forked from lix-project/lix
Refactoring: Split off the non-recursive canonicalisePathMetaData()
Also, change the file mode before changing the owner. This prevents a slight time window in which a setuid binary would be setuid root.
This commit is contained in:
parent
826dc0d07d
commit
b008674e46
|
@ -465,39 +465,8 @@ void LocalStore::makeStoreWritable()
|
||||||
const time_t mtimeStore = 1; /* 1 second into the epoch */
|
const time_t mtimeStore = 1; /* 1 second into the epoch */
|
||||||
|
|
||||||
|
|
||||||
void canonicalisePathMetaData(const Path & path, bool recurse, uid_t fromUid)
|
static void canonicaliseTimestampAndPermissions(const Path & path, const struct stat & st)
|
||||||
{
|
{
|
||||||
checkInterrupt();
|
|
||||||
|
|
||||||
struct stat st;
|
|
||||||
if (lstat(path.c_str(), &st))
|
|
||||||
throw SysError(format("getting attributes of path `%1%'") % path);
|
|
||||||
|
|
||||||
/* Really make sure that the path is of a supported type. This
|
|
||||||
has already been checked in dumpPath(). */
|
|
||||||
assert(S_ISREG(st.st_mode) || S_ISDIR(st.st_mode) || S_ISLNK(st.st_mode));
|
|
||||||
|
|
||||||
if (fromUid != (uid_t) -1 && st.st_uid != fromUid)
|
|
||||||
throw BuildError(format("invalid ownership on file `%1%'") % path);
|
|
||||||
|
|
||||||
/* Change ownership to the current uid. If it's a symlink, use
|
|
||||||
lchown if available, otherwise don't bother. Wrong ownership
|
|
||||||
of a symlink doesn't matter, since the owning user can't change
|
|
||||||
the symlink and can't delete it because the directory is not
|
|
||||||
writable. The only exception is top-level paths in the Nix
|
|
||||||
store (since that directory is group-writable for the Nix build
|
|
||||||
users group); we check for this case below. */
|
|
||||||
if (st.st_uid != geteuid()) {
|
|
||||||
#if HAVE_LCHOWN
|
|
||||||
if (lchown(path.c_str(), geteuid(), (gid_t) -1) == -1)
|
|
||||||
#else
|
|
||||||
if (!S_ISLNK(st.st_mode) &&
|
|
||||||
chown(path.c_str(), geteuid(), (gid_t) -1) == -1)
|
|
||||||
#endif
|
|
||||||
throw SysError(format("changing owner of `%1%' to %2%")
|
|
||||||
% path % geteuid());
|
|
||||||
}
|
|
||||||
|
|
||||||
if (!S_ISLNK(st.st_mode)) {
|
if (!S_ISLNK(st.st_mode)) {
|
||||||
|
|
||||||
/* Mask out all type related bits. */
|
/* Mask out all type related bits. */
|
||||||
|
@ -528,18 +497,64 @@ void canonicalisePathMetaData(const Path & path, bool recurse, uid_t fromUid)
|
||||||
#endif
|
#endif
|
||||||
throw SysError(format("changing modification time of `%1%'") % path);
|
throw SysError(format("changing modification time of `%1%'") % path);
|
||||||
}
|
}
|
||||||
|
}
|
||||||
|
|
||||||
if (recurse && S_ISDIR(st.st_mode)) {
|
|
||||||
|
void canonicaliseTimestampAndPermissions(const Path & path)
|
||||||
|
{
|
||||||
|
struct stat st;
|
||||||
|
if (lstat(path.c_str(), &st))
|
||||||
|
throw SysError(format("getting attributes of path `%1%'") % path);
|
||||||
|
canonicaliseTimestampAndPermissions(path, st);
|
||||||
|
}
|
||||||
|
|
||||||
|
|
||||||
|
static void canonicalisePathMetaData_(const Path & path, uid_t fromUid)
|
||||||
|
{
|
||||||
|
checkInterrupt();
|
||||||
|
|
||||||
|
struct stat st;
|
||||||
|
if (lstat(path.c_str(), &st))
|
||||||
|
throw SysError(format("getting attributes of path `%1%'") % path);
|
||||||
|
|
||||||
|
/* Really make sure that the path is of a supported type. This
|
||||||
|
has already been checked in dumpPath(). */
|
||||||
|
assert(S_ISREG(st.st_mode) || S_ISDIR(st.st_mode) || S_ISLNK(st.st_mode));
|
||||||
|
|
||||||
|
canonicaliseTimestampAndPermissions(path, st);
|
||||||
|
|
||||||
|
if (fromUid != (uid_t) -1 && st.st_uid != fromUid)
|
||||||
|
throw BuildError(format("invalid ownership on file `%1%'") % path);
|
||||||
|
|
||||||
|
/* Change ownership to the current uid. If it's a symlink, use
|
||||||
|
lchown if available, otherwise don't bother. Wrong ownership
|
||||||
|
of a symlink doesn't matter, since the owning user can't change
|
||||||
|
the symlink and can't delete it because the directory is not
|
||||||
|
writable. The only exception is top-level paths in the Nix
|
||||||
|
store (since that directory is group-writable for the Nix build
|
||||||
|
users group); we check for this case below. */
|
||||||
|
if (st.st_uid != geteuid()) {
|
||||||
|
#if HAVE_LCHOWN
|
||||||
|
if (lchown(path.c_str(), geteuid(), (gid_t) -1) == -1)
|
||||||
|
#else
|
||||||
|
if (!S_ISLNK(st.st_mode) &&
|
||||||
|
chown(path.c_str(), geteuid(), (gid_t) -1) == -1)
|
||||||
|
#endif
|
||||||
|
throw SysError(format("changing owner of `%1%' to %2%")
|
||||||
|
% path % geteuid());
|
||||||
|
}
|
||||||
|
|
||||||
|
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, true, fromUid);
|
canonicalisePathMetaData_(path + "/" + *i, fromUid);
|
||||||
}
|
}
|
||||||
}
|
}
|
||||||
|
|
||||||
|
|
||||||
void canonicalisePathMetaData(const Path & path, uid_t fromUid)
|
void canonicalisePathMetaData(const Path & path, uid_t fromUid)
|
||||||
{
|
{
|
||||||
canonicalisePathMetaData(path, true, fromUid);
|
canonicalisePathMetaData_(path, fromUid);
|
||||||
|
|
||||||
/* 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. */
|
||||||
|
|
|
@ -309,7 +309,7 @@ private:
|
||||||
in a setuid Nix installation. */
|
in a setuid Nix installation. */
|
||||||
void canonicalisePathMetaData(const Path & path, uid_t fromUid);
|
void canonicalisePathMetaData(const Path & path, uid_t fromUid);
|
||||||
|
|
||||||
void canonicalisePathMetaData(const Path & path, bool recurse, uid_t fromUid);
|
void canonicaliseTimestampAndPermissions(const Path & path);
|
||||||
|
|
||||||
MakeError(PathInUse, Error);
|
MakeError(PathInUse, Error);
|
||||||
|
|
||||||
|
|
|
@ -32,7 +32,7 @@ struct MakeReadOnly
|
||||||
{
|
{
|
||||||
try {
|
try {
|
||||||
/* This will make the path read-only. */
|
/* This will make the path read-only. */
|
||||||
if (path != "") canonicalisePathMetaData(path, false, -1);
|
if (path != "") canonicaliseTimestampAndPermissions(path);
|
||||||
} catch (...) {
|
} catch (...) {
|
||||||
ignoreException();
|
ignoreException();
|
||||||
}
|
}
|
||||||
|
|
Loading…
Reference in a new issue