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<div dir="ltr">Maybe I miss something here.<br><pre>sd_err("failed to write object %"PRIx64", path=%s, <br>offset=%" PRId32 ", size=%"PRId32", result=%zd, %m", oid, path,<br> iocb->offset, iocb->length, size);<br><br>6 format positions with %, but only 5 values.<br>This looks a bug, and maybe the root cause why sd_err set errno?<br><br>Reset errno inside log_write will hide such errors if this is a <br>real bug.<br></pre>Roy<br><br><div>> Date: Wed, 4 Mar 2015 16:31:52 +0800<br>> From: namei.unix@gmail.com<br>> To: skypexu@gmail.com<br>> CC: sheepdog@lists.wpkg.org<br>> Subject: Re: [sheepdog] Unreliable error code handling in sheep/plainstore.c<br>> <br>> On Wed, Mar 04, 2015 at 04:21:46PM +0800, Xu Yifeng wrote:<br>> > I found some unreliable error handling in plainstore.c, reason is<br>> > combination of<br>> > sd_err() and err_to_sderr(), because it is not guaranteed that<br>> > sd_err() does not<br>> > muck errno, it is possible passing an mucked errno to<br>> > err_to_sderr(), see following<br>> > code in plain_store.c, line 758:<br>> > if (unlikely(size != len)) {<br>> > sd_err("failed to write object %"PRIx64", path=%s,<br>> > offset=%"<br>> > PRId32", size=%"PRId32", result=%zd, %m", oid, path,<br>> > iocb->offset, iocb->length, size);<br>> > ret = err_to_sderr(path, oid, errno);<br>> > goto out;<br>> > }<br>> > <br>> > it is possible that sd_err() may muck the errno, causing an<br>> > irrelevant errno to be passed to<br>> > err_to_sderr!<br>> <br>> Good catch!<br>> <br>> It is really a hidden bug for a long time. This might explain why I sometimes saw<br>> strange logs in the past!<br>> <br>> Could you please cook a decent patch for this problem? The fix looks good to me.<br>> <br>> Thanks,<br>> Yuan<br>> -- <br>> sheepdog mailing list<br>> sheepdog@lists.wpkg.org<br>> https://lists.wpkg.org/mailman/listinfo/sheepdog<br></div></div>
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