Description
In the Linux kernel, the following vulnerability has been resolved: tracepoint: balance regfunc() on func_add() failure in tracepoint_add_func() When a tracepoint goes through the 0 -> 1 transition, tracepoint_add_func() invokes the subsystem's ext->regfunc() before attempting to install the new probe via func_add(). If func_add() then fails (for example, when allocate_probes() cannot allocate a new probe array under memory pressure and returns -ENOMEM), the function returns the error without calling the matching ext->unregfunc(), leaving the side effects of regfunc() behind with no installed probe to justify them. For syscall tracepoints this is particularly unpleasant: syscall_regfunc() bumps sys_tracepoint_refcount and sets SYSCALL_TRACEPOINT on every task. After a leaked failure, the refcount is stuck at a non-zero value with no consumer, and every task continues paying the syscall trace entry/exit overhead until reboot. Other subsystems providing regfunc()/unregfunc() pairs exhibit similarly scoped persistent state. Mirror the existing 1 -> 0 cleanup and call ext->unregfunc() in the func_add() error path, gated on the same condition used there so the unwind is symmetric with the registration.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
8cf868affdc459beee1a941df0cfaba1673740e3 to < 5787052e5f69beb649f3d6a80a8aa37d9e683e4eaffected8cf868affdc459beee1a941df0cfaba1673740e3 to < 4f1756d043e56ea2e9a6c858fb290a0cf6fc2251affected8cf868affdc459beee1a941df0cfaba1673740e3 to < 36ff362235307af95152d510b53c2d9b8773a342affected8cf868affdc459beee1a941df0cfaba1673740e3 to < 247ed8a969f981bfba3112fd4bb441eaa6cef59caffected8cf868affdc459beee1a941df0cfaba1673740e3 to < 7bcadb3c2bc1cf60690e931aadd35fb7bd646a49affected8cf868affdc459beee1a941df0cfaba1673740e3 to < 2c5b8eeea006eb694c81631cd5713d494b80be90affected8cf868affdc459beee1a941df0cfaba1673740e3 to < 342829e042ac00f3d68d442ea92873fb6683f494affected8cf868affdc459beee1a941df0cfaba1673740e3 to < fad217e16fded7f3c09f8637b0f6a224d58b5f2eaffected
Linux Linux
Default version status: affected
4.10affected0 to < 4.10unaffected5.10.259 to ≤ 5.10.*unaffected5.15.210 to ≤ 5.15.*unaffected6.1.176 to ≤ 6.1.*unaffected6.6.140 to ≤ 6.6.*unaffected6.12.88 to ≤ 6.12.*unaffected6.18.30 to ≤ 6.18.*unaffected7.0.7 to ≤ 7.0.*unaffected7.1 to ≤ *unaffected
References
- https://git.kernel.org/stable/c/5787052e5f69beb649f3d6a80a8aa37d9e683e4e ↗
- https://git.kernel.org/stable/c/4f1756d043e56ea2e9a6c858fb290a0cf6fc2251 ↗
- https://git.kernel.org/stable/c/36ff362235307af95152d510b53c2d9b8773a342 ↗
- https://git.kernel.org/stable/c/247ed8a969f981bfba3112fd4bb441eaa6cef59c ↗
- https://git.kernel.org/stable/c/7bcadb3c2bc1cf60690e931aadd35fb7bd646a49 ↗
- https://git.kernel.org/stable/c/2c5b8eeea006eb694c81631cd5713d494b80be90 ↗
- https://git.kernel.org/stable/c/342829e042ac00f3d68d442ea92873fb6683f494 ↗
- https://git.kernel.org/stable/c/fad217e16fded7f3c09f8637b0f6a224d58b5f2e ↗
- https://cert-portal.siemens.com/productcert/html/ssa-784472.html ↗