1
Fork 0
mirror of https://github.com/RGBCube/serenity synced 2025-05-31 10:18:11 +00:00

Kernel+SystemServer+CrashDaemon: Better control where we put core dumps

SystemServer now creates the /tmp/coredump and /tmp/profiler_coredumps
directories at startup, ensuring that they are owned by root, and with
basic 0755 permissions.

The kernel will also now refuse to put core dumps in a directory that
doesn't fulfill the following criteria:

- Owned by 0:0
- Directory with sticky bit not set
- 0755 permissions

Fixes #4435
Fixes #4850
This commit is contained in:
Andreas Kling 2021-01-10 11:27:02 +01:00
parent f152b6f7ed
commit 190e0e1551
3 changed files with 40 additions and 12 deletions

View file

@ -69,23 +69,27 @@ RefPtr<FileDescription> CoreDump::create_target_file(const Process& process, con
{
LexicalPath lexical_path(output_path);
auto output_directory = lexical_path.dirname();
if (VFS::the().open_directory(output_directory, VFS::the().root_custody()).is_error()) {
auto res = VFS::the().mkdir(output_directory, 0777, VFS::the().root_custody());
if (res.is_error())
return nullptr;
}
auto tmp_dir = VFS::the().open_directory(output_directory, VFS::the().root_custody());
if (tmp_dir.is_error())
auto dump_directory = VFS::the().open_directory(output_directory, VFS::the().root_custody());
if (dump_directory.is_error()) {
dbgln("Can't find directory '{}' for core dump", output_directory);
return nullptr;
}
auto dump_directory_metadata = dump_directory.value()->inode().metadata();
if (dump_directory_metadata.uid != 0 || dump_directory_metadata.gid != 0 || dump_directory_metadata.mode != 040755) {
dbgln("Refusing to put core dump in sketchy directory '{}'", output_directory);
return nullptr;
}
auto fd_or_error = VFS::the().open(
lexical_path.basename(),
O_CREAT | O_WRONLY | O_EXCL,
0, // We will enable reading from userspace when we finish generating the coredump file
*tmp_dir.value(),
*dump_directory.value(),
UidAndGid { process.uid(), process.gid() });
if (fd_or_error.is_error())
if (fd_or_error.is_error()) {
dbgln("Failed to open core dump '{}' for writing", output_path);
return nullptr;
}
return fd_or_error.value();
}