| Message ID | 20241107-mptcp-pm-lookup_addr_rcu-v3-1-3c458d025de4@kernel.org (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Commit | 562b779666e294894056d756385b051ed38b0af9 |
| Delegated to: | Matthieu Baerts |
| Headers | show |
| Series | mptcp: pm: use _rcu variant under rcu_read_lock | expand |
| Context | Check | Description |
|---|---|---|
| matttbe/build | success | Build and static analysis OK |
| matttbe/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 9 lines checked |
| matttbe/shellcheck | success | MPTCP selftests files have not been modified |
| matttbe/KVM_Validation__normal | success | Success! ✅ |
| matttbe/KVM_Validation__debug | success | Success! ✅ |
| matttbe/KVM_Validation__btf-normal__only_bpftest_all_ | success | Success! ✅ |
| matttbe/KVM_Validation__btf-debug__only_bpftest_all_ | success | Success! ✅ |
diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c index 618289aac0ab7f558d55d8b2ebb00dc62fc72f88..758a0dbfcf78e545d840c0b580c0b12bd042d7a4 100644 --- a/net/mptcp/pm_netlink.c +++ b/net/mptcp/pm_netlink.c @@ -524,7 +524,8 @@ __lookup_addr(struct pm_nl_pernet *pernet, const struct mptcp_addr_info *info) { struct mptcp_pm_addr_entry *entry; - list_for_each_entry(entry, &pernet->local_addr_list, list) { + list_for_each_entry_rcu(entry, &pernet->local_addr_list, list, + lockdep_is_held(&pernet->lock)) { if (mptcp_addresses_equal(&entry->addr, info, entry->addr.port)) return entry; }
In mptcp_pm_create_subflow_or_signal_addr(), rcu_read_(un)lock() are used as expected to iterate over the list of local addresses, but list_for_each_entry() was used instead of list_for_each_entry_rcu() in __lookup_addr(). It is important to use this variant which adds the required READ_ONCE() (and diagnostic checks if enabled). Because __lookup_addr() is also used in mptcp_pm_nl_set_flags() where it is called under the pernet->lock and not rcu_read_lock(), an extra condition is then passed to help the diagnostic checks making sure either the associated spin lock or the RCU lock is held. Fixes: 86e39e04482b ("mptcp: keep track of local endpoint still available for each msk") Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> --- v3: - Use list_for_each_entry_rcu() with lockdep_is_held(). - Update commit message accordingly. --- net/mptcp/pm_netlink.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)