void emit_global_init (vardecl* v);
void emit_global_param (vardecl* v);
void emit_functionsig (functiondecl* v);
+ void emit_unprivileged_user_check ();
void emit_module_init ();
void emit_module_exit ();
void emit_function (functiondecl* v);
o->newline() << "static atomic_t session_state = ATOMIC_INIT (STAP_SESSION_STARTING);";
o->newline() << "static atomic_t error_count = ATOMIC_INIT (0);";
o->newline() << "static atomic_t skipped_count = ATOMIC_INIT (0);";
- o->newline() << "#ifdef STP_TIMING";
o->newline() << "static atomic_t skipped_count_lowstack = ATOMIC_INIT (0);";
o->newline() << "static atomic_t skipped_count_reentrant = ATOMIC_INIT (0);";
o->newline() << "static atomic_t skipped_count_uprobe_reg = ATOMIC_INIT (0);";
o->newline() << "static atomic_t skipped_count_uprobe_unreg = ATOMIC_INIT (0);";
- o->newline() << "#endif";
o->newline();
o->newline() << "struct context {";
o->newline(1) << "atomic_t busy;";
ostringstream oss;
oss << "c->statp = & time_" << dp->basest()->name << ";" << endl; // -t anti-dupe
oss << "# needs_global_locks: " << dp->needs_global_locks () << endl;
+ dp->print_dupe_stamp (oss);
dp->body->print(oss);
// NB: dependent probe conditions *could* be listed here, but don't need to be.
// That's because they're only dependent on the probe body, which is already
}
+void
+c_unparser::emit_unprivileged_user_check ()
+{
+ // If the --unprivileged option was specified then the module
+ // will be safe for unprivileged users, if it is successfully generated,
+ // so no check need be emitted.
+ if (session->unprivileged)
+ return;
+
+ // Otherwise, generate code to check whether the user is unprivileged.
+ // If so, then generate an error and indicate that the check has failed.
+ o->newline();
+ o->newline() << "static int systemtap_unprivileged_user_check (void) {";
+ o->newline(1) << "if (! _stp_unprivileged_user)";
+ o->newline(1) << "return 0;";
+
+ o->newline(-1) << "_stp_error (\"You are attempting to run stap as an ordinary user.\");";
+ o->newline() << "_stp_error (\"Your module must be compiled using the --unprivileged option.\");";
+ o->newline() << "return 1;";
+
+ o->newline(-1) << "}\n";
+}
+
void
c_unparser::emit_module_init ()
o->newline() << "if (_stp_module_check()) rc = -EINVAL;";
o->newline(-1) << "}";
+
+ if (! session->unprivileged) {
+ // Check whether the user is unprivileged.
+ o->newline() << "if (systemtap_unprivileged_user_check ()) rc = -EINVAL;";
+ }
+
o->newline() << "if (rc) goto out;";
o->newline() << "(void) probe_point;";
o->newline() << getvar (v).fini();
}
+ // For any partially registered/unregistered kernel facilities.
+ o->newline() << "#ifdef STAPCONF_SYNCHRONIZE_SCHED";
+ o->newline() << "synchronize_sched();";
+ o->newline() << "#endif";
+
o->newline() << "return rc;";
o->newline(-1) << "}\n";
}
o->newline() << "#endif";
}
- // print final error/reentrancy counts if non-zero
+ // print final error/skipped counts if non-zero
o->newline() << "if (atomic_read (& skipped_count) || "
- << "atomic_read (& error_count)) {";
+ << "atomic_read (& error_count) || "
+ << "atomic_read (& skipped_count_reentrant)) {"; // PR9967
o->newline(1) << "_stp_warn (\"Number of errors: %d, "
<< "skipped probes: %d\\n\", "
<< "(int) atomic_read (& error_count), "
// be very different with or without -t.
