tdf#129895: handle symlinks when populating chroot
In linkOrCopy, the nftw() function is used without the FTW_PHYS flag to
populate child roots from systemplate. From man nftw:
FTW_PHYS
If set, do not follow symbolic links. (This is what you want.)
If not set, symbolic links are followed, but no file is reported twice.
Because the order in which directory entries are visited is not defined,
having multiple symlinks to a file results in only one of the paths
being created in the chroot.
This is not really a problem because loolwsd-systemplate-setup creates
systemplate without symlinks. Fixing it might prevent unpleasant
surprises in the future though, and might possibly allow to make
systemplate and chroots smaller (also the manpage says that you want
it:)).
The commit adds FTW_PHYS flag to the call as well as symlink handling.
Change-Id: I01354f529b5d340185988ed026f266caf17a6881
Reviewed-on: https://gerrit.libreoffice.org/c/online/+/87749
Tested-by: Jenkins CollaboraOffice <jenkinscollaboraoffice@gmail.com>
Reviewed-by: Michael Meeks <michael.meeks@collabora.com>
diff --git a/kit/Kit.cpp b/kit/Kit.cpp
index f647f1e..e99ec8e 100644
--- a/kit/Kit.cpp
+++ b/kit/Kit.cpp
@@ -210,7 +210,7 @@
if (link(fpath, newPath.toString().c_str()) == -1)
{
LOG_INF("link(\"" << fpath << "\", \"" <<
newPath.toString() << "\") failed. Will copy.");
newPath.toString() << "\") failed: " << strerror(errno) << ". Will copy.");
try
{
File(fpath).copyTo(newPath.toString());
@@ -226,7 +226,7 @@
}
int linkOrCopyFunction(const char *fpath,
const struct stat* /*sb*/,
const struct stat* sb,
int typeflag,
struct FTW* /*ftwbuf*/)
{
@@ -282,6 +282,22 @@
}
}
break;
case FTW_SL:
{
size_t size = sb->st_size;
char target[size + 1];
ssize_t written = readlink(fpath, target, size);
if (written <= 0 || static_cast<size_t>(written) > size) {
LOG_FTL("readlink(\"" << std::string(fpath) << "\") failed: " << strerror(errno));
Log::shutdown();
std::_Exit(EX_SOFTWARE);
}
target[written] = '\0';
File(newPath.parent()).createDirectories();
File(target).linkTo(newPath.toString(), Poco::File::LinkType::LINK_SYMBOLIC);
}
break;
case FTW_DNR:
LOG_ERR("Cannot read directory '" << fpath << "'");
return 1;
@@ -306,7 +322,7 @@
sourceForLinkOrCopy.pop_back();
destinationForLinkOrCopy = destination;
linkOrCopyStartTime = std::chrono::steady_clock::now();
if (nftw(source.c_str(), linkOrCopyFunction, 10, FTW_ACTIONRETVAL) == -1)
if (nftw(source.c_str(), linkOrCopyFunction, 10, FTW_ACTIONRETVAL|FTW_PHYS) == -1)
{
LOG_ERR("linkOrCopy: nftw() failed for '" << source << "'");
}
