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| author | Ben Hutchings <ben@decadent.org.uk> | 2017-12-23 02:26:17 +0000 |
|---|---|---|
| committer | Michael Bestas <mkbestas@lineageos.org> | 2022-04-19 00:51:18 +0300 |
| commit | 9dec46f1b30e36464ab860b0e00f3694304a45d2 (patch) | |
| tree | db34e3ec827f81ca604a639b8e6a5e2e0a31f144 /kernel/bpf/syscall.c | |
| parent | 331501cd097baa6360a3cfd2f9d4a1122195ac39 (diff) | |
bpf/verifier: Fix states_equal() comparison of pointer and UNKNOWN
An UNKNOWN_VALUE is not supposed to be derived from a pointer, unless
pointer leaks are allowed. Therefore, states_equal() must not treat
a state with a pointer in a register as "equal" to a state with an
UNKNOWN_VALUE in that register.
This was fixed differently upstream, but the code around here was
largely rewritten in 4.14 by commit f1174f77b50c "bpf/verifier: rework
value tracking". The bug can be detected by the bpf/verifier sub-test
"pointer/scalar confusion in state equality check (way 1)".
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Edward Cree <ecree@solarflare.com>
Cc: Jann Horn <jannh@google.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
Diffstat (limited to 'kernel/bpf/syscall.c')
0 files changed, 0 insertions, 0 deletions