]> git.proxmox.com Git - mirror_ubuntu-kernels.git/commit
pid: Replace struct pid 1-element array with flex-array
authorKees Cook <keescook@chromium.org>
Fri, 30 Jun 2023 07:46:17 +0000 (09:46 +0200)
committerLinus Torvalds <torvalds@linux-foundation.org>
Fri, 30 Jun 2023 16:04:01 +0000 (09:04 -0700)
commitb69f0aeb068980af983d399deafc7477cec8bc04
tree9ed5c782849059b2cc6bccde1306b8bd908d51f4
parent112e7e21519422b6f2bb0fa8061f5685e9757170
pid: Replace struct pid 1-element array with flex-array

For pid namespaces, struct pid uses a dynamically sized array member,
"numbers".  This was implemented using the ancient 1-element fake
flexible array, which has been deprecated for decades.

Replace it with a C99 flexible array, refactor the array size
calculations to use struct_size(), and address elements via indexes.
Note that the static initializer (which defines a single element) works
as-is, and requires no special handling.

Without this, CONFIG_UBSAN_BOUNDS (and potentially
CONFIG_FORTIFY_SOURCE) will trigger bounds checks:

  https://lore.kernel.org/lkml/20230517-bushaltestelle-super-e223978c1ba6@brauner

Cc: Christian Brauner <brauner@kernel.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Jeff Xu <jeffxu@google.com>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Daniel Verkamp <dverkamp@chromium.org>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Jeff Xu <jeffxu@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Frederic Weisbecker <frederic@kernel.org>
Reported-by: syzbot+ac3b41786a2d0565b6d5@syzkaller.appspotmail.com
[brauner: dropped unrelated changes and remove 0 with NULL cast]
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
include/linux/pid.h
kernel/pid.c
kernel/pid_namespace.c