In the Linux kernel, the following vulnerability has been resolved: hsr: Prevent use after free in prp_create_tagged_frame() The prp_fill_rct() function can fail. In that situation, it frees the skb and returns NULL. Meanwhile on the success path, it returns the original skb. So it's straight forward to fix bug by using the returned value.
https://git.kernel.org/stable/c/ddf4e04e946aaa6c458b8b6829617cc44af2bffd
https://git.kernel.org/stable/c/d103fb6726904e353b4773188ee3d3acb4078363
https://git.kernel.org/stable/c/a1a485e45d24b1cd8fe834fd6f1b06e2903827da
https://git.kernel.org/stable/c/876f8ab52363f649bcc74072157dfd7adfbabc0d
https://git.kernel.org/stable/c/6086258bd5ea7b5c706ff62da42b8e271b2401db
https://git.kernel.org/stable/c/1787b9f0729d318d67cf7c5a95f0c3dba9a7cc18