nvmet-tcp: fix page fragment cache leak in error path

Summary

In the Linux kernel, the following vulnerability has been resolved: nvmet-tcp: fix page fragment cache leak in error path 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.

Timeline

1. Aug 15, 2026, 5:59 AM UTCCVE published
2. Oct 21, 2026, 12:45 PM UTCRecord last updated

Affected versions

• Linux Linux

  From 872d26a391da92ed8f0c0f5cb5fef428067b7f30 · fixed in fc11e3f0daaadb6e600a86e54b089d4662d0a464; From 872d26a391da92ed8f0c0f5cb5fef428067b7f30 · fixed in a43a9abc1ebf663f0aa56a729106f68dd9c77da6; From 872d26a391da92ed8f0c0f5cb5fef428067b7f30 · fixed in ba3209704b3cd46961e4e081af5c52a780785648; From 872d26a391da92ed8f0c0f5cb5fef428067b7f30 · fixed in 5fbe83a374f09561a0f0c1f4aa021501ffd681eb; From 872d26a391da92ed8f0c0f5cb5fef428067b7f30 · fixed in 4dae393956093c807212918fd91a8fc70df15338

• Linux Linux

  5.0

• KernelLinux

  From 5.0.0 · fixed in 6.6.160; From 6.7.0 · fixed in 6.12.97; From 6.13.0 · fixed in 6.18.40; From 6.19.0 · fixed in 7.1.5

References 5