diff options
author | Eric Biggers <ebiggers@google.com> | 2018-02-07 00:41:56 +0100 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-02-07 03:32:47 +0100 |
commit | 9903a91c763ecdae333a04a9d89d79d2b8966503 (patch) | |
tree | 62181e45190b53365475094bc2dd66ec9ad415b4 /fs/pipe.c | |
parent | pipe: actually allow root to exceed the pipe buffer limits (diff) | |
download | linux-9903a91c763ecdae333a04a9d89d79d2b8966503.tar.xz linux-9903a91c763ecdae333a04a9d89d79d2b8966503.zip |
pipe: fix off-by-one error when checking buffer limits
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/20180111052902.14409-5-ebiggers3@gmail.com
Fixes: b0b91d18e2e9 ("pipe: fix limit checking in pipe_set_size()")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Willy Tarreau <w@1wt.eu>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: "Luis R . Rodriguez" <mcgrof@kernel.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to '')
-rw-r--r-- | fs/pipe.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/fs/pipe.c b/fs/pipe.c index 04acfad4692b..46c30ac777da 100644 --- a/fs/pipe.c +++ b/fs/pipe.c @@ -605,12 +605,12 @@ static unsigned long account_pipe_buffers(struct user_struct *user, 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) |