From: Al Viro Date: Tue, 12 Mar 2013 02:59:49 +0000 (+0000) Subject: vfs: fix pipe counter breakage X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=a930d8790552658140d7d0d2e316af4f0d76a512;p=openwrt%2Fstaging%2Fblogic.git vfs: fix pipe counter breakage If you open a pipe for neither read nor write, the pipe code will not add any usage counters to the pipe, causing the 'struct pipe_inode_info" to be potentially released early. That doesn't normally matter, since you cannot actually use the pipe, but the pipe release code - particularly fasync handling - still expects the actual pipe infrastructure to all be there. And rather than adding NULL pointer checks, let's just disallow this case, the same way we already do for the named pipe ("fifo") case. This is ancient going back to pre-2.4 days, and until trinity, nobody naver noticed. Reported-by: Dave Jones Signed-off-by: Linus Torvalds --- diff --git a/fs/pipe.c b/fs/pipe.c index 64a494cef0a0..2234f3f61f8d 100644 --- a/fs/pipe.c +++ b/fs/pipe.c @@ -863,6 +863,9 @@ pipe_rdwr_open(struct inode *inode, struct file *filp) { int ret = -ENOENT; + if (!(filp->f_mode & (FMODE_READ|FMODE_WRITE))) + return -EINVAL; + mutex_lock(&inode->i_mutex); if (inode->i_pipe) {