diff options
| author | Matteo Martelli <matteomartelli3@gmail.com> | 2024-12-02 18:11:07 +0300 |
|---|---|---|
| committer | Jonathan Cameron <Jonathan.Cameron@huawei.com> | 2024-12-11 22:20:49 +0300 |
| commit | 22ccb0a1c57c436de899ccd3170d6d2ce7238836 (patch) | |
| tree | 8fd87290d2ec5b82c9866d69147aa6519589195a /include/linux | |
| parent | ca56951352ca26a15e9a62a7e682e56f1c01bf53 (diff) | |
| download | linux-22ccb0a1c57c436de899ccd3170d6d2ce7238836.tar.xz | |
iio: consumers: ensure read buffers for labels and ext_info are page aligned
Attributes of iio providers are exposed via sysfs. Typically, providers
pass attribute values to the iio core, which handles formatting and
printing to sysfs. However, some attributes, such as labels or extended
info, are directly formatted and printed to sysfs by provider drivers
using sysfs_emit() and sysfs_emit_at(). These helpers assume the read
buffer, allocated by sysfs fop, is page-aligned. When these attributes
are accessed by consumer drivers, the read buffer is allocated by the
consumer and may not be page-aligned, leading to failures in the
provider's callback that utilizes sysfs_emit*.
Add a check to ensure that read buffers for labels and external info
attributes are page-aligned. Update the prototype documentation as well.
Signed-off-by: Matteo Martelli <matteomartelli3@gmail.com>
Link: https://patch.msgid.link/20241202-iio-kmalloc-align-v1-1-aa9568c03937@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/iio/consumer.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/include/linux/iio/consumer.h b/include/linux/iio/consumer.h index 333d1d8ccb37..6a4479616479 100644 --- a/include/linux/iio/consumer.h +++ b/include/linux/iio/consumer.h @@ -418,7 +418,7 @@ unsigned int iio_get_channel_ext_info_count(struct iio_channel *chan); * @chan: The channel being queried. * @attr: The ext_info attribute to read. * @buf: Where to store the attribute value. Assumed to hold - * at least PAGE_SIZE bytes. + * at least PAGE_SIZE bytes and to be aligned at PAGE_SIZE. * * Returns the number of bytes written to buf (perhaps w/o zero termination; * it need not even be a string), or an error code. @@ -445,7 +445,7 @@ ssize_t iio_write_channel_ext_info(struct iio_channel *chan, const char *attr, * iio_read_channel_label() - read label for a given channel * @chan: The channel being queried. * @buf: Where to store the attribute value. Assumed to hold - * at least PAGE_SIZE bytes. + * at least PAGE_SIZE bytes and to be aligned at PAGE_SIZE. * * Returns the number of bytes written to buf, or an error code. */ |