* nix/libstore/build.cc (DerivationGoal::runChild): Remount ‘target’ as
read-only.
Reported-by: Reepca Russelstein <reepca@russelstein.xyz>
Change-Id: Ib7201bcf4363be566f205d23d17fe2f55d3ad666
---
nix/libstore/build.cc | 7 +++++++
1 file changed, 7 insertions(+)
@@ -2107,8 +2107,15 @@ void DerivationGoal::runChild()
createDirs(dirOf(target));
writeFile(target, "");
}
+
+ /* Extra flags passed with MS_BIND are ignored, hence the
+ extra MS_REMOUNT. */
if (mount(source.c_str(), target.c_str(), "", MS_BIND, 0) == -1)
throw SysError(format("bind mount from `%1%' to `%2%' failed") % source % target);
+ if (source.compare(0, settings.nixStore.length(), settings.nixStore) == 0) {
+ if (mount(source.c_str(), target.c_str(), "", MS_BIND | MS_REMOUNT | MS_RDONLY, 0) == -1)
+ throw SysError(format("read-only remount of `%1%' failed") % target);
+ }
}
/* Bind a new instance of procfs on /proc to reflect our