On Mon, May 03, 2021 at 12:01:43PM +0200, Tim Wiederhake wrote:
When other preloaded libraries wrap and / or make calls to `realpath` (e.g. LLVM's AddessSanitizer), the second parameter is no longer guaranteed to be NULL.
Signed-off-by: Tim Wiederhake <twiederh@redhat.com> --- build-aux/syntax-check.mk | 2 +- tests/virfilemock.c | 12 ++++++------ 2 files changed, 7 insertions(+), 7 deletions(-)
diff --git a/build-aux/syntax-check.mk b/build-aux/syntax-check.mk index 552d639119..03b7599abc 100644 --- a/build-aux/syntax-check.mk +++ b/build-aux/syntax-check.mk @@ -1740,7 +1740,7 @@ exclude_file_name_regexp--sc_libvirt_unmarked_diagnostics = \ exclude_file_name_regexp--sc_po_check = ^(docs/|src/rpc/gendispatch\.pl$$|tests/commandtest.c$$)
exclude_file_name_regexp--sc_prohibit_PATH_MAX = \ - ^build-aux/syntax-check\.mk$$ + ^(build-aux/syntax-check\.mk|tests/virfilemock.c)$$
exclude_file_name_regexp--sc_prohibit_access_xok = \ ^(src/util/virutil\.c)$$ diff --git a/tests/virfilemock.c b/tests/virfilemock.c index 7c9174bdd9..cba66feac0 100644 --- a/tests/virfilemock.c +++ b/tests/virfilemock.c @@ -24,7 +24,6 @@ #if WITH_LINUX_MAGIC_H # include <linux/magic.h> #endif -#include <assert.h>
#include "virmock.h" #include "virstring.h" @@ -186,15 +185,16 @@ realpath(const char *path, char *resolved)
if (getenv("LIBVIRT_MTAB")) { const char *p; - char *ret;
- assert(resolved == NULL); + if (!resolved) + resolved = g_new0(char, PATH_MAX); + if ((p = STRSKIP(path, "/some/symlink"))) - ret = g_strdup_printf("/gluster%s", p); + g_snprintf(resolved, PATH_MAX, "/gluster%s", p); else - ret = g_strdup(path); + g_strlcpy(resolved, path, PATH_MAX);
- return ret; + return resolved;
This seems way too complicated. It will be used only in tests where we know what paths we use. Also the manpage for realpath states the following: If resolved_path is specified as NULL, then realpath() uses malloc(3) to allocate a buffer of up to PATH_MAX bytes to hold the resolved pathname, and returns a pointer to this buffer. The caller should deallocate this buffer using free(3). where the important word part is "up to PATH_MAX". The code introduced by this patch always allocates PATH_MAX bytes. How about this which to me looks like a good enough solution for tests: if (getenv("LIBVIRT_MTAB")) { const char *p; if ((p = STRSKIP(path, "/some/symlink"))) resolved = g_strdup_printf("/gluster%s", p); else resolved = g_strdup(path); return resolved; } Pavel
}
return real_realpath(path, resolved); -- 2.26.3