oss << "c->statp = & time_" << v->basest()->name << ";" << endl;
+ v->print_dupe_stamp (oss);
v->body->print(oss);
// Since the generated C changes based on whether or not the probe
void
c_unparser::visit_target_symbol (target_symbol* e)
{
- throw semantic_error("cannot translate general target-symbol expression", e->tok);
+ if (!e->probe_context_var.empty())
+ o->line() << "l->" << e->probe_context_var;
+ else
+ throw semantic_error("cannot translate general cast expression", e->tok);
}
assert (rvalue->type == pe_long);
mapvar mvar = parent->getmap (array->referent, e->tok);
- // o->newline() << "c->last_stmt = " << lex_cast_qstring(*e->tok) << ";";
+ o->newline() << "c->last_stmt = " << lex_cast_qstring(*e->tok) << ";";
o->newline() << mvar.add (idx, rvar) << ";";
res = rvar;
// no need for these dummy assignments
else
{
mapvar mvar = parent->getmap (array->referent, e->tok);
- // o->newline() << "c->last_stmt = " << lex_cast_qstring(*e->tok) << ";";
+ o->newline() << "c->last_stmt = " << lex_cast_qstring(*e->tok) << ";";
if (op != "=") // don't bother fetch slot if we will just overwrite it
parent->c_assign (lvar, mvar.get(idx), e->tok);
c_assignop (res, lvar, rvar, e->tok);
int use_print = 0;
string format_string = print_format::components_to_string(components);
- if (tmp.size() == 0 || (tmp.size() == 1 && format_string == "%s"))
+ if ((tmp.size() == 0 && format_string.find("%%") == std::string::npos)
+ || (tmp.size() == 1 && format_string == "%s"))
use_print = 1;
else if (tmp.size() == 1
&& e->args[0]->tok->type == tok_string
string modname = name;
+ if (pending_interrupts)
+ return DWARF_CB_ABORT;
+
// skip modules/files we're not actually interested in
if (c->session.unwindsym_modules.find(modname) == c->session.unwindsym_modules.end())
return DWARF_CB_OK;
// In the future, we'll also care about data symbols.
int syments = dwfl_module_getsymtab(m);
- assert(syments);
+ dwfl_assert ("Getting symbol table for " + modname, syments >= 0);
//extract build-id from debuginfo file
int build_id_len = 0;
// see https://bugzilla.redhat.com/show_bug.cgi?id=465872
// and http://sourceware.org/ml/systemtap/2008-q4/msg00579.html
#ifdef _ELFUTILS_PREREQ
-#if _ELFUTILS_PREREQ(0,138)
+ #if _ELFUTILS_PREREQ(0,138)
// Let's standardize to the buggy "end of build-id bits" behavior.
build_id_vaddr += build_id_len;
+ #endif
+ #if !_ELFUTILS_PREREQ(0,141)
+ #define NEED_ELFUTILS_BUILDID_WORKAROUND
+ #endif
+#else
+ #define NEED_ELFUTILS_BUILDID_WORKAROUND
#endif
+
+ // And check for another workaround needed.
+ // see https://bugzilla.redhat.com/show_bug.cgi?id=489439
+ // and http://sourceware.org/ml/systemtap/2009-q1/msg00513.html
+#ifdef NEED_ELFUTILS_BUILDID_WORKAROUND
+ if (build_id_vaddr < base && dwfl_module_relocations (m) == 1)
+ {
+ GElf_Addr main_bias;
+ dwfl_module_getelf (m, &main_bias);
+ build_id_vaddr += main_bias;
+ }
#endif
- if (c->session.verbose > 1) {
- clog << "Found build-id in " << name
- << ", length " << build_id_len;
- clog << ", end at 0x" << hex << build_id_vaddr
- << dec << endl;
- }
+ if (c->session.verbose > 1)
+ {
+ clog << "Found build-id in " << name
+ << ", length " << build_id_len;
+ clog << ", end at 0x" << hex << build_id_vaddr
+ << dec << endl;
+ }
}
+ // Get the canonical path of the main file for comparison at runtime.
+ // When given directly by the user through -d or in case of the kernel
+ // name and path might differ. path should be used for matching.
+ // Use end as sanity check when resolving symbol addresses and to
+ // calculate size for .dynamic and .absolute sections.
