linux/security
Arnd Bergmann 8aa7285682 security: commoncap: fix -Wstringop-overread warning
commit 82e5d8cc768b0c7b03c551a9ab1f8f3f68d5f83f upstream.

gcc-11 introdces a harmless warning for cap_inode_getsecurity:

security/commoncap.c: In function ‘cap_inode_getsecurity’:
security/commoncap.c:440:33: error: ‘memcpy’ reading 16 bytes from a region of size 0 [-Werror=stringop-overread]
  440 |                                 memcpy(&nscap->data, &cap->data, sizeof(__le32) * 2 * VFS_CAP_U32);
      |                                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The problem here is that tmpbuf is initialized to NULL, so gcc assumes
it is not accessible unless it gets set by vfs_getxattr_alloc().  This is
a legitimate warning as far as I can tell, but the code is correct since
it correctly handles the error when that function fails.

Add a separate NULL check to tell gcc about it as well.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: James Morris <jamorris@linux.microsoft.com>
Cc: Andrey Zhizhikin <andrey.z@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-11 14:04:16 +02:00
..
apparmor
integrity
keys
loadpin
lockdown
safesetid
selinux
smack
tomoyo
yama
Kconfig
Kconfig.hardening
Makefile
commoncap.c security: commoncap: fix -Wstringop-overread warning 2021-05-11 14:04:16 +02:00
device_cgroup.c
inode.c
lsm_audit.c
min_addr.c
security.c