ladybird/Kernel/Syscalls/setuid.cpp
Brian Gianforcaro 9201a06027 Kernel: Annotate all syscalls with VERIFY_PROCESS_BIG_LOCK_ACQUIRED
Before we start disabling acquisition of the big process lock for
specific syscalls, make sure to document and assert that all the
lock is held during all syscalls.
2021-07-20 03:21:14 +02:00

196 lines
4.7 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <Kernel/Process.h>
namespace Kernel {
KResultOr<FlatPtr> Process::sys$seteuid(uid_t new_euid)
{
VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this)
REQUIRE_PROMISE(id);
if (new_euid != uid() && new_euid != suid() && !is_superuser())
return EPERM;
if (euid() != new_euid)
set_dumpable(false);
ProtectedDataMutationScope scope { *this };
m_euid = new_euid;
return 0;
}
KResultOr<FlatPtr> Process::sys$setegid(gid_t new_egid)
{
VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this)
REQUIRE_PROMISE(id);
if (new_egid != gid() && new_egid != sgid() && !is_superuser())
return EPERM;
if (egid() != new_egid)
set_dumpable(false);
ProtectedDataMutationScope scope { *this };
m_egid = new_egid;
return 0;
}
KResultOr<FlatPtr> Process::sys$setuid(uid_t new_uid)
{
VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this)
REQUIRE_PROMISE(id);
if (new_uid != uid() && new_uid != euid() && !is_superuser())
return EPERM;
if (euid() != new_uid)
set_dumpable(false);
ProtectedDataMutationScope scope { *this };
m_uid = new_uid;
m_euid = new_uid;
m_suid = new_uid;
return 0;
}
KResultOr<FlatPtr> Process::sys$setgid(gid_t new_gid)
{
VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this)
REQUIRE_PROMISE(id);
if (new_gid != gid() && new_gid != egid() && !is_superuser())
return EPERM;
if (egid() != new_gid)
set_dumpable(false);
ProtectedDataMutationScope scope { *this };
m_gid = new_gid;
m_egid = new_gid;
m_sgid = new_gid;
return 0;
}
KResultOr<FlatPtr> Process::sys$setreuid(uid_t new_ruid, uid_t new_euid)
{
VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this)
REQUIRE_PROMISE(id);
if (new_ruid == (uid_t)-1)
new_ruid = uid();
if (new_euid == (uid_t)-1)
new_euid = euid();
auto ok = [this](uid_t id) { return id == uid() || id == euid() || id == suid(); };
if (!ok(new_ruid) || !ok(new_euid))
return EPERM;
if (new_ruid < (uid_t)-1 || new_euid < (uid_t)-1)
return EINVAL;
if (euid() != new_euid)
set_dumpable(false);
ProtectedDataMutationScope scope { *this };
m_uid = new_ruid;
m_euid = new_euid;
return 0;
}
KResultOr<FlatPtr> Process::sys$setresuid(uid_t new_ruid, uid_t new_euid, uid_t new_suid)
{
VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this)
REQUIRE_PROMISE(id);
if (new_ruid == (uid_t)-1)
new_ruid = uid();
if (new_euid == (uid_t)-1)
new_euid = euid();
if (new_suid == (uid_t)-1)
new_suid = suid();
auto ok = [this](uid_t id) { return id == uid() || id == euid() || id == suid(); };
if ((!ok(new_ruid) || !ok(new_euid) || !ok(new_suid)) && !is_superuser())
return EPERM;
if (euid() != new_euid)
set_dumpable(false);
ProtectedDataMutationScope scope { *this };
m_uid = new_ruid;
m_euid = new_euid;
m_suid = new_suid;
return 0;
}
KResultOr<FlatPtr> Process::sys$setresgid(gid_t new_rgid, gid_t new_egid, gid_t new_sgid)
{
VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this)
REQUIRE_PROMISE(id);
if (new_rgid == (gid_t)-1)
new_rgid = gid();
if (new_egid == (gid_t)-1)
new_egid = egid();
if (new_sgid == (gid_t)-1)
new_sgid = sgid();
auto ok = [this](gid_t id) { return id == gid() || id == egid() || id == sgid(); };
if ((!ok(new_rgid) || !ok(new_egid) || !ok(new_sgid)) && !is_superuser())
return EPERM;
if (egid() != new_egid)
set_dumpable(false);
ProtectedDataMutationScope scope { *this };
m_gid = new_rgid;
m_egid = new_egid;
m_sgid = new_sgid;
return 0;
}
KResultOr<FlatPtr> Process::sys$setgroups(size_t count, Userspace<const gid_t*> user_gids)
{
VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this)
REQUIRE_PROMISE(id);
if (!is_superuser())
return EPERM;
if (!count) {
ProtectedDataMutationScope scope { *this };
m_extra_gids.clear();
return 0;
}
Vector<gid_t> new_extra_gids;
if (!new_extra_gids.try_resize(count))
return ENOMEM;
if (!copy_n_from_user(new_extra_gids.data(), user_gids, count))
return EFAULT;
HashTable<gid_t> unique_extra_gids;
for (auto& extra_gid : new_extra_gids) {
if (extra_gid != gid())
unique_extra_gids.set(extra_gid);
}
ProtectedDataMutationScope scope { *this };
if (!m_extra_gids.try_resize(unique_extra_gids.size()))
return ENOMEM;
size_t i = 0;
for (auto& extra_gid : unique_extra_gids) {
if (extra_gid == gid())
continue;
m_extra_gids[i++] = extra_gid;
}
return 0;
}
}