Rich Felker
5059deb1a5
the code which loads locale files was already rejecting locale names containing slashes. however, LC_MESSAGES records a locale name even if libc does not have a matching locale file, so that gettext or application code can use the recorded locale name for message translations to languages that libc does not support. this recorded name was not being checked for slashes, meaning that such code could potentially be tricked into directory traversal. in addition, since the value of a locale category is sometimes used as a pathname component by callers, the improved code rejects any value beginning with a dot. this prevents traversal to the parent directory via "..", use of the top-level locale directory via ".", and also avoids "hidden" directories as a side effect. finally, overly long locale names are now rejected (treated as an unrecognized name and thus as an alias for C.UTF-8) rather than being truncated.
musl libc
musl, pronounced like the word "mussel", is an MIT-licensed
implementation of the standard C library targetting the Linux syscall
API, suitable for use in a wide range of deployment environments. musl
offers efficient static and dynamic linking support, lightweight code
and low runtime overhead, strong fail-safe guarantees under correct
usage, and correctness in the sense of standards conformance and
safety. musl is built on the principle that these goals are best
achieved through simple code that is easy to understand and maintain.
The 1.1 release series for musl features coverage for all interfaces
defined in ISO C99 and POSIX 2008 base, along with a number of
non-standardized interfaces for compatibility with Linux, BSD, and
glibc functionality.
For basic installation instructions, see the included INSTALL file.
Information on full musl-targeted compiler toolchains, system
bootstrapping, and Linux distributions built on musl can be found on
the project website:
http://www.musl-libc.org/