+ const char *mainfile;
+ Dwarf_Addr start, end;
+ dwfl_module_info (m, NULL, &start, &end, NULL, NULL, &mainfile, NULL);
+
// Look up the relocation basis for symbols
int n = dwfl_module_relocations (m);
// XXX: unfortunate duplication with tapsets.cxx:emit_address()
typedef map<Dwarf_Addr,const char*> addrmap_t; // NB: plain map, sorted by address
- vector<string> seclist; // encountered relocation bases (section names)
+ vector<pair<string,unsigned> > seclist; // encountered relocation bases
+ // (section names and sizes)
map<unsigned, addrmap_t> addrmap; // per-relocation-base sorted addrmap
Dwarf_Addr extra_offset = 0;
- for (int i = 1 /* XXX: why not 0? */ ; i < syments; ++i)
+ for (int i = 0; i < syments; ++i)
{
GElf_Sym sym;
- const char *name = dwfl_module_getsym(m, i, &sym, NULL);
+ GElf_Word shndxp;
+ const char *name = dwfl_module_getsym(m, i, &sym, &shndxp);
if (name)
{
// NB: Yey, we found the kernel's _stext value.
ki = dwfl_module_relocate_address (m, &extra_offset);
dwfl_assert ("dwfl_module_relocate_address extra_offset",
ki >= 0);
+ // Sadly dwfl_module_relocate_address is broken on
+ // elfutils < 0.138, so we need to adjust for the module
+ // base address outself. (see also below).
+ extra_offset = sym.st_value - base;
if (c->session.verbose > 2)
- clog << "Found kernel _stext 0x" << hex << extra_offset << dec << endl;
+ clog << "Found kernel _stext extra offset 0x" << hex << extra_offset << dec << endl;
}
- // We only need the function symbols to identify kernel-mode
- // PC's, so we omit undefined or "fake" absolute addresses.
- // These fake absolute addresses occur in some older i386
- // kernels to indicate they are vDSO symbols, not real
- // functions in the kernel.
- if (GELF_ST_TYPE (sym.st_info) == STT_FUNC &&
- ! (sym.st_shndx == SHN_UNDEF || sym.st_shndx == SHN_ABS))
+ // We are only interested in "real" symbols.
+ // We omit symbols that have suspicious addresses (before base,
+ // or after end).
+ if ((GELF_ST_TYPE (sym.st_info) == STT_FUNC ||
+ GELF_ST_TYPE (sym.st_info) == STT_OBJECT) // PR10000: also need .data
+ && !(sym.st_shndx == SHN_UNDEF // Value undefined,
+ || shndxp == (GElf_Word) -1 // in a non-allocated section,
+ || sym.st_value >= end // beyond current module,
+ || sym.st_value < base)) // before first section.
{
Dwarf_Addr sym_addr = sym.st_value;
+ Dwarf_Addr save_addr = sym_addr;
const char *secname = NULL;
if (n > 0) // only try to relocate if there exist relocation bases
{
- Dwarf_Addr save_addr = sym_addr;
int ki = dwfl_module_relocate_address (m, &sym_addr);
dwfl_assert ("dwfl_module_relocate_address", ki >= 0);
secname = dwfl_module_relocation_info (m, ki, NULL);
{
// This is a symbol within a (possibly relocatable)
// kernel image.
+
+ // We only need the function symbols to identify kernel-mode
+ // PC's, so we omit undefined or "fake" absolute addresses.
+ // These fake absolute addresses occur in some older i386
+ // kernels to indicate they are vDSO symbols, not real
+ // functions in the kernel. We also omit symbols that have
+ if (GELF_ST_TYPE (sym.st_info) == STT_FUNC
+ && sym.st_shndx == SHN_ABS)
+ continue;
+
secname = "_stext";
// NB: don't subtract session.sym_stext, which could be inconveniently NULL.
// Instead, sym_addr will get compensated later via extra_offset.
// Compute our section number
unsigned secidx;
for (secidx=0; secidx<seclist.size(); secidx++)
- if (seclist[secidx]==secname) break;
+ if (seclist[secidx].first==secname) break;
if (secidx == seclist.size()) // new section name
- seclist.push_back (secname);
+ {
+ // absolute, dynamic or kernel have just one relocation
+ // section, which covers the whole module address range.
+ unsigned size;
+ if (secidx == 0
+ && (n == 0
+ || (n == 1
+ && (strcmp(secname, ".dynamic") == 0
+ || strcmp(secname, "_stext") == 0))))
+ size = end - start;
+ else
+ {
+ Dwarf_Addr b;
+ Elf_Scn *scn;
+ GElf_Shdr *shdr, shdr_mem;
+ scn = dwfl_module_address_section (m, &save_addr, &b);
+ assert (scn != NULL);
+ shdr = gelf_getshdr(scn, &shdr_mem);
+ size = shdr->sh_size;
+ }
+ seclist.push_back (make_pair(secname,size));
+ }
(addrmap[secidx])[sym_addr] = name;
}
// There would be only a small benefit to warning. A user
// likely can't do anything about this; backtraces for the
// affected module would just get all icky heuristicy.
