f4ba55411c
No upstream commit exists for this commit.
The issue was introduced with backporting upstream commit c16bda37594f
("io_uring/poll: allow some retries for poll triggering spuriously").
Memory allocation can possibly fail causing invalid pointer be
dereferenced just before comparing it to NULL value.
Move the pointer check in proper place (upstream has the similar location
of the check). In case the request has REQ_F_POLLED flag up, apoll can't
be NULL so no need to check there.
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
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 Restructured Text 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.