In the Linux kernel, the following vulnerability has been resolved:
liquidio: Adjust a NULL pointer handling path in liovfrepcopypacket
In liovfrepcopypacket() pginfo->page is compared to a NULL value, but then it is unconditionally passed to skbaddrxfrag() which looks strange and could lead to null pointer dereference.
liovfrepcopypacket() call trace looks like: octeondroqprocesspackets octeondroqfastprocesspackets octeondroqdispatchpkt octeoncreaterecvinfo ...search in the dispatchlist... ->dispfn(rdisp->rinfo, ...) liovfreppktrecv(struct octeonrecvinfo *recvinfo, ...) In this path there is no code which sets pginfo->page to NULL. So this check looks unneeded and doesn't solve potential problem. But I guess the author had reason to add a check and I have no such card and can't do real test. In addition, the code in the function liquidiopushpacket() in liquidio/liocore.c does exactly the same.
Based on this, I consider the most acceptable compromise solution to adjust this issue by moving skbaddrx_frag() into conditional scope.
Found by Linux Verification Center (linuxtesting.org) with SVACE.