Linus Torvalds f122a08b19 capability: just use a 'u64' instead of a 'u32[2]' array ... Back in 2008 we extended the capability bits from 32 to 64, and we did it by extending the single 32-bit capability word from one word to an array of two words. It was then obfuscated by hiding the "2" behind two macro expansions, with the reasoning being that maybe it gets extended further some day. That reasoning may have been valid at the time, but the last thing we want to do is to extend the capability set any more. And the array of values not only causes source code oddities (with loops to deal with it), but also results in worse code generation. It's a lose-lose situation. So just change the 'u32[2]' into a 'u64' and be done with it. We still have to deal with the fact that the user space interface is designed around an array of these 32-bit values, but that was the case before too, since the array layouts were different (ie user space doesn't use an array of 32-bit values for individual capability masks, but an array of 32-bit slices of multiple masks). So that marshalling of data is actually simplified too, even if it does remain somewhat obscure and odd. This was all triggered by my reaction to the new "cap_isidentical()" introduced recently. By just using a saner data structure, it went from unsigned __capi; CAP_FOR_EACH_U32(__capi) { if (a.cap[__capi] != b.cap[__capi]) return false; } return true; to just being return a.val == b.val; instead. Which is rather more obvious both to humans and to compilers. Cc: Mateusz Guzik <mjguzik@gmail.com> Cc: Casey Schaufler <casey@schaufler-ca.com> Cc: Serge Hallyn <serge@hallyn.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Paul Moore <paul@paul-moore.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2023-03-01 10:01:22 -08:00
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apparmor	capability: just use a 'u64' instead of a 'u32[2]' array	2023-03-01 10:01:22 -08:00
bpf
integrity
keys
landlock
loadpin
lockdown
safesetid
selinux
smack
tomoyo
yama
commoncap.c	capability: just use a 'u64' instead of a 'u32[2]' array	2023-03-01 10:01:22 -08:00
device_cgroup.c
inode.c
Kconfig
Kconfig.hardening
lsm_audit.c
Makefile
min_addr.c
security.c