platform/x86/amd/pmc: Fix LPS0 and debugfs leaks when STB init fails
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 6.18.50, 7.2.4
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
In the Linux kernel, the following vulnerability has been resolved: platform/x86/amd/pmc: Fix LPS0 and debugfs leaks when STB init fails amd_pmc_probe() registers the LPS0 s2idle handler with acpi_register_lps0_dev() and creates the driver's debugfs directory before calling amd_stb_s2d_init(), which is the last step in probe that can fail. When amd_stb_s2d_init() fails (for example the S2D telemetry region cannot be ioremapped on a long-running system, or the SMU rejects the S2D setup) the error path only calls pci_dev_put() and returns. This leaves amd_pmc_s2idle_dev_ops on the global lps0_s2idle_devops_head list and leaks the debugfs directory, while the devm-managed resources backing the handler are torn down. Reloading the module then walks the corrupted list in acpi_register_lps0_dev() and hits: list_add corruption. next->prev should be prev, but was NULL. kernel BUG at lib/list_debug.c:29! acpi_register_lps0_dev+0x44/0x80 amd_pmc_probe+0x224/0x380 [amd_pmc] platform_probe+0x67/0x90 Even without a reload, the stale registration means the next s2idle transition calls into torn-down driver state. Unwind the debugfs directory and the LPS0 registration on the amd_stb_s2d_init() error path. acpi_unregister_lps0_dev() is safe to call unconditionally here: it is guarded on the same conditions as acpi_register_lps0_dev(), which is exactly what amd_pmc_remove() already relies on.
Timeline
- CVE published
- Record last updated
Affected versions
- Linux Linux
From 49de59f69a76f538bfa5d0638a8c98d052546567 · fixed in d201c09c2428a4a8fd3bdcb032ae99f1e016458c; From 83ad6974dd3bf34c080b3c08d36d02ebc3bd6da8 · fixed in bc9aa5fe21c3966c80647ed6574b94b863f23c62; From 83ad6974dd3bf34c080b3c08d36d02ebc3bd6da8 · fixed in 30e5f4d0cd0be655c800f10ae3e530391aa6c1b5; From 83ad6974dd3bf34c080b3c08d36d02ebc3bd6da8 · fixed in 76f650a76d6a36a4bee79d94db90a0e935a95477
- Linux Linux
6.14
- KernelLinux
From 6.14.0 · fixed in 6.18.50; From 6.19.0 · fixed in 7.2.4