CVE-2023-54259
Description
In the Linux kernel, the following vulnerability has been resolved:
soundwire: bus: Fix unbalanced pm_runtime_put() causing usage count underflow
This reverts commit
443a98e649b4 ('soundwire: bus: use pm_runtime_resume_and_get()')
Change calls to pm_runtime_resume_and_get() back to pm_runtime_get_sync().
This fixes a usage count underrun caused by doing a pm_runtime_put() even
though pm_runtime_resume_and_get() returned an error.
The three affected functions ignore -EACCES error from trying to get
pm_runtime, and carry on, including a put at the end of the function.
But pm_runtime_resume_and_get() does not increment the usage count if it
returns an error. So in the -EACCES case you must not call
pm_runtime_put().
The documentation for pm_runtime_get_sync() says:
'Consider using pm_runtime_resume_and_get() ... as this is likely to
result in cleaner code.'
In this case I don't think it results in cleaner code because the
pm_runtime_put() at the end of the function would have to be conditional on
the return value from pm_runtime_resume_and_get() at the top of the
function.
pm_runtime_get_sync() doesn't have this problem because it always
increments the count, so always needs a put. The code can just flow through
and do the pm_runtime_put() unconditionally.
EPSS (Exploit Prediction Scoring System)
EPSS (Exploit Prediction Scoring System)
Prevede la probabilità di sfruttamento basata su intelligence sulle minacce e sulle caratteristiche della vulnerabilità.