In the Linux kernel, the following vulnerability has been resolved:

net: sched: fix memory leak in tcindex_partial_destroy_work

Syzbot reported memory leak in tcindex_set_parms(). The problem was in
non-freed perfect hash in tcindex_partial_destroy_work().

In tcindex_set_parms() new tcindex_data is allocated and some fields from
old one are copied to new one, but not the perfect hash. Since
tcindex_partial_destroy_work() is the destroy function for old
tcindex_data, we need to free perfect hash to avoid memory leak.

References

• https://nvd.nist.gov/vuln/detail/CVE-2021-47295
• https://git.kernel.org/stable/c/8d7924ce85bae64e7a67c366c7c50840f49f3a62
• https://git.kernel.org/stable/c/8e9662fde6d63c78eb1350f6167f64c9d71a865b
• https://git.kernel.org/stable/c/cac71d27745f92ee13f0ecc668ffe151a4a9c9b1
• https://git.kernel.org/stable/c/f5051bcece50140abd1a11a2d36dc3ec5484fc32