pipe: actually allow root to exceed the pipe buffer limits

pipe-user-pages-hard and pipe-user-pages-soft are only supposed to apply
to unprivileged users, as documented in both Documentation/sysctl/fs.txt
and the pipe(7) man page.

However, the capabilities are actually only checked when increasing a
pipe's size using F_SETPIPE_SZ, not when creating a new pipe.  Therefore,
if pipe-user-pages-hard has been set, the root user can run into it and be
unable to create pipes.  Similarly, if pipe-user-pages-soft has been set,
the root user can run into it and have their pipes limited to 1 page each.

Fix this by allowing the privileged override in both cases.

Link: http://lkml.kernel.org/r/[email protected]
Fixes: 759c01142a5d ("pipe: limit the per-user amount of pages allocated in pipes")
Signed-off-by: Eric Biggers <[email protected]>
Acked-by: Kees Cook <[email protected]>
Acked-by: Joe Lawrence <[email protected]>
Cc: Alexander Viro <[email protected]>
Cc: "Luis R . Rodriguez" <[email protected]>
Cc: Michael Kerrisk <[email protected]>
Cc: Mikulas Patocka <[email protected]>
Cc: Willy Tarreau <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

0 files changed, 0 insertions, 0 deletions