CVE-2022-50883

In the Linux kernel, the following vulnerability has been resolved:

bpf: Prevent decltag from being referenced in funcproto arg

Syzkaller managed to hit another decl_tag issue:

btffuncprotocheck kernel/bpf/btf.c:4506 [inline] btfcheckalltypes kernel/bpf/btf.c:4734 [inline] btfparsetypesec+0x1175/0x1980 kernel/bpf/btf.c:4763 btfparse kernel/bpf/btf.c:5042 [inline] btfnewfd+0x65a/0xb00 kernel/bpf/btf.c:6709 bpfbtfload+0x6f/0x90 kernel/bpf/syscall.c:4342 __sys_bpf+0x50a/0x6c0 kernel/bpf/syscall.c:5034 __dosysbpf kernel/bpf/syscall.c:5093 [inline] __sesysbpf kernel/bpf/syscall.c:5091 [inline] __x64sysbpf+0x7c/0x90 kernel/bpf/syscall.c:5091 dosyscall64+0x54/0x70 arch/x86/entry/common.c:48

This seems similar to commit ea68376c8bed ("bpf: prevent decltag from being referenced in funcproto") but for the argument.