-#if 0
- c->session.print_warning ("No unwind data for " + modname
- + ", " + dwfl_errmsg (-1));
-#endif
+ // So only report in verbose mode.
+ if (c->session.verbose > 2)
+ c->session.print_warning ("No unwind data for " + modname
+ + ", " + dwfl_errmsg (-1));
}
for (unsigned secidx = 0; secidx < seclist.size(); secidx++)
}
c->output << "static struct _stp_section _stp_module_" << stpmod_idx<< "_sections[] = {\n";
+ // For the kernel, executables (ET_EXEC) or shared libraries (ET_DYN)
+ // there is just one section that covers the whole address space of
+ // the module. For kernel modules (ET_REL) there can be multiple
+ // sections that get relocated separately.
for (unsigned secidx = 0; secidx < seclist.size(); secidx++)
{
c->output << "{\n"
- << ".name = " << lex_cast_qstring(seclist[secidx]) << ",\n"
+ << ".name = " << lex_cast_qstring(seclist[secidx].first) << ",\n"
+ << ".size = 0x" << hex << seclist[secidx].second << dec << ",\n"
<< ".symbols = _stp_module_" << stpmod_idx << "_symbols_" << secidx << ",\n"
- << ".num_symbols = sizeof(_stp_module_" << stpmod_idx << "_symbols_" << secidx << ")/sizeof(struct _stp_symbol)\n"
+ << ".num_symbols = " << addrmap[secidx].size() << "\n"
<< "},\n";
}
c->output << "};\n";
c->output << "static struct _stp_module _stp_module_" << stpmod_idx << " = {\n";
c->output << ".name = " << lex_cast_qstring (modname) << ", \n";
+
+ mainfile = canonicalize_file_name(mainfile);
+ c->output << ".path = " << lex_cast_qstring (mainfile) << ",\n";
+
c->output << ".dwarf_module_base = 0x" << hex << base << dec << ", \n";
if (unwind != NULL)
// Emit symbol table & unwind data, plus any calls needed to register
// them with the runtime.
+void emit_symbol_data_done (unwindsym_dump_context*, systemtap_session&);
void
emit_symbol_data (systemtap_session& s)
unwindsym_dump_context ctx = { s, kallsyms_out, 0, s.unwindsym_modules };
+ // Micro optimization, mainly to speed up tiny regression tests
+ // using just begin probe.
+ if (s.unwindsym_modules.size () == 0)
+ {
+ emit_symbol_data_done(&ctx, s);
+ return;
+ }
+
// XXX: copied from tapsets.cxx dwflpp::, sadly
static const char *debuginfo_path_arr = "+:.debug:/usr/lib/debug:build";
static const char *debuginfo_env_arr = getenv("SYSTEMTAP_DEBUGINFO_PATH");
do
{
if (pending_interrupts) return;
+ if (ctx.undone_unwindsym_modules.empty()) break;
off = dwfl_getmodules (dwfl, &dump_unwindsyms, (void *) &ctx, 0);
}
while (off > 0);
{
NULL, /* dwfl_linux_kernel_find_elf, */
dwfl_standard_find_debuginfo,
- dwfl_offline_section_address,
+ NULL, /* ET_REL not supported for user space, only ET_EXEC and ET_DYN.
+ dwfl_offline_section_address, */
(char **) & debuginfo_path
};
do
{
if (pending_interrupts) return;
+ if (ctx.undone_unwindsym_modules.empty()) break;
off = dwfl_getmodules (dwfl, &dump_unwindsyms, (void *) &ctx, 0);
}
while (off > 0);
dwfl_end(dwfl);
}
+ emit_symbol_data_done (&ctx, s);
+}
+void
+emit_symbol_data_done (unwindsym_dump_context *ctx, systemtap_session& s)
+{
// Print out a definition of the runtime's _stp_modules[] globals.
