diff options
| author | Tom Lane <tgl@sss.pgh.pa.us> | 2020-07-21 11:40:47 -0400 |
|---|---|---|
| committer | Tom Lane <tgl@sss.pgh.pa.us> | 2020-07-21 11:40:47 -0400 |
| commit | ae3d40b0cdc6bff33ad3caf5e8766b85ebe24168 (patch) | |
| tree | 6ebb4642f27cda17340a06e587acc89c4a01ca36 /doc/src | |
| parent | 39d6aec1927cc87942feb4b021360605f0a4ce8a (diff) | |
Avoid direct C access to possibly-null pg_subscription_rel.srsublsn.
This coding technique is unsafe, since we'd be accessing off the end
of the tuple if the field is null. SIGSEGV is pretty improbable, but
perhaps not impossible. Also, returning garbage for the LSN doesn't
seem like a great idea, even if callers aren't looking at it today.
Also update docs to point out explicitly that
pg_subscription.subslotname and pg_subscription_rel.srsublsn
can be null.
Perhaps we should mark these two fields BKI_FORCE_NULL, so that
they'd be correctly labeled in databases that are initdb'd in the
future. But we can't force that for existing databases, and on
balance it's not too clear that having a mix of different catalog
contents in the field would be wise.
Apply to v10 (where this code came in) through v12. Already
fixed in v13 and HEAD.
Discussion: https://postgr.es/m/732838.1595278439@sss.pgh.pa.us
Diffstat (limited to 'doc/src')
| -rw-r--r-- | doc/src/sgml/catalogs.sgml | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/doc/src/sgml/catalogs.sgml b/doc/src/sgml/catalogs.sgml index 9f2273b5833..f314f93051d 100644 --- a/doc/src/sgml/catalogs.sgml +++ b/doc/src/sgml/catalogs.sgml @@ -6578,8 +6578,9 @@ SCRAM-SHA-256$<replaceable><iteration count></>:<replaceable><salt>< <entry><structfield>subslotname</structfield></entry> <entry><type>name</type></entry> <entry></entry> - <entry>Name of the replication slot in the upstream database. Also used - for local replication origin name.</entry> + <entry>Name of the replication slot in the upstream database (also used + for the local replication origin name); + null represents <literal>NONE</literal></entry> </row> <row> @@ -6661,7 +6662,9 @@ SCRAM-SHA-256$<replaceable><iteration count></>:<replaceable><salt>< <entry><type>pg_lsn</type></entry> <entry></entry> <entry> - End LSN for <literal>s</> and <literal>r</> states. + Remote LSN of the state change used for synchronization coordination + when in <literal>s</literal> or <literal>r</literal> states, + otherwise null </entry> </row> </tbody> |