LineageOS/android_packages_modules_Connectivity
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Don't leak map fds in BpfCoordinator#dump.

Browse Source 
Currently, the dump methods open BpfMap objects and never close
them. This leaks filedescriptors, and if dump is called often
enough, will crash the networkstack process.

Fix this by using try-with-resources statements that
automatically close the map when exiting the try block.

Change the signature of BpfMap#close from "throws Exception" to
"throws ErrnoException" since it does not throw any other type
of checked exceptions.

Test: "lsof | grep network_st" while running "dumpsys tethering bpf" in a loop
Change-Id: I66c407454c2715bf41bf3a2e81bd582f9ea5a905
This commit is contained in:
Lorenzo Colitti
2021-02-09 23:07:17 +09:00
parent 4431655a4d
commit 555472a186
2 changed files with 15 additions and 17 deletions
Download Patch File Download Diff File Expand all files Collapse all files

30
Tethering/src/com/android/networkstack/tethering/BpfCoordinator.java
View File

@@ -766,17 +766,16 @@ public class BpfCoordinator {
}
private void dumpIpv6UpstreamRules(IndentingPrintWriter pw) {
final BpfMap<TetherUpstream6Key, Tether6Value> ipv6UpstreamMap = mDeps.getBpfUpstream6Map();
if (ipv6UpstreamMap == null) {
pw.println("No IPv6 upstream");
return;
}
try {
if (ipv6UpstreamMap.isEmpty()) {
try (BpfMap<TetherUpstream6Key, Tether6Value> map = mDeps.getBpfUpstream6Map()) {
if (map == null) {
pw.println("No IPv6 upstream");
return;
}
if (map.isEmpty()) {
pw.println("No IPv6 upstream rules");
return;
}
ipv6UpstreamMap.forEach((k, v) -> pw.println(ipv6UpstreamRuletoString(k, v)));
map.forEach((k, v) -> pw.println(ipv6UpstreamRuletoString(k, v)));
} catch (ErrnoException e) {
pw.println("Error dumping IPv4 map: " + e);
}
@@ -797,19 +796,18 @@ public class BpfCoordinator {
}
private void dumpIpv4ForwardingRules(IndentingPrintWriter pw) {
final BpfMap<Tether4Key, Tether4Value> ipv4UpstreamMap = mDeps.getBpfUpstream4Map();
if (ipv4UpstreamMap == null) {
pw.println("No IPv4 support");
return;
}
try {
if (ipv4UpstreamMap.isEmpty()) {
try (BpfMap<Tether4Key, Tether4Value> map = mDeps.getBpfUpstream4Map()) {
if (map == null) {
pw.println("No IPv4 support");
return;
}
if (map.isEmpty()) {
pw.println("No IPv4 rules");
return;
}
pw.println("[IPv4]: iif(iface) oif(iface) src nat dst");
pw.increaseIndent();
ipv4UpstreamMap.forEach((k, v) -> pw.println(ipv4RuleToString(k, v)));
map.forEach((k, v) -> pw.println(ipv4RuleToString(k, v)));
} catch (ErrnoException e) {
pw.println("Error dumping IPv4 map: " + e);
}

2
Tethering/src/com/android/networkstack/tethering/BpfMap.java
View File

@@ -218,7 +218,7 @@ public class BpfMap<K extends Struct, V extends Struct> implements AutoCloseable
}
@Override
public void close() throws Exception {
public void close() throws ErrnoException {
closeMap(mMapFd);
}