On Mon, Mar 19, 2018 at 3:43 PM, Matt Joras <mjo...@freebsd.org> wrote: > Author: mjoras > Date: Mon Mar 19 22:43:27 2018 > New Revision: 331227 > URL: https://svnweb.freebsd.org/changeset/base/331227 > > Log: > Fix initialization of eventhandler mutex. > > mtx_init does not do a copy of the name string it is passed. The > eventhandler code incorrectly passed the parameter string directly to > mtx_init instead of using the copy it makes. This was an existing > problem with the code that I dutifully copied over in my changes in r325621.
For those without context: The problem here is that the name string comes from rodata of whatever module *registers* an eventhandler listener, but isn't tied to the lifetime of that module. So for example, filemon.ko or hwpmc.ko. If those modules are subsequently unloaded, the kernel eventhandler lock lo_names continue to point to the (now stale) module memory, resulting in kernel page fault crashes if/when those names are eventually dereferenced (we hit it with "sysctl kern.proc.all" after one of those modules was unloaded). Best, Conrad _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
