429a22e776
At the moment, the binfmt_elf and binfmt_elf_fdpic code have slightly different code to figure out which VMAs should be dumped, and if so, whether the dump should contain the entire VMA or just its first page. Eliminate duplicate code by reworking the binfmt_elf version into a generic core dumping helper in coredump.c. As part of that, change the heuristic for detecting executable/library header pages to check whether the inode is executable instead of looking at the file mode. This is less problematic in terms of locking because it lets us avoid get_user() under the mmap_sem. (And arguably it looks nicer and makes more sense in generic code.) Adjust a little bit based on the binfmt_elf_fdpic version: ->anon_vma is only meaningful under CONFIG_MMU, otherwise we have to assume that the VMA has been written to. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Jann Horn <jannh@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: "Eric W . Biederman" <ebiederm@xmission.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Hugh Dickins <hughd@google.com> Link: http://lkml.kernel.org/r/20200827114932.3572699-5-jannh@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.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.