1 files changed, 17 insertions, 2 deletions

diff --git a/fs/exec.c b/fs/exec.c
index 3cf2cfced97a..fdf53f0c421b 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1275,8 +1275,22 @@ EXPORT_SYMBOL(flush_old_exec);
 
 void would_dump(struct linux_binprm *bprm, struct file *file)
 {
-	if (inode_permission(file_inode(file), MAY_READ) < 0)
+	struct inode *inode = file_inode(file);
+	if (inode_permission(inode, MAY_READ) < 0) {
+		struct user_namespace *old, *user_ns;
 		bprm->interp_flags |= BINPRM_FLAGS_ENFORCE_NONDUMP;
+
+		/* Ensure mm->user_ns contains the executable */
+		user_ns = old = bprm->mm->user_ns;
+		while ((user_ns != &init_user_ns) &&
+		       !privileged_wrt_inode_uidgid(user_ns, inode))
+			user_ns = user_ns->parent;
+
+		if (old != user_ns) {
+			bprm->mm->user_ns = get_user_ns(user_ns);
+			put_user_ns(old);
+		}
+	}
 }
 EXPORT_SYMBOL(would_dump);
 
@@ -1306,7 +1320,6 @@ void setup_new_exec(struct linux_binprm * bprm)
 	    !gid_eq(bprm->cred->gid, current_egid())) {
 		current->pdeath_signal = 0;
 	} else {
-		would_dump(bprm, bprm->file);
 		if (bprm->interp_flags & BINPRM_FLAGS_ENFORCE_NONDUMP)
 			set_dumpable(current->mm, suid_dumpable);
 	}
@@ -1741,6 +1754,8 @@ static int do_execveat_common(int fd, struct filename *filename,
 	if (retval < 0)
 		goto out;
 
+	would_dump(bprm, bprm->file);
+
 	retval = exec_binprm(bprm);
 	if (retval < 0)
 		goto out;