6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
commit 0d459e2ffb541841714839e8228b845458ed3b27 upstream.
The commit mutex should not be released during the critical section
between nft_gc_seq_begin() and nft_gc_seq_end(), otherwise, async GC
worker could collect expired objects and get the released commit lock
within the same GC sequence.
nf_tables_module_autoload() temporarily releases the mutex to load
module dependencies, then it goes back to replay the transaction again.
Move it at the end of the abort phase after nft_gc_seq_end() is called.
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 720344340fb9 ("netfilter: nf_tables: GC transaction race with abort path")
Reported-by: Kuan-Ting Chen <hexrabbit@xxxxxxxx>
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/netfilter/nf_tables_api.c | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -10518,11 +10518,6 @@ static int __nf_tables_abort(struct net
nf_tables_abort_release(trans);
}
- if (action == NFNL_ABORT_AUTOLOAD)
- nf_tables_module_autoload(net);
- else
- nf_tables_module_autoload_cleanup(net);
-
return err;
}
@@ -10539,6 +10534,14 @@ static int nf_tables_abort(struct net *n
WARN_ON_ONCE(!list_empty(&nft_net->commit_list));
+ /* module autoload needs to happen after GC sequence update because it
+ * temporarily releases and grabs mutex again.
+ */
+ if (action == NFNL_ABORT_AUTOLOAD)
+ nf_tables_module_autoload(net);
+ else
+ nf_tables_module_autoload_cleanup(net);
+
mutex_unlock(&nft_net->commit_mutex);
return ret;
