[SRU][Q/N:linux-azure][PATCH v2 0/1] azure: backport "net: hv_netvsc: reject RSS hash key programming without RX indirection table"

[Vinicius Peixoto]

BugLink: https://bugs.launchpad.net/bugs/2142703

[Impact]

RSS configuration requires a valid RX indirection table. However, if the
network device reports only a single RX queue, an indirection table will
not be allocated. hv_netvsc currently does not check for this and
attempting to set the RSS hash key will hang VMs on Azure.

[Fix]

Backport the following fix:

d23564955811 ("net: hv_netvsc: reject RSS hash key programming without RX indirection table")

[Test plan]

Build tested only; Azure will run reproducers on their side to validate the fix.

[Where problems could occur]

This is small, self-contained and has no side effects, but will change
the behavior of the hv_netvsc module upon an invalid RSS hash key update
operation, which could cause issues related to network packet reception
for machines with multiple receive queues on Azure.

[Other info]
SF #00427202

[Changelog]
v1 -> v2: remove Jammy from the patchset since in that kernel the
rx_table within struct net_device_context is statically allocated and
accessing it inside netvsc_set_rxfh() will not cause a null pointer
dereference.

Aditya Garg (1):
  net: hv_netvsc: reject RSS hash key programming without RX indirection
    table

 drivers/net/hyperv/netvsc_drv.c | 3 +++
 1 file changed, 3 insertions(+)

-- 
2.51.0