GCC 14 introduces a new -Walloc-size included in -Wextra which gives:
```
libpkgconf/personality.c:260:11: warning: allocation of insufficient size '1' for type 'pkgconf_cross_personality_t' {aka 'struct pkgconf_cross_personality_'} with size '48' [-Walloc-size]
libpkgconf/queue.c:46:33: warning: allocation of insufficient size '1' for type 'pkgconf_queue_t' {aka'struct pkgconf_queue_'} with size '16' [-Walloc-size]
libpkgconf/client.c:164:33: warning: allocation of insufficient size '1' for type 'pkgconf_client_t' {aka 'struct pkgconf_client_'} with size '120' [-Walloc-size]
libpkgconf/path.c:105:14: warning: allocation of insufficient size '1' for type 'pkgconf_path_t' {aka 'struct pkgconf_path_'} with size '24' [-Walloc-size]
libpkgconf/path.c:237:22: warning: allocation of insufficient size '1' for type 'pkgconf_path_t' {aka 'struct pkgconf_path_'} with size '24' [-Walloc-size]
libpkgconf/tuple.c:239:34: warning: allocation of insufficient size '1' for type 'pkgconf_tuple_t' {aka 'struct pkgconf_tuple_'} with size '24' [-Walloc-size]
libpkgconf/dependency.c:133:13: warning: allocation of insufficient size '1' for type 'pkgconf_dependency_t' {aka 'struct pkgconf_dependency_'} with size '44' [-Walloc-size]
libpkgconf/dependency.c:472:17: warning: allocation of insufficient size '1' for type 'pkgconf_dependency_t' {aka 'struct pkgconf_dependency_'} with size '44' [-Walloc-size]
libpkgconf/fragment.c:146:22: warning: allocation of insufficient size '1' for type 'pkgconf_fragment_t' {aka 'struct pkgconf_fragment_'} with size '24' [-Walloc-size]
libpkgconf/fragment.c:195:22: warning: allocation of insufficient size '1' for type 'pkgconf_fragment_t' {aka 'struct pkgconf_fragment_'} with size '24' [-Walloc-size]
libpkgconf/fragment.c:356:14: warning: allocation of insufficient size '1' for type 'pkgconf_fragment_t' {aka 'struct pkgconf_fragment_'} with size '24' [-Walloc-size]
libpkgconf/pkg.c:422:13: warning: allocation of insufficient size '1' for type 'pkgconf_pkg_t' {aka 'struct pkgconf_pkg_'} with size '188' [-Walloc-size]
libpkgconf/client.c:164:33: warning: allocation of insufficient size '1' for type 'pkgconf_client_t' {aka 'struct pkgconf_client_'} with size '224' [-Walloc-size]
libpkgconf/personality.c:260:11: warning: allocation of insufficient size '1' for type 'pkgconf_cross_personality_t' {aka 'struct pkgconf_cross_personality_'} with size '96' [-Walloc-size]
libpkgconf/dependency.c:133:13: warning: allocation of insufficient size '1' for type 'pkgconf_dependency_t' {aka 'struct pkgconf_dependency_'} with size '80' [-Walloc-size]
libpkgconf/dependency.c:472:17: warning: allocation of insufficient size '1' for type 'pkgconf_dependency_t' {aka 'struct pkgconf_dependency_'} with size '80' [-Walloc-size]
libpkgconf/path.c:105:14: warning: allocation of insufficient size '1' for type 'pkgconf_path_t' {aka 'struct pkgconf_path_'} with size '48' [-Walloc-size]
libpkgconf/path.c:237:22: warning: allocation of insufficient size '1' for type 'pkgconf_path_t' {aka 'struct pkgconf_path_'} with size '48' [-Walloc-size]
libpkgconf/queue.c:46:33: warning: allocation of insufficient size '1' for type 'pkgconf_queue_t' {aka 'struct pkgconf_queue_'} with size '32' [-Walloc-size]
libpkgconf/tuple.c:239:34: warning: allocation of insufficient size '1' for type 'pkgconf_tuple_t' {aka 'struct pkgconf_tuple_'} with size '48' [-Walloc-size]
