gvsafronov/futriix
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Prevent replicas from sending commands that interact with keyspace (#8868)

Browse Source 
This solves an issue reported in #8712 in which a replica would bypass
the client write pause check and cause an assertion due to executing a
write command during failover.

The fact is that we don't expect replicas to execute any command other
than maybe REPLCONF and PING, etc. but matching against the ADMIN
command flag is insufficient, so instead i just block keyspace access
for now.

(cherry picked from commit 46f4ebbe842620f0976a36741a72482620aa4b48)
This commit is contained in:
Oran Agra 2021-04-27 08:15:10 +03:00
parent 9d71ac0a6e
commit 91c450e80a
1 changed files with 11 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
src/server.c
View File

@ -3985,6 +3985,8 @@ int processCommand(client *c) {
return C_OK;
}
int is_read_command = (c->cmd->flags & CMD_READONLY) ||
(c->cmd->proc == execCommand && (c->mstate.cmd_flags & CMD_READONLY));
int is_write_command = (c->cmd->flags & CMD_WRITE) ||
(c->cmd->proc == execCommand && (c->mstate.cmd_flags & CMD_WRITE));
int is_denyoom_command = (c->cmd->flags & CMD_DENYOOM) ||
@ -4194,7 +4196,7 @@ int processCommand(client *c) {
c->cmd->proc != discardCommand &&
c->cmd->proc != watchCommand &&
c->cmd->proc != unwatchCommand &&
c->cmd->proc != resetCommand &&
c->cmd->proc != resetCommand &&
!(c->cmd->proc == shutdownCommand &&
c->argc == 2 &&
tolower(((char*)c->argv[1]->ptr)[0]) == 'n') &&
@ -4206,6 +4208,14 @@ int processCommand(client *c) {
return C_OK;
}
/* Prevent a replica from sending commands that access the keyspace.
* The main objective here is to prevent abuse of client pause check
* from which replicas are exempt. */
if ((c->flags & CLIENT_SLAVE) && (is_may_replicate_command || is_write_command || is_read_command)) {
rejectCommandFormat(c, "Replica can't interract with the keyspace");
return C_OK;
}
/* If the server is paused, block the client until
* the pause has ended. Replicas are never paused. */
if (!(c->flags & CLIENT_SLAVE) &&