Justin Stitt
9dd12ed95c
strncpy() is deprecated for use on NUL-terminated destination strings
[1] and as such we should prefer more robust and less ambiguous string
interfaces.
We know that info-device should be NUL-terminated based on its use with
strlen():
| static int __init mtdpstore_init(void)
| {
| int ret;
| struct mtdpstore_context *cxt = &oops_cxt;
| struct pstore_blk_config *info = &cxt->info;
|
| ret = pstore_blk_get_config(info);
| if (unlikely(ret))
| return ret;
|
| if (strlen(info->device) == 0) {
| pr_err("mtd device must be supplied (device name is empty)\n");
...
Considering the above, a suitable replacement is `strscpy` [2] due to
the fact that it guarantees NUL-termination on the destination buffer.
Note that this patch relies on the _new_ 2-argument version of strscpy()
introduced in Commit e6584c3964 ("string: Allow 2-argument strscpy()").
Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
Link: https://github.com/KSPP/linux/issues/90
Cc: <linux-hardening@vger.kernel.org>
Signed-off-by: Justin Stitt <justinstitt@google.com>
Link: https://lore.kernel.org/r/20240328-strncpy-fs-pstore-blk-c-v1-1-5748cdc22a53@google.com
Signed-off-by: Kees Cook <keescook@chromium.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
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In order to build the documentation, use ``make htmldocs`` or
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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.