forked from Minki/linux
splice: fix infinite loop in generic_file_splice_read()
There's a quirky loop in generic_file_splice_read() that could go on indefinitely, if the file splice returns 0 permanently (and not just as a temporary condition). Get rid of the loop and pass back -EAGAIN correctly from __generic_file_splice_read(), so we handle that condition properly as well. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
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parent
f4be31ec96
commit
8191ecd1d1
31
fs/splice.c
31
fs/splice.c
@ -370,8 +370,10 @@ __generic_file_splice_read(struct file *in, loff_t *ppos,
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* for an in-flight io page
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*/
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if (flags & SPLICE_F_NONBLOCK) {
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if (TestSetPageLocked(page))
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if (TestSetPageLocked(page)) {
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error = -EAGAIN;
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break;
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}
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} else
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lock_page(page);
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@ -479,9 +481,8 @@ ssize_t generic_file_splice_read(struct file *in, loff_t *ppos,
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struct pipe_inode_info *pipe, size_t len,
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unsigned int flags)
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{
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ssize_t spliced;
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int ret;
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loff_t isize, left;
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int ret;
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isize = i_size_read(in->f_mapping->host);
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if (unlikely(*ppos >= isize))
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@ -491,29 +492,9 @@ ssize_t generic_file_splice_read(struct file *in, loff_t *ppos,
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if (unlikely(left < len))
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len = left;
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ret = 0;
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spliced = 0;
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while (len && !spliced) {
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ret = __generic_file_splice_read(in, ppos, pipe, len, flags);
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if (ret < 0)
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break;
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else if (!ret) {
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if (spliced)
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break;
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if (flags & SPLICE_F_NONBLOCK) {
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ret = -EAGAIN;
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break;
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}
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}
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ret = __generic_file_splice_read(in, ppos, pipe, len, flags);
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if (ret > 0)
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*ppos += ret;
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len -= ret;
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spliced += ret;
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}
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if (spliced)
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return spliced;
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return ret;
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}
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