mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-04-29 11:44:39 -04:00
4ea51e0e37
Pull close_range() fix from Christian Brauner: "Syzbot reported a bug in close_range. Debugging this showed we didn't recalculate the current maximum fd number for CLOSE_RANGE_UNSHARE | CLOSE_RANGE_CLOEXEC after we unshared the file descriptors table. As a result, max_fd could exceed the current fdtable maximum causing us to set excessive bits. As a concrete example, let's say the user requested everything from fd 4 to ~0UL to be closed and their current fdtable size is 256 with their highest open fd being 4. With CLOSE_RANGE_UNSHARE the caller will end up with a new fdtable which has room for 64 file descriptors since that is the lowest fdtable size we accept. But now max_fd will still point to 255 and needs to be adjusted. Fix this by retrieving the correct maximum fd value in __range_cloexec(). I've carried this fix for a little while but since there was no linux-next release over easter I waited until now. With this change close_range() can be further simplified but imho we are in no hurry to do that and so I'll defer this for the 5.13 merge window" * tag 'for-linus-2021-04-08' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: file: fix close_range() for unshare+cloexec
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.