Previously this API would return an InodeIdentifier, which meant that
there was a race in path resolution where an inode could be unlinked
in between finding the InodeIdentifier for a path component, and
actually resolving that to an Inode object.
Attaching a test that would quickly trip an assertion before.
Test: Kernel/path-resolution-race.cpp
This changes copyright holder to myself for the source code files that I've
created or have (almost) completely rewritten. Not included are the files
that were significantly changed by others even though it was me who originally
created them (think HtmlView), or the many other files I've contributed code to.
Before this, we would end up in memcpy() churn hell when a program was
doing repeated write() calls to a file in /tmp.
An even better solution will be to only grow the VM allocation of the
underlying buffer and keep using the same physical pages. This would
eliminate all the memcpy() work.
I've benchmarked this using g++ to compile Kernel/Process.cpp.
With these changes, compilation goes from ~35 sec to ~31 sec. :^)
As suggested by Joshua, this commit adds the 2-clause BSD license as a
comment block to the top of every source file.
For the first pass, I've just added myself for simplicity. I encourage
everyone to add themselves as copyright holders of any file they've
added or modified in some significant way. If I've added myself in
error somewhere, feel free to replace it with the appropriate copyright
holder instead.
Going forward, all new source files should include a license header.
As Sergey pointed out, it's silly to have proper entries for . and ..
in TmpFS when we can just synthesize them on the fly.
Note that we have to tolerate removal of . and .. via remove_child()
to keep VFS::rmdir() happy.
We were running without the sticky bit and mode 777, which meant that
the /tmp directory was world-writable *without* protection.
With this fixed, it's no longer possible for everyone to steal root's
files in /tmp.
If we're creating something that should have a different owner than the
current process's UID/GID, we need to plumb that all the way through
VFS down to the FS functions.
- TmpFSInode::write_bytes() needs to allow non-zero offsets
- TmpFSInode::read_bytes() wasn't respecting the offset
GCC puts the temporary files generated during compilation in /tmp,
so this exposed some bugs in TmpFS.
