reference count leaks which are caused by:
- VMA splits, which change the offset or size of a mapping, which causes
perf_mmap_close() to ignore the unmap or unmap the wrong buffer.
- Several internal issues of perf_mmap(), which can cause reference count
leaks in the perf mmap, corrupt accounting or cause leaks in perf
drivers.
The main fix is to prevent VMA splits by implementing the [may_]split()
callback for vm operations. The other issues are addressed by rearranging
code, early returns on failure and invocation of cleanups.
Also provide a selftest to validate the fixes.
The reference counting should be converted to refcount_t, but that requires
larger refactoring of the code and will be done once these fixes are
upstream.
-----BEGIN PGP SIGNATURE-----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=B9L/
-----END PGP SIGNATURE-----
Merge tag 'perf-fixes-27504' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git
Pull perf fixes from Thomas Gleixner:
"Perf fixes for perf_mmap() reference counting to prevent potential
reference count leaks which are caused by:
- VMA splits, which change the offset or size of a mapping, which
causes perf_mmap_close() to ignore the unmap or unmap the wrong
buffer.
- Several internal issues of perf_mmap(), which can cause reference
count leaks in the perf mmap, corrupt accounting or cause leaks in
perf drivers.
The main fix is to prevent VMA splits by implementing the
[may_]split() callback for vm operations.
The other issues are addressed by rearranging code, early returns on
failure and invocation of cleanups.
Also provide a selftest to validate the fixes.
The reference counting should be converted to refcount_t, but that
requires larger refactoring of the code and will be done once these
fixes are upstream"
* tag 'perf-fixes-27504' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git:
selftests/perf_events: Add a mmap() correctness test
perf/core: Prevent VMA split of buffer mappings
perf/core: Handle buffer mapping fail correctly in perf_mmap()
perf/core: Exit early on perf_mmap() fail
perf/core: Don't leak AUX buffer refcount on allocation failure
perf/core: Preserve AUX buffer allocation failure result
|
||
|---|---|---|
| .. | ||
| accounting | ||
| arch | ||
| bootconfig | ||
| bpf | ||
| build | ||
| certs | ||
| cgroup | ||
| counter | ||
| crypto | ||
| debugging | ||
| firewire | ||
| firmware | ||
| gpio | ||
| hv | ||
| iio | ||
| include | ||
| kvm/kvm_stat | ||
| laptop | ||
| leds | ||
| lib | ||
| memory-model | ||
| mm | ||
| net | ||
| objtool | ||
| pcmcia | ||
| perf | ||
| power | ||
| rcu | ||
| sched | ||
| sched_ext | ||
| scripts | ||
| sound | ||
| spi | ||
| testing | ||
| thermal | ||
| time | ||
| tracing | ||
| usb | ||
| verification | ||
| virtio | ||
| wmi | ||
| workqueue | ||
| writeback | ||
| Makefile | ||