{"cve":"CVE-2022-49808","nvd":{"published":"2025-05-01T15:16:04.130","modified":"2026-06-17T05:19:11.760","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: dsa: don't leak tagger-owned storage on switch driver unbind\n\nIn the initial commit dc452a471dba (\"net: dsa: introduce tagger-owned\nstorage for private and shared data\"), we had a call to\ntag_ops->disconnect(dst) issued from dsa_tree_free(), which is called at\ntree teardown time.\n\nThere were problems with connecting to a switch tree as a whole, so this\ngot reworked to connecting to individual switches within the tree. In\nthis process, tag_ops->disconnect(ds) was made to be called only from\nswitch.c (cross-chip notifiers emitted as a result of dynamic tag proto\nchanges), but the normal driver teardown code path wasn't replaced with\nanything.\n\nSolve this problem by adding a function that does the opposite of\ndsa_switch_setup_tag_protocol(), which is called from the equivalent\nspot in dsa_switch_teardown(). The positioning here also ensures that we\nwon't have any use-after-free in tagging protocol (*rcv) ops, since the\nteardown sequence is as follows:\n\ndsa_tree_teardown\n-> dsa_tree_teardown_master\n   -> dsa_master_teardown\n      -> unsets master->dsa_ptr, making no further packets match the\n         ETH_P_XDSA packet type handler\n-> dsa_tree_teardown_ports\n   -> dsa_port_teardown\n      -> dsa_slave_destroy\n         -> unregisters DSA net devices, there is even a synchronize_net()\n            in unregister_netdevice_many()\n-> dsa_tree_teardown_switches\n   -> dsa_switch_teardown\n      -> dsa_switch_teardown_tag_protocol\n         -> finally frees the tagger-owned storage","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":[],"references":["https://git.kernel.org/stable/c/4e0c19fcb8b5323716140fa82b79aa9f60e60407","https://git.kernel.org/stable/c/5809fb03942dbac25144db5bebea84fa003ecaca"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:01:22.920403922+00:00"},"epss":{"cve":"CVE-2022-49808","score":0.0017,"percentile":0.06381,"date":"2026-11-01"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}