Kernel: Update process promise states on execve() and fork()

We now move the execpromises state into the regular promises, and clear
the execpromises state.

Also make sure to duplicate the promise state on fork.

This fixes an issue where "su" would launch a shell which immediately
crashed due to not having pledged "stdio".

4 files changed, 10 insertions, 1 deletions

diff --git a/Kernel/Process.h b/Kernel/Process.h
index 3acafcccbb..c761bbabf0 100644
--- a/Kernel/Process.h
+++ b/Kernel/Process.h
@@ -637,6 +637,7 @@ private:
 
     bool m_has_promises { false };
     u32 m_promises { 0 };
+    bool m_has_execpromises { false };
     u32 m_execpromises { 0 };
 
     VeilState m_veil_state { VeilState::None };
diff --git a/Kernel/Syscalls/execve.cpp b/Kernel/Syscalls/execve.cpp
index 1348582663..b6ebe30e66 100644
--- a/Kernel/Syscalls/execve.cpp
+++ b/Kernel/Syscalls/execve.cpp
@@ -544,6 +544,10 @@ int Process::do_exec(NonnullRefPtr<FileDescription> main_program_description, Ve
     m_environment = environment;
 
     m_promises = m_execpromises;
+    m_has_promises = m_has_execpromises;
+
+    m_execpromises = 0;
+    m_has_execpromises = false;
 
     m_veil_state = VeilState::None;
     m_unveiled_paths.clear();
diff --git a/Kernel/Syscalls/fork.cpp b/Kernel/Syscalls/fork.cpp
index edf359c3a5..db600ee562 100644
--- a/Kernel/Syscalls/fork.cpp
+++ b/Kernel/Syscalls/fork.cpp
@@ -43,6 +43,8 @@ pid_t Process::sys$fork(RegisterState& regs)
     child->m_root_directory_relative_to_global_root = m_root_directory_relative_to_global_root;
     child->m_promises = m_promises;
     child->m_execpromises = m_execpromises;
+    child->m_has_promises = m_has_promises;
+    child->m_has_execpromises = m_has_execpromises;
     child->m_veil_state = m_veil_state;
     child->m_unveiled_paths = m_unveiled_paths.deep_copy();
     child->m_fds = m_fds;
diff --git a/Kernel/Syscalls/pledge.cpp b/Kernel/Syscalls/pledge.cpp
index d101295ee7..0613ab575e 100644
--- a/Kernel/Syscalls/pledge.cpp
+++ b/Kernel/Syscalls/pledge.cpp
@@ -84,7 +84,9 @@ int Process::sys$pledge(Userspace<const Syscall::SC_pledge_params*> user_params)
             return -EPERM;
     }
 
-    m_has_promises = true;
+    m_has_promises = m_has_promises || !promises.is_null();
+    m_has_execpromises = m_has_execpromises || !execpromises.is_null();
+
     m_promises = new_promises;
     m_execpromises = new_execpromises;