CVE-2025-37915

Summary

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

net_sched: drr: Fix double list add in class with netem as child qdisc

As described in Gerrard's report [1], there are use cases where a netem child qdisc will make the parent qdisc's enqueue callback reentrant. In the case of drr, there won't be a UAF, but the code will add the same classifier to the list twice, which will cause memory corruption.

In addition to checking for qlen being zero, this patch checks whether the class was already added to the active_list (cl_is_active) before adding to the list to cover for the reentrant case.

[1] https://lore.kernel.org/netdev/CAHcdcOm+03OD2j6R0=YHKqmy=VgJ8xEOKuP6c7mSgnp-TEJJbw@mail.gmail.com/

Affected Software

VendorProductVersion RangeStatus
LinuxLinux37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea < 5da3aad1a13e7edb8ff0778a444ccf49930313e9affected
LinuxLinux37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea < 4b07ac06b0a712923255aaf2691637693fc7100daffected
LinuxLinux37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea < 2968632880f1792007eedd12eeedf7f6e2b7e9f3affected
LinuxLinux37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea < 4f0ecf50cdf76da95828578a92f130b653ac2fcfaffected
LinuxLinux37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea < db205b92dfe0501e5b92fb7cf00971d0e44ba3ebaffected
LinuxLinux37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea < 26e75716b94d6ff9be5ea07d63675c4d189f30b4affected
LinuxLinux37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea < ab2248110738d4429668140ad22f530a9ee730e1affected
LinuxLinux37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea < f99a3fbf023e20b626be4b0f042463d598050c9aaffected
LinuxLinux5.0affected
LinuxLinux0 < 5.0unaffected
LinuxLinux5.4.294 <= 5.4.*unaffected
LinuxLinux5.10.238 <= 5.10.*unaffected
LinuxLinux5.15.182 <= 5.15.*unaffected
LinuxLinux6.1.138 <= 6.1.*unaffected
LinuxLinux6.6.90 <= 6.6.*unaffected
LinuxLinux6.12.28 <= 6.12.*unaffected
LinuxLinux6.14.6 <= 6.14.*unaffected
LinuxLinux6.15 <= *unaffected

Weaknesses

ADP Enrichment

CVE Program Container

Additional References

References