[SERVER-63193] Watchdog may return success reading from page cache Created: 01/Feb/22 Updated: 29/Oct/23 Resolved: 04/Aug/22 |
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| Status: | Closed |
| Project: | Core Server |
| Component/s: | None |
| Affects Version/s: | 5.2.0 |
| Fix Version/s: | 6.1.0-rc0 |
| Type: | Bug | Priority: | Major - P3 |
| Reporter: | Kevin Arhelger | Assignee: | Gabriel Marks |
| Resolution: | Fixed | Votes: | 0 |
| Labels: | None | ||
| Remaining Estimate: | Not Specified | ||
| Time Spent: | Not Specified | ||
| Original Estimate: | Not Specified | ||
| Environment: |
Linux |
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| Issue Links: |
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| Backwards Compatibility: | Fully Compatible | ||||
| Operating System: | ALL | ||||
| Sprint: | Security 2022-05-02, Security 2022-05-16, Security 2022-05-30, Security 2022-07-11, Security 2022-07-25, Security 2022-08-08 | ||||
| Participants: | |||||
| Case: | (copied to CRM) | ||||
| Linked BF Score: | 35 | ||||
| Description |
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The comment on checkFile states this is “open a direct_io” to a new file. However, the O_DIRECT flag is not added to the open call. This should mean this is a standard, buffered IO. https://github.com/mongodb/mongo/blob/master/src/mongo/watchdog/watchdog.cpp#L467 In an asymmetric storage failure where writes can complete, but reads are blocked, the read at https://github.com/mongodb/mongo/blob/master/src/mongo/watchdog/watchdog.cpp#L522 could be serviced from the Linux page cache, erroneously returning a success. |
| Comments |
| Comment by Githook User [ 25/Jul/22 ] |
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Author: {'name': 'Gabriel Marks', 'email': 'gabriel.marks@mongodb.com', 'username': 'marksg07'}Message: Revert " This reverts commit 50d4bcf42c06c70d179c128247919e62d5bffa50. |
| Comment by Githook User [ 25/Jul/22 ] |
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Author: {'name': 'Gabriel Marks', 'email': 'gabriel.marks@mongodb.com', 'username': 'marksg07'}Message: |