libpkgconf/fragment.c:146:22: warning: allocation of insufficient size '1' for type 'pkgconf_fragment_t' {aka 'struct pkgconf_fragment_'} with size '48' [-Walloc-size]
libpkgconf/fragment.c:195:22: warning: allocation of insufficient size '1' for type 'pkgconf_fragment_t' {aka 'struct pkgconf_fragment_'} with size '48' [-Walloc-size]
libpkgconf/fragment.c:356:14: warning: allocation of insufficient size '1' for type 'pkgconf_fragment_t' {aka 'struct pkgconf_fragment_'} with size '48' [-Walloc-size]
libpkgconf/pkg.c:422:13: warning: allocation of insufficient size '1' for type 'pkgconf_pkg_t' {aka 'struct pkgconf_pkg_'} with size '360' [-Walloc-size]
```
The calloc prototype is:
```
void *calloc(size_t nmemb, size_t size);
```
So, just swap the number of members and size arguments to match the prototype, as
we're initialising 1 struct of size `sizeof(struct ...)`. GCC then sees we're not
doing anything wrong.
The only exception there is for argv which I fixed while at it.
Signed-off-by: Sam James <sam@gentoo.org>
otherwise a buffer overflow occurs.
this has been a bug in pkgconf since the beginning, it seems.
instead of disclosing the bug correctly, a "hotshot" developer
decided to blog about it instead. sigh.
https://nullprogram.com/blog/2023/01/18/
ci/woodpecker/push/woodpecker Pipeline was successfulDetails
This is required to make the pointer safely re-usable after being freed,
otherwise the list still says that it has nodes, but they point nowhere.
This is particularly important for libpkgconf, if a caller needs to
re-enter the library after freeing a path in a static path (such as the
default personality)
This is the same issue which has been fixed in dependency code.
If a line contains a variable which is longer than PKGCONF_ITEM_SIZE,
then the varname buffer overflows.
The code itself still does not check if a closing } exists and
truncates variable names which are too long. Since these would
be functional changes and this commit is about a protection against
undefined behaviour on a language level, these changes are not
included.
Proof of concept:
$ echo "Description: poc" > poc.pc
$ echo "Version: 1" >> poc.pc
$ echo -n 'Name: ${'
$ dd if=/dev/zero bs=1 count=66535 | tr '\0' 'x' >> poc.pc
$ echo >> poc.pc
$ pkgconf poc.pc
On my Linux system, when compiled with gcc, the varname buffer overflows
directly into buf, which means that no crash can be notified.
It's easiest to figure out when adding strlen() and sizeof() output
as debug lines.
If a key is defined with no value, dequote will allocate a buffer with a
length of 0. Since the buffer's length is 0, any manipulation of its
content is UB.
Example .pc file:
prefix=/usr
exec_prefix=${prefix}
libdir=${exec_prefix}/lib
includedir=${prefix}/include
xcflags=
xlibs= -lSM -lICE -lX11
Name: Obt
Description: Openbox Toolkit Library
Version: 3.6
Requires: glib-2.0 libxml-2.0
Libs: -L${libdir} -lobt ${xlibs}
Cflags: -I${includedir}/openbox/3.6 ${xcflags}
Output using pkgconf 1.5.2 on x86_64 Linux/musl:
% pkgconf --cflags obt-3.5
-I/usr/include/openbox/3.6 \�\\�I\�\ -I/usr/include/glib-2.0 -I/usr/lib/glib-2.0/include -I/usr/include/libxml2
This allows compatibility between legacy pkg-config's broken sysroot implementation and pkgconf's sysroot
implementation, by removing any prepended sysroot paths and preferencing the variable expansion sysroot path
we typically do instead.
Closes github #123.