6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Geliang Tang [ Upstream commit 4dae393956093c807212918fd91a8fc70df15338 ] In nvmet_tcp_alloc_queue(), when a connection is closed during the allocation process (e.g., nvmet_tcp_set_queue_sock() returns -ENOTCONN), the error handling jumps to out_destroy_sq and then to out_ida_remove without draining the page fragment cache. Although nvmet_tcp_free_cmd() is called in some error paths to release individual page fragments, the underlying page cache reference held by queue->pf_cache is never released. The first allocation using pf_cache is the call to nvmet_tcp_alloc_cmd() for queue->connect, which happens after ida_alloc() returns successfully. This results in a page leak each time a connection fails during allocation, which could lead to memory exhaustion over time if connections are repeatedly opened and closed. Fix this by calling page_frag_cache_drain() before freeing the queue structure in the out_ida_remove label. Fixes: 872d26a391da ("nvmet-tcp: add NVMe over TCP target driver") Reviewed-by: Christoph Hellwig Signed-off-by: Geliang Tang Signed-off-by: Keith Busch Signed-off-by: Sasha Levin --- drivers/nvme/target/tcp.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/nvme/target/tcp.c b/drivers/nvme/target/tcp.c index e2d1f2e6012a7..52a435499f9cb 100644 --- a/drivers/nvme/target/tcp.c +++ b/drivers/nvme/target/tcp.c @@ -1792,6 +1792,12 @@ static void nvmet_tcp_alloc_queue(struct nvmet_tcp_port *port, nvmet_tcp_free_cmd(&queue->connect); out_ida_remove: ida_free(&nvmet_tcp_queue_ida, queue->idx); + /* + * Drain the page fragment cache if any allocations were done. + * The first allocation using pf_cache is nvmet_tcp_alloc_cmd() + * for queue->connect after ida_alloc(). + */ + page_frag_cache_drain(&queue->pf_cache); out_sock: fput(queue->sock->file); out_free_queue: -- 2.53.0