Age | Commit message (Collapse) | Author | |
---|---|---|---|
2017-08-08 | bpf/verifier: track signed and unsigned min/max values | Edward Cree | |
Allows us to, sometimes, combine information from a signed check of one bound and an unsigned check of the other. We now track the full range of possible values, rather than restricting ourselves to [0, 1<<30) and considering anything beyond that as unknown. While this is probably not necessary, it makes the code more straightforward and symmetrical between signed and unsigned bounds. Signed-off-by: Edward Cree <ecree@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net> | |||
2017-08-08 | bpf/verifier: rework value tracking | Edward Cree | |
Unifies adjusted and unadjusted register value types (e.g. FRAME_POINTER is now just a PTR_TO_STACK with zero offset). Tracks value alignment by means of tracking known & unknown bits. This also replaces the 'reg->imm' (leading zero bits) calculations for (what were) UNKNOWN_VALUEs. If pointer leaks are allowed, and adjust_ptr_min_max_vals returns -EACCES, treat the pointer as an unknown scalar and try again, because we might be able to conclude something about the result (e.g. pointer & 0x40 is either 0 or 0x40). Verifier hooks in the netronome/nfp driver were changed to match the new data structures. Signed-off-by: Edward Cree <ecree@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net> |