Описание
In the Linux kernel, the following vulnerability has been resolved:
bpf: copy_verifier_state() should copy 'loop_entry' field
The bpf_verifier_state.loop_entry state should be copied by copy_verifier_state(). Otherwise, .loop_entry values from unrelated states would poison env->cur_state.
Additionally, env->stack should not contain any states with .loop_entry != NULL. The states in env->stack are yet to be verified, while .loop_entry is set for states that reached an equivalent state. This means that env->cur_state->loop_entry should always be NULL after pop_stack().
See the selftest in the next commit for an example of the program that is not safe yet is accepted by verifier w/o this fix.
This change has some verification performance impact for selftests:
File Program Insns (A) Insns (B) Insns (DIFF) States (A) States (B) States (DIFF)
EPSS
Дефекты
Связанные уязвимости
In the Linux kernel, the following vulnerability has been resolved: bpf: copy_verifier_state() should copy 'loop_entry' field The bpf_verifier_state.loop_entry state should be copied by copy_verifier_state(). Otherwise, .loop_entry values from unrelated states would poison env->cur_state. Additionally, env->stack should not contain any states with .loop_entry != NULL. The states in env->stack are yet to be verified, while .loop_entry is set for states that reached an equivalent state. This means that env->cur_state->loop_entry should always be NULL after pop_stack(). See the selftest in the next commit for an example of the program that is not safe yet is accepted by verifier w/o this fix. This change has some verification performance impact for selftests: File Program Insns (A) Insns (B) Insns (DIFF) States (A) States (B) States (DIFF) ---------------------------------- ---------------------------- --------- -------...
In the Linux kernel, the following vulnerability has been resolved: b ...
In the Linux kernel, the following vulnerability has been resolved: bpf: copy_verifier_state() should copy 'loop_entry' field The bpf_verifier_state.loop_entry state should be copied by copy_verifier_state(). Otherwise, .loop_entry values from unrelated states would poison env->cur_state. Additionally, env->stack should not contain any states with .loop_entry != NULL. The states in env->stack are yet to be verified, while .loop_entry is set for states that reached an equivalent state. This means that env->cur_state->loop_entry should always be NULL after pop_stack(). See the selftest in the next commit for an example of the program that is not safe yet is accepted by verifier w/o this fix. This change has some verification performance impact for selftests: File Program Insns (A) Insns (B) Insns (DIFF) States (A) States (B) States (DIFF) ---------------------------------- ---------------------------- --------- -----...
EPSS