/rtc-pcf2127.c @@ -374,7 +374,8 @@ static int pcf2127_watchdog_init(struct device *dev, struct pcf2127 *pcf2127) static int pcf2127_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) { struct pcf2127 *pcf2127 = dev_get_drvdata(dev); - unsigned int buf[5], ctrl2; + u8 buf[5]; + unsigned int ctrl2; int ret; ret = regmap_read(pcf2127->regmap, PCF2127_REG_CTRL2, &ctrl2);