linux-hardened/ipc
Eric W. Biederman ae7795bc61 signal: Distinguish between kernel_siginfo and siginfo
Linus recently observed that if we did not worry about the padding
member in struct siginfo it is only about 48 bytes, and 48 bytes is
much nicer than 128 bytes for allocating on the stack and copying
around in the kernel.

The obvious thing of only adding the padding when userspace is
including siginfo.h won't work as there are sigframe definitions in
the kernel that embed struct siginfo.

So split siginfo in two; kernel_siginfo and siginfo.  Keeping the
traditional name for the userspace definition.  While the version that
is used internally to the kernel and ultimately will not be padded to
128 bytes is called kernel_siginfo.

The definition of struct kernel_siginfo I have put in include/signal_types.h

A set of buildtime checks has been added to verify the two structures have
the same field offsets.

To make it easy to verify the change kernel_siginfo retains the same
size as siginfo.  The reduction in size comes in a following change.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-10-03 16:47:43 +02:00
..
compat.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
ipc_sysctl.c ipc/msg: increase MSGMNI, remove scaling 2014-12-13 12:42:52 -08:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
mq_sysctl.c ipc: convert use of typedef ctl_table to struct ctl_table 2014-06-06 16:08:16 -07:00
mqueue.c signal: Distinguish between kernel_siginfo and siginfo 2018-10-03 16:47:43 +02:00
msg.c ipc/util.c: further variable name cleanups 2018-08-22 10:52:52 -07:00
msgutil.c ipc: convert ipc_namespace.count from atomic_t to refcount_t 2017-09-08 18:26:51 -07:00
namespace.c ipc: simplify ipc initialization 2018-08-22 10:52:52 -07:00
sem.c ipc/util.c: further variable name cleanups 2018-08-22 10:52:52 -07:00
shm.c ipc/util.c: further variable name cleanups 2018-08-22 10:52:52 -07:00
syscall.c y2038: ipc: Redirect ipc(SEMTIMEDOP, ...) to compat_ksys_semtimedop 2018-04-20 16:20:30 +02:00
util.c ipc/util.c: update return value of ipc_getref from int to bool 2018-08-22 10:52:52 -07:00
util.h ipc/util.c: update return value of ipc_getref from int to bool 2018-08-22 10:52:52 -07:00