06238772f5
commit 12c20c65d0460cf34f9a665d8f0c0d77d45a3829 upstream.
Commit 77a06c33a22d ("eventfs: Test for ei->is_freed when accessing
ei->dentry") added another check, testing if the parent was freed after
we released the mutex. If so, the function returns NULL. However, all
callers expect it to either return a valid pointer or an error pointer,
at least since commit 5264a2f4bb3b ("tracing: Fix a NULL vs IS_ERR() bug
in event_subsystem_dir()"). Returning NULL will therefore fail the error
condition check in the caller.
Fix this by substituting the NULL return value with a fitting error
pointer.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: stable@vger.kernel.org
Fixes: 77a06c33a22d ("eventfs: Test for ei->is_freed when accessing ei->dentry")
Link: https://lore.kernel.org/20240723122522.2724-1-minipli@grsecurity.net
Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Ajay Kaher <ajay.kaher@broadcom.com>
Signed-off-by: Mathias Krause <minipli@grsecurity.net>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.