4.9-stable review patch. If anyone has any objections, please let me know.
------------------ From: Eric Biggers <[email protected]> commit 9903a91c763ecdae333a04a9d89d79d2b8966503 upstream. With pipe-user-pages-hard set to 'N', users were actually only allowed up to 'N - 1' buffers; and likewise for pipe-user-pages-soft. Fix this to allow up to 'N' buffers, as would be expected. Link: http://lkml.kernel.org/r/[email protected] Fixes: b0b91d18e2e9 ("pipe: fix limit checking in pipe_set_size()") Signed-off-by: Eric Biggers <[email protected]> Acked-by: Willy Tarreau <[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]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- fs/pipe.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/fs/pipe.c +++ b/fs/pipe.c @@ -609,12 +609,12 @@ static unsigned long account_pipe_buffer static bool too_many_pipe_buffers_soft(unsigned long user_bufs) { - return pipe_user_pages_soft && user_bufs >= pipe_user_pages_soft; + return pipe_user_pages_soft && user_bufs > pipe_user_pages_soft; } static bool too_many_pipe_buffers_hard(unsigned long user_bufs) { - return pipe_user_pages_hard && user_bufs >= pipe_user_pages_hard; + return pipe_user_pages_hard && user_bufs > pipe_user_pages_hard; } static bool is_unprivileged_user(void)
