Julien Stephan
dc537a72f6
[ Upstream commit c4ec8dedca ]
Some callbacks from iio_info structure are accessed without any check, so
if a driver doesn't implement them trying to access the corresponding
sysfs entries produce a kernel oops such as:
[ 2203.527791] Unable to handle kernel NULL pointer dereference at virtual address 00000000 when execute
[...]
[ 2203.783416] Call trace:
[ 2203.783429] iio_read_channel_info_avail from dev_attr_show+0x18/0x48
[ 2203.789807] dev_attr_show from sysfs_kf_seq_show+0x90/0x120
[ 2203.794181] sysfs_kf_seq_show from seq_read_iter+0xd0/0x4e4
[ 2203.798555] seq_read_iter from vfs_read+0x238/0x2a0
[ 2203.802236] vfs_read from ksys_read+0xa4/0xd4
[ 2203.805385] ksys_read from ret_fast_syscall+0x0/0x54
[ 2203.809135] Exception stack(0xe0badfa8 to 0xe0badff0)
[ 2203.812880] dfa0: 00000003 b6f10f80 00000003 b6eab000 00020000 00000000
[ 2203.819746] dfc0: 00000003 b6f10f80 7ff00000 00000003 00000003 00000000 00020000 00000000
[ 2203.826619] dfe0: b6e1bc88 bed80958 b6e1bc94 b6e1bcb0
[ 2203.830363] Code: bad PC value
[ 2203.832695] ---[ end trace 0000000000000000 ]---
Reviewed-by: Nuno Sa <nuno.sa@analog.com>
Signed-off-by: Julien Stephan <jstephan@baylibre.com>
Link: https://lore.kernel.org/r/20240530-iio-core-fix-segfault-v3-1-8b7cd2a03773@baylibre.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.