Description
In the Linux kernel, the following vulnerability has been resolved: net: airoha: Fix use-after-free in metadata dst teardown airoha_metadata_dst_free() runs metadata_dst_free() which frees the metadata_dst with kfree() immediately, bypassing the RCU grace period. In the RX path, skb_dst_set_noref() sets a non-refcounted pointer from the skb to the metadata_dst. This function requires RCU read-side protection and the dst must remain valid until all RCU readers complete. Since metadata_dst_free() calls kfree() directly, an use-after-free can occur if any skb still holds a noref pointer to the dst when the driver tears it down. Replace metadata_dst_free() with dst_release() which properly goes through the refcount path: when the refcount drops to zero, it schedules the actual free via call_rcu_hurry(), ensuring all RCU readers have completed before the memory is freed.
CVSS breakdown
Affected products
- Linux / Linuxaf3cf757d5c99011b9b94ea8d78aeaccc0153fdc – 6f829e2c17a53a35321268339cd252aff6d6d723
- Linux / Linuxaf3cf757d5c99011b9b94ea8d78aeaccc0153fdc – 4b5a574e033e66d2131eff1c18feef8d8643c67e
- Linux / Linuxaf3cf757d5c99011b9b94ea8d78aeaccc0153fdc – b38cae85d1c45ff189d7ecb6ac36f41cdc3d84d0
- Linux / Linux6.15 – 6.15
- Linux / Linux0 – 6.15
- Linux / Linux6.18.36 – 6.18.*
- Linux / Linux7.0.13 – 7.0.*
- Linux / Linux7.1 – *