In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
bpf: Disallow interpreter fallback for BPF_ADDR_PERCPU insn<\/p>\n
The BPF_MOV64_PERCPU_REG insn requires JIT to emit native code to for
\n‘dst_reg = src_reg + ‘.<\/p>\n
However, the interpreter ignores the ‘off’ at its ALU64_MOV_X label.
\nThe ‘off’ indicates the insn is BPF_MOV64_PERCPU_REG insn. Then, when
\nthe interpreter loads memory from the register, it will hit a page
\nfault.<\/p>\n
[ 2.545572] BUG: unable to handle page fault for address: ffffffffacaaf034
\n[ 2.546485] #PF: supervisor read access in kernel mode
\n[ 2.547167] #PF: error_code(0x0000) – not-present page
\n[ 2.547850] PGD 134e63067 P4D 134e63067 PUD 134e64063 PMD 10021c063 PTE 800ffffeca550062
\n[ 2.548912] Oops: Oops: 0000 [#1] SMP PTI<\/p>\n
Set jit_required as true in order to disallow interpreter fallback in
\ncore.c::__bpf_prog_select_runtime(), if any BPF_ADDR_PERCPU insn is
\npatched to the prog.<\/p>\n
BTW, rename the helper bpf_map_supports_cpu_flags() to
\nbpf_map_is_percpu_map().<\/p>\n","protected":false},"excerpt":{"rendered":"
In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
bpf: Disallow interpreter fallback for BPF_ADDR_PERCPU insn<\/p>\n
The BPF_MOV64_PERCPU_REG insn requires JIT to emit native code to for<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-28534","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/28534","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln"}],"about":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/types\/vuln"}],"wp:attachment":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=28534"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=28534"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=28534"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}