- kallsyms_out << "\n";
- kallsyms_out << "static struct _stp_module *_stp_modules [] = {\n";
- for (unsigned i=0; i<ctx.stp_module_index; i++)
+ ctx->output << "\n";
+ ctx->output << "static struct _stp_module *_stp_modules [] = {\n";
+ for (unsigned i=0; i<ctx->stp_module_index; i++)
{
- kallsyms_out << "& _stp_module_" << i << ",\n";
+ ctx->output << "& _stp_module_" << i << ",\n";
}
- kallsyms_out << "};\n";
- kallsyms_out << "static unsigned _stp_num_modules = " << ctx.stp_module_index << ";\n";
+ ctx->output << "};\n";
+ ctx->output << "static unsigned _stp_num_modules = " << ctx->stp_module_index << ";\n";
// Some nonexistent modules may have been identified with "-d". Note them.
- for (set<string>::iterator it = ctx.undone_unwindsym_modules.begin();
- it != ctx.undone_unwindsym_modules.end();
+ for (set<string>::iterator it = ctx->undone_unwindsym_modules.begin();
+ it != ctx->undone_unwindsym_modules.end();
it ++)
{
s.print_warning ("missing unwind/symbol data for module '" + (*it) + "'");
s.op->newline() << "#ifndef MINSTACKSPACE";
s.op->newline() << "#define MINSTACKSPACE 1024";
s.op->newline() << "#endif";
+ s.op->newline() << "#ifndef INTERRUPTIBLE";
+ s.op->newline() << "#define INTERRUPTIBLE 1";
+ s.op->newline() << "#endif";
// Overload processing
s.op->newline() << "#ifndef STP_OVERLOAD_INTERVAL";
s.op->newline() << "#define STP_OVERLOAD";
s.op->newline() << "#endif";
+ s.op->newline() << "#define STP_SKIP_BADVARS " << (s.skip_badvars ? 1 : 0);
+
if (s.bulk_mode)
s.op->newline() << "#define STP_BULKMODE";
s.op->newline() << "#define STP_PERFMON";
s.op->newline() << "#include \"runtime.h\"";
- s.op->newline() << "#include \"regs.c\"";
s.op->newline() << "#include \"stack.c\"";
- s.op->newline() << "#include \"regs-ia64.c\"";
s.op->newline() << "#include \"stat.c\"";
s.op->newline() << "#include <linux/string.h>";
s.op->newline() << "#include <linux/timer.h>";
s.op->newline() << s.embeds[i]->code << "\n";
}
- s.op->newline() << "static struct {";
- s.op->indent(1);
- for (unsigned i=0; i<s.globals.size(); i++)
- {
- s.up->emit_global (s.globals[i]);
- }
- s.op->newline(-1) << "} global = {";
- s.op->newline(1);
- for (unsigned i=0; i<s.globals.size(); i++)
- {
- if (pending_interrupts) return 1;
- s.up->emit_global_init (s.globals[i]);
- }
- s.op->newline(-1) << "};";
- s.op->assert_0_indent();
+ if (s.globals.size()>0) {
+ s.op->newline() << "static struct {";
+ s.op->indent(1);
+ for (unsigned i=0; i<s.globals.size(); i++)
+ {
+ s.up->emit_global (s.globals[i]);
+ }
+ s.op->newline(-1) << "} global = {";
+ s.op->newline(1);
+ for (unsigned i=0; i<s.globals.size(); i++)
+ {
+ if (pending_interrupts) return 1;
+ s.up->emit_global_init (s.globals[i]);
+ }
+ s.op->newline(-1) << "};";
+ s.op->assert_0_indent();
+ }
for (map<string,functiondecl*>::iterator it = s.functions.begin(); it != s.functions.end(); it++)
{
}
s.op->assert_0_indent();
+ s.op->newline();
+ s.up->emit_unprivileged_user_check ();
+ s.op->assert_0_indent();
s.op->newline();
s.up->emit_module_init ();
s.op->assert_0_indent();
s.op->newline();
// XXX impedance mismatch
- s.op->newline() << "static int probe_start () {";
+ s.op->newline() << "static int probe_start (void) {";
s.op->newline(1) << "return systemtap_module_init () ? -1 : 0;";
s.op->newline(-1) << "}";
s.op->newline();
- s.op->newline() << "static void probe_exit () {";
+ s.op->newline() << "static void probe_exit (void) {";
s.op->newline(1) << "systemtap_module_exit ();";
s.op->newline(-1) << "}";
s.op->assert_0_indent();
git://sourceware.org / systemtap.git / blobdiff