In the Linux kernel, the following vulnerability has been resolved:
fou: remove warn in gue_gro_receive on unsupported protocol
Drop the WARN_ON_ONCE inn gue_gro_receive if the encapsulated type is not known or does not have a GRO handler.
Such a packet is easily constructed. Syzbot generates them and sets off this warning.
Remove the warning as it is expected and not actionable.
The warning was previously reduced from WARN_ON to WARN_ON_ONCE in commit 270136613bf7 ("fou: Do WARN_ON_ONCE in gue_gro_receive for bad proto callbacks").
Exploitability
AV:NAC:LPR:NUI:NScope
S:UImpact
C:NI:NA:H7.5/CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H