Bug 1914536
| Summary: | ftp: Binary file upload should stop upon socket write error. | ||||||
|---|---|---|---|---|---|---|---|
| Product: | Red Hat Enterprise Linux 7 | Reporter: | Tetsuo Handa <penguin-kernel> | ||||
| Component: | ftp | Assignee: | Michal Ruprich <mruprich> | ||||
| Status: | CLOSED WONTFIX | QA Contact: | rhel-cs-infra-services-qe <rhel-cs-infra-services-qe> | ||||
| Severity: | unspecified | Docs Contact: | |||||
| Priority: | unspecified | ||||||
| Version: | 7.9 | CC: | penguin-kernel | ||||
| Target Milestone: | rc | ||||||
| Target Release: | --- | ||||||
| Hardware: | Unspecified | ||||||
| OS: | Unspecified | ||||||
| Whiteboard: | |||||||
| Fixed In Version: | Doc Type: | If docs needed, set a value | |||||
| Doc Text: | Story Points: | --- | |||||
| Clone Of: | Environment: | ||||||
| Last Closed: | 2022-07-09 07:53:52 UTC | Type: | Bug | ||||
| Regression: | --- | Mount Type: | --- | ||||
| Documentation: | --- | CRM: | |||||
| Verified Versions: | Category: | --- | |||||
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |||||
| Cloudforms Team: | --- | Target Upstream Version: | |||||
| Embargoed: | |||||||
| Attachments: |
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Created attachment 1745845 [details]
Patch to fix this problem.
Hi Tetsuo, I can't reproduce this even when trying to forcefully cut off the network on the server side. If I shutdown an interface for a while, ftp can restore the connection afterwards and finish the operation. If I cut the connection with something like tcpkill, ftp ends with '426 Failure reading network stream.'. Do you remember which ftp server you used with this connection? Regards, Michal Thank you for taking the time to report this issue to us. We appreciate the feedback and use reports such as this one to guide our efforts at improving our products. That being said, this bug tracking system is not a mechanism for requesting support, and we are not able to guarantee the timeliness or suitability of a resolution.
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I reported this problem because I've heard that a RHEL user was experiencing partial lack of file data without error messages when uploading via ftp. Though I couldn't confirm if that user was actually hitting this problem. I don't think that cutting off the network on the server side is an appropriate fault injection for testing this problem, for the ftp server is irrelevant. I don't think that killing TCP connection is an appropriate fault injection for testing this problem, for killing TCP connection results in a PERMANENT error. I'm reporting that when this ftp client got a TEMPORARY write() failure, this ftp client is failing to abort (which causes partial lack of file data if subsequent write() succeeds). You can reproduce this problem using a fault injection patch in "Additional info:" which emulates a TEMPORARY write() failure. Then, please see the attached patch in comment 2. You will find that "while ((c = read(fileno(fin), buf, sizeof (buf))) > 0) { ... }" is failing to abort when write() in this loop got a TEMPORARY failure. After evaluating this issue, there are no plans to address it further or fix it in an upcoming release. Therefore, it is being closed. If plans change such that this issue will be fixed in an upcoming release, then the bug can be reopened. |
Description of problem: Binary file upload is unexpectedly continuing file read operation when socket write operation failed by a temporary error, due to "while() for() break;" trap. As a result, not only the server side receives a file which is smaller than the client side has, but also it makes impossible to resume binary file upload based on how far the server side has received. Version-Release number of selected component (if applicable): ftp-0.17-67.el7.x86_64 Additional info: I don't have a reproducer, but you can try this ftp client built with the following error injection patch applied. ---------- --- a/ftp/ftp.c +++ b/ftp/ftp.c @@ -722,9 +722,15 @@ errno = d = 0; while ((c = read(fileno(fin), buf, sizeof (buf))) > 0) { bytes += c; - for (bufp = buf; c > 0; c -= d, bufp += d) + for (bufp = buf; c > 0; c -= d, bufp += d) { + if (bytes == sizeof(buf) * 2) { + d = -1; + errno = ENOMEM; + break; + } if ((d = write(fileno(dout), bufp, c)) <= 0) break; + } if (hash) { while (bytes >= hashbytes) { /* <-- 'long long' signed overflow is */ (void) putchar('#'); /* possible. In this case, we can */ ----------