Go to file
Davidlohr Bueso dc2c8c84de ipc: get rid of ids->tables_initialized hack
In sysvipc we have an ids->tables_initialized regarding the rhashtable,
introduced in 0cfb6aee70 ("ipc: optimize semget/shmget/msgget for lots
of keys")

It's there, specifically, to prevent nil pointer dereferences, from using
an uninitialized api.  Considering how rhashtable_init() can fail
(probably due to ENOMEM, if anything), this made the overall ipc
initialization capable of failure as well.  That alone is ugly, but fine,
however I've spotted a few issues regarding the semantics of
tables_initialized (however unlikely they may be):

- There is inconsistency in what we return to userspace: ipc_addid()
  returns ENOSPC which is certainly _wrong_, while ipc_obtain_object_idr()
  returns EINVAL.

- After we started using rhashtables, ipc_findkey() can return nil upon
  !tables_initialized, but the caller expects nil for when the ipc
  structure isn't found, and can therefore call into ipcget() callbacks.

Now that rhashtable initialization cannot fail, we can properly get rid of
the hack altogether.

[manfred@colorfullife.com: commit id extended to 12 digits]
Link: http://lkml.kernel.org/r/20180712185241.4017-10-manfred@colorfullife.com
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Kees Cook <keescook@chromium.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22 10:52:52 -07:00
Documentation ipc: reorganize initialization of kern_ipc_perm.seq 2018-08-22 10:52:51 -07:00
LICENSES LICENSES: Add Linux-OpenIB license text 2018-04-27 16:41:53 -06:00
arch module: use relative references for __ksymtab entries 2018-08-22 10:52:47 -07:00
block for-4.19/block-20180812 2018-08-14 10:23:25 -07:00
certs Replace magic for trusting the secondary keyring with #define 2018-08-16 09:57:20 -07:00
crypto DMAengine updates for v4.19-rc1 2018-08-18 15:55:59 -07:00
drivers drivers/rapidio/devices/rio_mport_cdev.c: remove redundant pointer md 2018-08-22 10:52:51 -07:00
firmware kbuild: remove all dummy assignments to obj- 2017-11-18 11:46:06 +09:00
fs fs/sysv/inode.c: use ktime_get_real_seconds() for superblock stamp 2018-08-22 10:52:51 -07:00
include ipc: get rid of ids->tables_initialized hack 2018-08-22 10:52:52 -07:00
init init/Kconfig: remove EXPERT from CHECKPOINT_RESTORE 2018-08-22 10:52:51 -07:00
ipc ipc: get rid of ids->tables_initialized hack 2018-08-22 10:52:52 -07:00
kernel kernel/sysctl.c: fix typos in comments 2018-08-22 10:52:51 -07:00
lib lib/rhashtable: guarantee initial hashtable allocation 2018-08-22 10:52:52 -07:00
mm bdi: use irqsave variant of refcount_dec_and_lock() 2018-08-22 10:52:46 -07:00
net The main things are support for cephx v2 authentication protocol and 2018-08-20 18:26:55 -07:00
samples samples/bpf: all XDP samples should unload xdp/bpf prog on SIGTERM 2018-08-16 21:55:32 +02:00
scripts checkpatch: DT bindings should be a separate patch 2018-08-22 10:52:49 -07:00
security init: allow initcall tables to be emitted using relative references 2018-08-22 10:52:47 -07:00
sound DMAengine updates for v4.19-rc1 2018-08-18 15:55:59 -07:00
tools proc: test /proc/thread-self symlink 2018-08-22 10:52:45 -07:00
usr kbuild: rename built-in.o to built-in.a 2018-03-26 02:01:19 +09:00
virt mm, oom: distinguish blockable mode for mmu notifiers 2018-08-22 10:52:44 -07:00
.clang-format clang-format: Set IndentWrappedFunctionNames false 2018-08-01 18:38:51 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore Kbuild updates for v4.17 (2nd) 2018-04-15 17:21:30 -07:00
.mailmap Merge branch 'linus/master' into rdma.git for-next 2018-08-16 14:21:29 -06:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS 9p: remove Ron Minnich from MAINTAINERS 2018-08-17 16:20:26 -07:00
Kbuild Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Kconfig kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt 2018-08-02 08:06:55 +09:00
MAINTAINERS - New Drivers 2018-08-20 15:38:44 -07:00
Makefile Updates for v4.19: 2018-08-20 18:32:00 -07:00
README Docs: Added a pointer to the formatted docs to README 2018-03-21 09:02:53 -06:00

README

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.
See Documentation/00-INDEX for a list of what is contained in each file.

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.