This is a note to let you know that I've just added the patch titled iio: buffer: Fix memory leak in __iio_buffer_alloc_sysfs_and_mask() to my char-misc git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git in the char-misc-testing 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 be merged to the char-misc-next branch sometime soon, after it passes testing, and the merge window is open. If you have any questions about this process, please let me know. >From 9a2ff8009e53296e47de72d5af0bc31cd53274ff Mon Sep 17 00:00:00 2001 From: Yang Yingliang <yangyingliang@xxxxxxxxxx> Date: Wed, 13 Oct 2021 17:43:43 +0800 Subject: iio: buffer: Fix memory leak in __iio_buffer_alloc_sysfs_and_mask() When iio_buffer_wrap_attr() returns NULL or buffer->buffer_group.name alloc fails, the 'attr' which is allocated in __iio_buffer_alloc_sysfs_and_mask() is not freed, and cause memory leak. unreferenced object 0xffff888014882a00 (size 64): comm "i2c-adjd_s311-8", pid 424, jiffies 4294907737 (age 44.396s) hex dump (first 32 bytes): 00 0f 8a 15 80 88 ff ff 00 0e 8a 15 80 88 ff ff ................ 80 04 8a 15 80 88 ff ff 80 05 8a 15 80 88 ff ff ................ backtrace: [<0000000021752e67>] __kmalloc+0x1af/0x3c0 [<0000000043e8305c>] iio_buffers_alloc_sysfs_and_mask+0xe73/0x1570 [industrialio] [<00000000b7aa5a17>] __iio_device_register+0x483/0x1a30 [industrialio] [<000000003fa0fb2f>] __devm_iio_device_register+0x23/0x90 [industrialio] [<000000003ab040cf>] adjd_s311_probe+0x19c/0x200 [adjd_s311] [<0000000080458969>] i2c_device_probe+0xa31/0xbe0 [<00000000e20678ad>] really_probe+0x299/0xc30 [<000000006bea9b27>] __driver_probe_device+0x357/0x500 [<00000000e1df10d4>] driver_probe_device+0x4e/0x140 [<0000000003661beb>] __device_attach_driver+0x257/0x340 [<000000005bb4aa26>] bus_for_each_drv+0x166/0x1e0 [<00000000272c5236>] __device_attach+0x272/0x420 [<00000000d52a96ae>] bus_probe_device+0x1eb/0x2a0 [<00000000129f7737>] device_add+0xbf0/0x1f90 [<000000005eed4e52>] i2c_new_client_device+0x622/0xb20 [<00000000b85a9c43>] new_device_store+0x1fa/0x420 This patch fix to free it before the error return. Reported-by: Hulk Robot <hulkci@xxxxxxxxxx> Fixes: 15097c7a1adc ("iio: buffer: wrap all buffer attributes into iio_dev_attr") Fixes: d9a625744ed0 ("iio: core: merge buffer/ & scan_elements/ attributes") Signed-off-by: Yang Yingliang <yangyingliang@xxxxxxxxxx> Link: https://lore.kernel.org/r/20211013094343.315275-1-yangyingliang@xxxxxxxxxx Cc: <Stable@xxxxxxxxxxxxxxx> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> --- drivers/iio/industrialio-buffer.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-buffer.c index 55802da1deee..e2587237dbf9 100644 --- a/drivers/iio/industrialio-buffer.c +++ b/drivers/iio/industrialio-buffer.c @@ -1536,6 +1536,7 @@ static int __iio_buffer_alloc_sysfs_and_mask(struct iio_buffer *buffer, sizeof(struct attribute *) * buffer_attrcount); buffer_attrcount += ARRAY_SIZE(iio_buffer_attrs); + buffer->buffer_group.attrs = attr; for (i = 0; i < buffer_attrcount; i++) { struct attribute *wrapped; @@ -1543,7 +1544,7 @@ static int __iio_buffer_alloc_sysfs_and_mask(struct iio_buffer *buffer, wrapped = iio_buffer_wrap_attr(buffer, attr[i]); if (!wrapped) { ret = -ENOMEM; - goto error_free_scan_mask; + goto error_free_buffer_attrs; } attr[i] = wrapped; } @@ -1558,8 +1559,6 @@ static int __iio_buffer_alloc_sysfs_and_mask(struct iio_buffer *buffer, goto error_free_buffer_attrs; } - buffer->buffer_group.attrs = attr; - ret = iio_device_register_sysfs_group(indio_dev, &buffer->buffer_group); if (ret) goto error_free_buffer_attr_group_name; -- 2.33.1