Handle hard links to other files in the output

This commit is contained in:
Eelco Dolstra 2013-02-27 17:18:41 +01:00
parent b008674e46
commit 0111ba98ea
2 changed files with 36 additions and 6 deletions

View file

@ -6,6 +6,16 @@
<!--==================================================================-->
<section xml:id="ssec-relnotes-1.5"><title>Release 1.5 (February 27, 2013)</title>
<para>This is a brown paper bag release to fix a regression introduced
by the hard link security fix in 1.4.</para>
</section>
<!--==================================================================--> <!--==================================================================-->
<section xml:id="ssec-relnotes-1.4"><title>Release 1.4 (February 26, 2013)</title> <section xml:id="ssec-relnotes-1.4"><title>Release 1.4 (February 26, 2013)</title>

View file

@ -509,7 +509,11 @@ void canonicaliseTimestampAndPermissions(const Path & path)
} }
static void canonicalisePathMetaData_(const Path & path, uid_t fromUid) typedef std::pair<dev_t, ino_t> Inode;
typedef set<Inode> InodesSeen;
static void canonicalisePathMetaData_(const Path & path, uid_t fromUid, InodesSeen & inodesSeen)
{ {
checkInterrupt(); checkInterrupt();
@ -521,10 +525,24 @@ static void canonicalisePathMetaData_(const Path & path, uid_t fromUid)
has already been checked in dumpPath(). */ has already been checked in dumpPath(). */
assert(S_ISREG(st.st_mode) || S_ISDIR(st.st_mode) || S_ISLNK(st.st_mode)); assert(S_ISREG(st.st_mode) || S_ISDIR(st.st_mode) || S_ISLNK(st.st_mode));
canonicaliseTimestampAndPermissions(path, st); /* Fail if the file is not owned by the build user. This prevents
us from messing up the ownership/permissions of files
hard-linked into the output (e.g. "ln /etc/shadow $out/foo").
However, ignore files that we chown'ed ourselves previously to
ensure that we don't fail on hard links within the same build
(i.e. "touch $out/foo; ln $out/foo $out/bar"). */
if (fromUid != (uid_t) -1 && st.st_uid != fromUid) {
assert(!S_ISDIR(st.st_mode));
if (inodesSeen.find(Inode(st.st_dev, st.st_ino)) == inodesSeen.end())
throw BuildError(format("invalid ownership on file `%1%'") % path);
mode_t mode = st.st_mode & ~S_IFMT;
assert(st.st_uid == geteuid() && (mode == 0444 || mode == 0555) && st.st_mtime == mtimeStore);
return;
}
if (fromUid != (uid_t) -1 && st.st_uid != fromUid) inodesSeen.insert(Inode(st.st_dev, st.st_ino));
throw BuildError(format("invalid ownership on file `%1%'") % path);
canonicaliseTimestampAndPermissions(path, st);
/* Change ownership to the current uid. If it's a symlink, use /* Change ownership to the current uid. If it's a symlink, use
lchown if available, otherwise don't bother. Wrong ownership lchown if available, otherwise don't bother. Wrong ownership
@ -547,14 +565,16 @@ static void canonicalisePathMetaData_(const Path & path, uid_t fromUid)
if (S_ISDIR(st.st_mode)) { if (S_ISDIR(st.st_mode)) {
Strings names = readDirectory(path); Strings names = readDirectory(path);
foreach (Strings::iterator, i, names) foreach (Strings::iterator, i, names)
canonicalisePathMetaData_(path + "/" + *i, fromUid); canonicalisePathMetaData_(path + "/" + *i, fromUid, inodesSeen);
} }
} }
void canonicalisePathMetaData(const Path & path, uid_t fromUid) void canonicalisePathMetaData(const Path & path, uid_t fromUid)
{ {
canonicalisePathMetaData_(path, fromUid); InodesSeen inodesSeen;
canonicalisePathMetaData_(path, fromUid, inodesSeen);
/* On platforms that don't have lchown(), the top-level path can't /* On platforms that don't have lchown(), the top-level path can't
be a symlink, since we can't change its ownership. */ be a symlink, since we can't change its ownership. */