Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix overflow of jump offset in constant blinding bpf_jit_blind_insn() rewrites 'if rX op imm goto off' into: AX = imm ^ rnd AX ^= rnd if rX op AX goto off and subtracts 2 from off when the jump is backward. off is s16, so -32767 and -32768 wrap and the jump goes 32767 insns forward, past the end of the prog. The jump is inside the patch, hence bpf_adj_branches() doesn't check it. The kernel crashes when such prog runs with bpf_jit_harden=2. Return -ERANGE in such case. bpf_jit_blind_constants() fails the same way when blinding of other insns moves a jump out of range.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected 4f3446bb809f20ad56cadf712e6006815ae7a8f9 before 443328237113ee0ea515e506497334d871dbc2aa; affected 4f3446bb809f20ad56cadf712e6006815ae7a8f9 before ad139384ecddb6f3e7e3c3c12765aafae0e39670 |
| Linux / Linux | affected 4.7; unaffected 0 before 4.7; unaffected 7.2.10 through 7.2.*; unaffected 7.3 through * |
CWE
No CWE identifiers supplied.