Alex Gartrell 24b4d2abd0 ebpf: Allow dereferences of PTR_TO_STACK registers ... mov %rsp, %r1 ; r1 = rsp add $-8, %r1 ; r1 = rsp - 8 store_q $123, -8(%rsp) ; *(u64*)r1 = 123 <- valid store_q $123, (%r1) ; *(u64*)r1 = 123 <- previously invalid mov $0, %r0 exit ; Always need to exit And we'd get the following error: 0: (bf) r1 = r10 1: (07) r1 += -8 2: (7a) *(u64 *)(r10 -8) = 999 3: (7a) *(u64 *)(r1 +0) = 999 R1 invalid mem access 'fp' Unable to load program We already know that a register is a stack address and the appropriate offset, so we should be able to validate those references as well. Signed-off-by: Alex Gartrell <agartrell@fb.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>		2015-07-27 00:54:10 -07:00
..
arraymap.c	bpf: add missing rcu protection when releasing programs from prog_array	2015-05-31 00:27:51 -07:00
core.c	test_bpf: add bpf_skb_vlan_push/pop() tests	2015-07-20 20:52:32 -07:00
hashtab.c	ebpf: constify various function pointer structs	2015-03-01 14:05:18 -05:00
helpers.c	bpf: introduce current->pid, tgid, uid, gid, comm accessors	2015-06-15 15:53:50 -07:00
Makefile	ebpf: remove kernel test stubs	2015-03-01 14:05:18 -05:00
syscall.c	bpf: add missing rcu protection when releasing programs from prog_array	2015-05-31 00:27:51 -07:00
verifier.c	ebpf: Allow dereferences of PTR_TO_STACK registers	2015-07-27 00:54:10 -07:00