diff options
| author | Michael Kerrisk (man-pages) <mtk.manpages@gmail.com> | 2016-10-11 13:53:25 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-10-11 15:06:31 -0700 |
| commit | d37d41666408102bf0ac8e48d8efdce7b809e5f6 (patch) | |
| tree | 89a771ab3ac640b7d9371cb922c9f1df14679e70 /fs | |
| parent | f491bd71118beba608d39ac2d5f1530e1160cd2e (diff) | |
pipe: move limit checking logic into pipe_set_size()
This is a preparatory patch for following work. Move the F_SETPIPE_SZ
limit-checking logic from pipe_fcntl() into pipe_set_size(). This
simplifies the code a little, and allows for reworking required in
a later patch that fixes the limit checking in pipe_set_size()
Link: http://lkml.kernel.org/r/3701b2c5-2c52-2c3e-226d-29b9deb29b50@gmail.com
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Reviewed-by: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Willy Tarreau <w@1wt.eu>
Cc: <socketpair@gmail.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Jens Axboe <axboe@fb.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/pipe.c | 41 |
1 files changed, 18 insertions, 23 deletions
diff --git a/fs/pipe.c b/fs/pipe.c index 8773ecaa44b5..a72b6ff9b48a 100644 --- a/fs/pipe.c +++ b/fs/pipe.c @@ -1023,9 +1023,24 @@ static inline unsigned int round_pipe_size(unsigned int size) * Allocate a new array of pipe buffers and copy the info over. Returns the * pipe size if successful, or return -ERROR on error. */ -static long pipe_set_size(struct pipe_inode_info *pipe, unsigned long nr_pages) +static long pipe_set_size(struct pipe_inode_info *pipe, unsigned long arg) { struct pipe_buffer *bufs; + unsigned int size, nr_pages; + + size = round_pipe_size(arg); + nr_pages = size >> PAGE_SHIFT; + + if (!nr_pages) + return -EINVAL; + + if (!capable(CAP_SYS_RESOURCE) && size > pipe_max_size) + return -EPERM; + + if ((too_many_pipe_buffers_hard(pipe->user) || + too_many_pipe_buffers_soft(pipe->user)) && + !capable(CAP_SYS_RESOURCE) && !capable(CAP_SYS_ADMIN)) + return -EPERM; /* * We can shrink the pipe, if arg >= pipe->nrbufs. Since we don't @@ -1109,28 +1124,9 @@ long pipe_fcntl(struct file *file, unsigned int cmd, unsigned long arg) __pipe_lock(pipe); switch (cmd) { - case F_SETPIPE_SZ: { - unsigned int size, nr_pages; - - size = round_pipe_size(arg); - nr_pages = size >> PAGE_SHIFT; - - ret = -EINVAL; - if (!nr_pages) - goto out; - - if (!capable(CAP_SYS_RESOURCE) && size > pipe_max_size) { - ret = -EPERM; - goto out; - } else if ((too_many_pipe_buffers_hard(pipe->user) || - too_many_pipe_buffers_soft(pipe->user)) && - !capable(CAP_SYS_RESOURCE) && !capable(CAP_SYS_ADMIN)) { - ret = -EPERM; - goto out; - } - ret = pipe_set_size(pipe, nr_pages); + case F_SETPIPE_SZ: + ret = pipe_set_size(pipe, arg); break; - } case F_GETPIPE_SZ: ret = pipe->buffers * PAGE_SIZE; break; @@ -1139,7 +1135,6 @@ long pipe_fcntl(struct file *file, unsigned int cmd, unsigned long arg) break; } -out: __pipe_unlock(pipe); return ret; } |