From c95af0fcd391f5120490d44e36ca5033a7a521a7 Mon Sep 17 00:00:00 2001 From: markj Date: Mon, 25 Apr 2016 18:40:57 +0000 Subject: [PATCH] Allow DOF sections with excessively long probe function components. Without this change, DTrace will refuse to load a DOF section if the function component of any of its probes exceeds DTRACE_FUNCNAMELEN (128). Probes in C++ programs can have very long function components. Rather than rejecting all probes if a single probe exceeds the limit, simply skip the invalid probe and emit a warning. This ensures that valid probes are instantiated. PR: 207735 MFC after: 2 weeks --- .../contrib/opensolaris/uts/common/dtrace/dtrace.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/sys/cddl/contrib/opensolaris/uts/common/dtrace/dtrace.c b/sys/cddl/contrib/opensolaris/uts/common/dtrace/dtrace.c index 00129751769e..086d7786b93c 100644 --- a/sys/cddl/contrib/opensolaris/uts/common/dtrace/dtrace.c +++ b/sys/cddl/contrib/opensolaris/uts/common/dtrace/dtrace.c @@ -9355,6 +9355,10 @@ dtrace_helper_provide_one(dof_helper_t *dhp, dof_sec_t *sec, pid_t pid) probe = (dof_probe_t *)(uintptr_t)(daddr + prb_sec->dofs_offset + i * prb_sec->dofs_entsize); + /* See the check in dtrace_helper_provider_validate(). */ + if (strlen(strtab + probe->dofpr_func) >= DTRACE_FUNCNAMELEN) + continue; + dhpb.dthpb_mod = dhp->dofhp_mod; dhpb.dthpb_func = strtab + probe->dofpr_func; dhpb.dthpb_name = strtab + probe->dofpr_name; @@ -16042,7 +16046,13 @@ dtrace_helper_provider_validate(dof_hdr_t *dof, dof_sec_t *sec) if (strlen(strtab + probe->dofpr_func) >= DTRACE_FUNCNAMELEN) { dtrace_dof_error(dof, "function name too long"); - return (-1); + /* + * Keep going if the function name is too long. + * Unlike provider and probe names, we cannot reasonably + * impose restrictions on function names, since they're + * a property of the code being instrumented. We will + * skip this probe in dtrace_helper_provide_one(). + */ } if (probe->dofpr_name >= str_sec->dofs_size ||