916ee6deae
[ Upstream commit bcac8bff90a6ee1629f90669cdb9d28fb86049b0 ]
Switch order of operations to avoid creating a short XDR buffer:
e.g., buflen = 12, old xdrlen = 12, new xdrlen = 20.
Having a short XDR buffer leads to lxa_maxcount be a few bytes
less than what is needed to retrieve the whole list when using
a buflen as returned by a call with size = 0:
buflen = listxattr(path, NULL, 0);
buf = malloc(buflen);
buflen = listxattr(path, buf, buflen);
For a file with one attribute (name = '123456'), the first call
with size = 0 will return buflen = 12 ('user.123456\x00').
The second call with size = 12, sends LISTXATTRS with
lxa_maxcount = 12 + 8 (cookie) + 4 (array count) = 24. The
XDR buffer needs 8 (cookie) + 4 (array count) + 4 (name count)
+ 6 (name len) + 2 (padding) + 4 (eof) = 28 which is 4 bytes
shorter than the lxa_maxcount provided in the call.
Fixes:
|
||
|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| io_uring | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
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 Restructured Text 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.