[
https://issues.apache.org/jira/browse/HBASE-30340?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Sercan Tekin updated HBASE-30340:
---------------------------------
Description:
{{CatalogJanitor.scan()}} can allow concurrent scans due to incorrect handling
of the
{{alreadyRunning}} lock.
Currently, the lock acquisition is performed inside the {{try}} block:
{code:java}
try {
if (!alreadyRunning.compareAndSet(false, true)) {
return -1;
}
...
} finally {
alreadyRunning.set(false);
}
{code}
When a scan is already running, a concurrent scan fails the {{compareAndSet()}}
and
returns immediately. However, because the lock acquisition is inside the
{{try}} block,
the {{finally}} block is still executed and resets {{alreadyRunning}} to false.
This allows another scan to acquire the lock while the original scan is still
running.
The lock acquisition should be moved before the {{try}} block:
{code:java}
if (!alreadyRunning.compareAndSet(false, true)) {
return -1;
}
try {
...
} finally {
alreadyRunning.set(false);
}
{code}
This prevents another scan from starting until the current scan has completed.
was:
`CatalogJanitor.scan()` can allow concurrent scans due to incorrect handling of
the
`alreadyRunning` lock.
Currently, the lock acquisition is performed inside the `try` block:
try {
if (!alreadyRunning.compareAndSet(false, true)) {
return -1;
}
...
} finally {
alreadyRunning.set(false);
}
When a scan is already running, a concurrent scan fails the `compareAndSet()`
and
returns immediately. However, because the lock acquisition is inside the `try`
block,
the `finally` block is still executed and resets `alreadyRunning` to false.
This allows another scan to acquire the lock while the original scan is still
running.
The lock acquisition should be moved before the `try` block:
if (!alreadyRunning.compareAndSet(false, true)) {
return -1;
}
try {
...
} finally {
alreadyRunning.set(false);
}
This prevents another scan from starting until the current scan has completed.
> CatalogJanitor can run concurrent scans due to incorrect alreadyRunning lock
> handling
> -------------------------------------------------------------------------------------
>
> Key: HBASE-30340
> URL: https://issues.apache.org/jira/browse/HBASE-30340
> Project: HBase
> Issue Type: Bug
> Components: master
> Affects Versions: 0.90.5
> Reporter: Sercan Tekin
> Priority: Critical
>
> {{CatalogJanitor.scan()}} can allow concurrent scans due to incorrect
> handling of the
> {{alreadyRunning}} lock.
> Currently, the lock acquisition is performed inside the {{try}} block:
> {code:java}
> try {
> if (!alreadyRunning.compareAndSet(false, true)) {
> return -1;
> }
> ...
> } finally {
> alreadyRunning.set(false);
> }
> {code}
> When a scan is already running, a concurrent scan fails the
> {{compareAndSet()}} and
> returns immediately. However, because the lock acquisition is inside the
> {{try}} block,
> the {{finally}} block is still executed and resets {{alreadyRunning}} to
> false.
> This allows another scan to acquire the lock while the original scan is still
> running.
> The lock acquisition should be moved before the {{try}} block:
> {code:java}
> if (!alreadyRunning.compareAndSet(false, true)) {
> return -1;
> }
> try {
> ...
> } finally {
> alreadyRunning.set(false);
> }
> {code}
> This prevents another scan from starting until the current scan has completed.
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
