Affected: Linux

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

tracing/osnoise: Fix resetting of tracepoints

If a timerlat tracer is started with the osnoise option OSNOISE_WORKLOAD disabled, but then that option is enabled and timerlat is removed, the tracepoints that were enabled on timerlat registration do not get disabled. If the option is disabled again and timelat is started, then it triggers a warning in the tracepoint code due to registering the tracepoint again without ever disabling it.

Do not use the same user space defined options to know to disable the tracepoints when timerlat is removed. Instead, set a global flag when it is enabled and use that flag to know to disable the events.

~# echo NO_OSNOISE_WORKLOAD > /sys/kernel/tracing/osnoise/options ~# echo timerlat > /sys/kernel/tracing/current_tracer ~# echo OSNOISE_WORKLOAD > /sys/kernel/tracing/osnoise/options ~# echo nop > /sys/kernel/tracing/current_tracer ~# echo NO_OSNOISE_WORKLOAD > /sys/kernel/tracing/osnoise/options ~# echo timerlat > /sys/kernel/tracing/current_tracer

Triggers:

------------[ cut here ]------------ WARNING: CPU: 6 PID: 1337 at kernel/tracepoint.c:294 tracepoint_add_func+0x3b6/0x3f0 Modules linked in: CPU: 6 UID: 0 PID: 1337 Comm: rtla Not tainted 6.13.0-rc4-test-00018-ga867c441128e-dirty #73 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 RIP: 0010:tracepoint_add_func+0x3b6/0x3f0 Code: 48 8b 53 28 48 8b 73 20 4c 89 04 24…