There are two issues with the way psp_dev is used in nsim_do_psp():
1. There is no check for IS_ERR() on the peers psp_dev, before
dereferencing.
2. The refcount on this psp_dev can be dropped by
nsim_psp_rereg_write()
To fix this, we can make netdevsim's reference to its psp_dev an rcu
reference, and then nsim_do_psp() can read the fields it needs from an
rcu critical section.
Fixes: f857478d62 ("netdevsim: a basic test PSP implementation")
Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260505-psd-rcu-v1-3-a8f69ec1ab96@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The debugfs write handler, nsim_psp_rereg_write(), can race against
nsim_destroy() and against itself, causing nsim_psp_uninit() to run
more than once concurrently. Two complementary changes serialize all
callers:
1. Delete the psp_rereg debugfs file from nsim_psp_uninit() before
doing the actual teardown. debugfs_remove() drains any in-flight
writers and prevents new ones from starting.
2. Add a mutex around the body of nsim_psp_rereg_write() so that two
concurrent userspace writers cannot both enter the teardown path
at once.
The teardown work itself is moved into a new __nsim_psp_uninit() that
the rereg handler calls under the mutex, while the public
nsim_psp_uninit() wraps it with the debugfs_remove()/mutex_destroy()
pair so nsim_destroy() doesn't have to know about the psp internals.
Fixes: f857478d62 ("netdevsim: a basic test PSP implementation")
Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260505-psd-rcu-v1-2-a8f69ec1ab96@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
On 64bit arches, struct u64_stats_sync is empty and provides no help
against load/store tearing. Convert to u64_stats_t to ensure atomic
operations.
Signed-off-by: David Yang <mmyangfl@gmail.com>
Link: https://patch.msgid.link/20260123211101.2929547-1-mmyangfl@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
For now only tx/rx packets/bytes are reported. This is not compliant
with the PSP Architecture Specification.
Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com>
Link: https://patch.msgid.link/20251106002608.1578518-6-daniel.zahka@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Provide a PSP implementation for netdevsim.
Use psp_dev_encapsulate() and psp_dev_rcv() to do actual encapsulation
and decapsulation on skbs, but perform no encryption or decryption. In
order to make encryption with a bad key result in a drop on the peer's
rx side, we stash our psd's generation number in the first byte of each
key before handing to the peer.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Co-developed-by: Daniel Zahka <daniel.zahka@gmail.com>
Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com>
Link: https://patch.msgid.link/20250927225420.1443468-2-kuba@kernel.org
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
