Commit Graph

3 Commits

Author SHA1 Message Date
Qian Cai
5e5412c365 net/socket: fix GCC8+ Wpacked-not-aligned warnings
There are a lot of those warnings with GCC8+ 64-bit,

In file included from ./include/linux/sctp.h:42,
                 from net/core/skbuff.c:47:
./include/uapi/linux/sctp.h:395:1: warning: alignment 4 of 'struct
sctp_paddr_change' is less than 8 [-Wpacked-not-aligned]
 } __attribute__((packed, aligned(4)));
 ^
./include/uapi/linux/sctp.h:728:1: warning: alignment 4 of 'struct
sctp_setpeerprim' is less than 8 [-Wpacked-not-aligned]
 } __attribute__((packed, aligned(4)));
 ^
./include/uapi/linux/sctp.h:727:26: warning: 'sspp_addr' offset 4 in
'struct sctp_setpeerprim' isn't aligned to 8 [-Wpacked-not-aligned]
  struct sockaddr_storage sspp_addr;
                          ^~~~~~~~~
./include/uapi/linux/sctp.h:741:1: warning: alignment 4 of 'struct
sctp_prim' is less than 8 [-Wpacked-not-aligned]
 } __attribute__((packed, aligned(4)));
 ^
./include/uapi/linux/sctp.h:740:26: warning: 'ssp_addr' offset 4 in
'struct sctp_prim' isn't aligned to 8 [-Wpacked-not-aligned]
  struct sockaddr_storage ssp_addr;
                          ^~~~~~~~
./include/uapi/linux/sctp.h:792:1: warning: alignment 4 of 'struct
sctp_paddrparams' is less than 8 [-Wpacked-not-aligned]
 } __attribute__((packed, aligned(4)));
 ^
./include/uapi/linux/sctp.h:784:26: warning: 'spp_address' offset 4 in
'struct sctp_paddrparams' isn't aligned to 8 [-Wpacked-not-aligned]
  struct sockaddr_storage spp_address;
                          ^~~~~~~~~~~
./include/uapi/linux/sctp.h:905:1: warning: alignment 4 of 'struct
sctp_paddrinfo' is less than 8 [-Wpacked-not-aligned]
 } __attribute__((packed, aligned(4)));
 ^
./include/uapi/linux/sctp.h:899:26: warning: 'spinfo_address' offset 4
in 'struct sctp_paddrinfo' isn't aligned to 8 [-Wpacked-not-aligned]
  struct sockaddr_storage spinfo_address;
                          ^~~~~~~~~~~~~~

This is because the commit 20c9c825b1 ("[SCTP] Fix SCTP socket options
to work with 32-bit apps on 64-bit kernels.") added "packed, aligned(4)"
GCC attributes to some structures but one of the members, i.e, "struct
sockaddr_storage" in those structures has the attribute,
"aligned(__alignof__ (struct sockaddr *)" which is 8-byte on 64-bit
systems, so the commit overwrites the designed alignments for
"sockaddr_storage".

To fix this, "struct sockaddr_storage" needs to be aligned to 4-byte as
it is only used in those packed sctp structure which is part of UAPI,
and "struct __kernel_sockaddr_storage" is used in some other
places of UAPI that need not to change alignments in order to not
breaking userspace.

Use an implicit alignment for "struct __kernel_sockaddr_storage" so it
can keep the same alignments as a member in both packed and un-packed
structures without breaking UAPI.

Suggested-by: David Laight <David.Laight@ACULAB.COM>
Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-03 11:02:46 -07:00
Greg Kroah-Hartman
6f52b16c5b License cleanup: add SPDX license identifier to uapi header files with no license
Many user space API headers are missing licensing information, which
makes it hard for compliance tools to determine the correct license.

By default are files without license information under the default
license of the kernel, which is GPLV2.  Marking them GPLV2 would exclude
them from being included in non GPLV2 code, which is obviously not
intended. The user space API headers fall under the syscall exception
which is in the kernels COPYING file:

   NOTE! This copyright does *not* cover user programs that use kernel
   services by normal system calls - this is merely considered normal use
   of the kernel, and does *not* fall under the heading of "derived work".

otherwise syscall usage would not be possible.

Update the files which contain no license information with an SPDX
license identifier.  The chosen identifier is 'GPL-2.0 WITH
Linux-syscall-note' which is the officially assigned identifier for the
Linux syscall exception.  SPDX license identifiers are a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.  See the previous patch in this series for the
methodology of how this patch was researched.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:19:54 +01:00
David Howells
607ca46e97 UAPI: (Scripted) Disintegrate include/linux
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Michael Kerrisk <mtk.manpages@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Dave Jones <davej@redhat.com>
2012-10-13 10:46:48 +01:00