ladybird/Kernel/Syscalls/access.cpp

/*
 * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

#include <AK/StringView.h>
#include <Kernel/FileSystem/VirtualFileSystem.h>
#include <Kernel/Process.h>

namespace Kernel {

ErrorOr<FlatPtr> Process::sys$access(Userspace<char const*> user_path, size_t path_length, int mode)
{
    VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this);
    TRY(require_promise(Pledge::rpath));
    auto path = TRY(get_syscall_path_argument(user_path, path_length));
    TRY(VirtualFileSystem::the().access(credentials(), path->view(), mode, current_directory()));
    return 0;
}

}
Kernel: Move syscall implementations out of Process.cpp This is something I've been meaning to do for a long time, and here we finally go. This patch moves all sys$foo functions out of Process.cpp and into files in Kernel/Syscalls/. It's not exactly one syscall per file (although it could be, but I got a bit tired of the repetitive work here..) This makes hacking on individual syscalls a lot less painful since you don't have to rebuild nearly as much code every time. I'm also hopeful that this makes it easier to understand individual syscalls. :^) 2020-07-31 00:38:15 +03:00			`/*`
			`* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>`
			`*`
Everything: Move to SPDX license identifiers in all files. SPDX License Identifiers are a more compact / standardized way of representing file license information. See: https://spdx.dev/resources/use/#identifiers This was done with the `ambr` search and replace tool. ambr --no-parent-ignore --key-from-file --rep-from-file key.txt rep.txt * 2021-04-22 11:24:48 +03:00			`* SPDX-License-Identifier: BSD-2-Clause`
Kernel: Move syscall implementations out of Process.cpp This is something I've been meaning to do for a long time, and here we finally go. This patch moves all sys$foo functions out of Process.cpp and into files in Kernel/Syscalls/. It's not exactly one syscall per file (although it could be, but I got a bit tired of the repetitive work here..) This makes hacking on individual syscalls a lot less painful since you don't have to rebuild nearly as much code every time. I'm also hopeful that this makes it easier to understand individual syscalls. :^) 2020-07-31 00:38:15 +03:00			`*/`

			`#include <AK/StringView.h>`
			`#include <Kernel/FileSystem/VirtualFileSystem.h>`
			`#include <Kernel/Process.h>`

			`namespace Kernel {`

Everywhere: Run clang-format 2022-04-01 20:58:27 +03:00			`ErrorOr<FlatPtr> Process::sys$access(Userspace<char const*> user_path, size_t path_length, int mode)`
Kernel: Move syscall implementations out of Process.cpp This is something I've been meaning to do for a long time, and here we finally go. This patch moves all sys$foo functions out of Process.cpp and into files in Kernel/Syscalls/. It's not exactly one syscall per file (although it could be, but I got a bit tired of the repetitive work here..) This makes hacking on individual syscalls a lot less painful since you don't have to rebuild nearly as much code every time. I'm also hopeful that this makes it easier to understand individual syscalls. :^) 2020-07-31 00:38:15 +03:00			`{`
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. 2021-07-18 21:20:12 +03:00			`VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this);`
Kernel: Handle promise violations in the syscall handler Previously we would crash the process immediately when a promise violation was found during a syscall. This is error prone, as we don't unwind the stack. This means that in certain cases we can leak resources, like an OwnPtr / RefPtr tracked on the stack. Or even leak a lock acquired in a ScopeLockLocker. To remedy this situation we move the promise violation handling to the syscall handler, right before we return to user space. This allows the code to follow the normal unwind path, and grantees there is no longer any cleanup that needs to occur. The Process::require_promise() and Process::require_no_promises() functions were modified to return ErrorOr<void> so we enforce that the errors are always propagated by the caller. 2021-12-29 12:11:45 +03:00			`TRY(require_promise(Pledge::rpath));`
Kernel: Use TRY() in sys$access() 2021-09-05 17:04:55 +03:00			`auto path = TRY(get_syscall_path_argument(user_path, path_length));`
Kernel: Make VirtualFileSystem functions take credentials as input Instead of getting credentials from Process::current(), we now require that they be provided as input to the various VFS functions. This ensures that an atomic set of credentials is used throughout an entire VFS operation. 2022-08-21 17:02:24 +03:00			`TRY(VirtualFileSystem::the().access(credentials(), path->view(), mode, current_directory()));`
Kernel: Replace KResult and KResultOr<T> with Error and ErrorOr<T> We now use AK::Error and AK::ErrorOr<T> in both kernel and userspace! This was a slightly tedious refactoring that took a long time, so it's not unlikely that some bugs crept in. Nevertheless, it does pass basic functionality testing, and it's just real nice to finally see the same pattern in all contexts. :^) 2021-11-08 02:51:39 +03:00			`return 0;`
Kernel: Move syscall implementations out of Process.cpp This is something I've been meaning to do for a long time, and here we finally go. This patch moves all sys$foo functions out of Process.cpp and into files in Kernel/Syscalls/. It's not exactly one syscall per file (although it could be, but I got a bit tired of the repetitive work here..) This makes hacking on individual syscalls a lot less painful since you don't have to rebuild nearly as much code every time. I'm also hopeful that this makes it easier to understand individual syscalls. :^) 2020-07-31 00:38:15 +03:00			`}`

			`}`