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go.mod: github.com/opencontainers/runc v1.1.0

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Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>
This commit is contained in:
Akihiro Suda
2022-01-18 13:35:22 +09:00
parent dba897c35c
commit 21a748e381
93 changed files with 2416 additions and 2617 deletions
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135
vendor/github.com/cilium/ebpf/link/uprobe.go generated vendored
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@@ -25,14 +25,18 @@ var (
value uint64
err error
}{}
// ErrNoSymbol indicates that the given symbol was not found
// in the ELF symbols table.
ErrNoSymbol = errors.New("not found")
)
// Executable defines an executable program on the filesystem.
type Executable struct {
// Path of the executable on the filesystem.
path string
// Parsed ELF symbols and dynamic symbols.
symbols map[string]elf.Symbol
// Parsed ELF symbols and dynamic symbols offsets.
offsets map[string]uint64
}
// UprobeOptions defines additional parameters that will be used
@@ -41,6 +45,9 @@ type UprobeOptions struct {
// Symbol offset. Must be provided in case of external symbols (shared libs).
// If set, overrides the offset eventually parsed from the executable.
Offset uint64
// Only set the uprobe on the given process ID. Useful when tracing
// shared library calls or programs that have many running instances.
PID int
}
// To open a new Executable, use:
@@ -64,42 +71,84 @@ func OpenExecutable(path string) (*Executable, error) {
return nil, fmt.Errorf("parse ELF file: %w", err)
}
var ex = Executable{
path: path,
symbols: make(map[string]elf.Symbol),
}
if err := ex.addSymbols(se.Symbols); err != nil {
return nil, err
if se.Type != elf.ET_EXEC && se.Type != elf.ET_DYN {
// ELF is not an executable or a shared object.
return nil, errors.New("the given file is not an executable or a shared object")
}
if err := ex.addSymbols(se.DynamicSymbols); err != nil {
ex := Executable{
path: path,
offsets: make(map[string]uint64),
}
if err := ex.load(se); err != nil {
return nil, err
}
return &ex, nil
}
func (ex *Executable) addSymbols(f func() ([]elf.Symbol, error)) error {
// elf.Symbols and elf.DynamicSymbols return ErrNoSymbols if the section is not found.
syms, err := f()
func (ex *Executable) load(f *internal.SafeELFFile) error {
syms, err := f.Symbols()
if err != nil && !errors.Is(err, elf.ErrNoSymbols) {
return err
}
dynsyms, err := f.DynamicSymbols()
if err != nil && !errors.Is(err, elf.ErrNoSymbols) {
return err
}
syms = append(syms, dynsyms...)
for _, s := range syms {
if elf.ST_TYPE(s.Info) != elf.STT_FUNC {
// Symbol not associated with a function or other executable code.
continue
}
ex.symbols[s.Name] = s
off := s.Value
// Loop over ELF segments.
for _, prog := range f.Progs {
// Skip uninteresting segments.
if prog.Type != elf.PT_LOAD || (prog.Flags&elf.PF_X) == 0 {
continue
}
if prog.Vaddr <= s.Value && s.Value < (prog.Vaddr+prog.Memsz) {
// If the symbol value is contained in the segment, calculate
// the symbol offset.
//
// fn symbol offset = fn symbol VA - .text VA + .text offset
//
// stackoverflow.com/a/40249502
off = s.Value - prog.Vaddr + prog.Off
break
}
}
ex.offsets[s.Name] = off
}
return nil
}
func (ex *Executable) symbol(symbol string) (*elf.Symbol, error) {
if s, ok := ex.symbols[symbol]; ok {
return &s, nil
func (ex *Executable) offset(symbol string) (uint64, error) {
if off, ok := ex.offsets[symbol]; ok {
// Symbols with location 0 from section undef are shared library calls and
// are relocated before the binary is executed. Dynamic linking is not
// implemented by the library, so mark this as unsupported for now.
//
// Since only offset values are stored and not elf.Symbol, if the value is 0,
// assume it's an external symbol.
if off == 0 {
return 0, fmt.Errorf("cannot resolve %s library call '%s', "+
"consider providing the offset via options: %w", ex.path, symbol, ErrNotSupported)
}
return off, nil
}
return nil, fmt.Errorf("symbol %s not found", symbol)
return 0, fmt.Errorf("symbol %s: %w", symbol, ErrNoSymbol)
}
// Uprobe attaches the given eBPF program to a perf event that fires when the
@@ -112,11 +161,14 @@ func (ex *Executable) symbol(symbol string) (*elf.Symbol, error) {
// When using symbols which belongs to shared libraries,
// an offset must be provided via options:
//
// ex.Uprobe("main", prog, &UprobeOptions{Offset: 0x123})
// up, err := ex.Uprobe("main", prog, &UprobeOptions{Offset: 0x123})
//
// The resulting Link must be Closed during program shutdown to avoid leaking
// system resources. Functions provided by shared libraries can currently not
// be traced and will result in an ErrNotSupported.
// Losing the reference to the resulting Link (up) will close the Uprobe
// and prevent further execution of prog. The Link must be Closed during
// program shutdown to avoid leaking system resources.
//
// Functions provided by shared libraries can currently not be traced and
// will result in an ErrNotSupported.
func (ex *Executable) Uprobe(symbol string, prog *ebpf.Program, opts *UprobeOptions) (Link, error) {
u, err := ex.uprobe(symbol, prog, opts, false)
if err != nil {
@@ -141,11 +193,14 @@ func (ex *Executable) Uprobe(symbol string, prog *ebpf.Program, opts *UprobeOpti
// When using symbols which belongs to shared libraries,
// an offset must be provided via options:
//
// ex.Uretprobe("main", prog, &UprobeOptions{Offset: 0x123})
// up, err := ex.Uretprobe("main", prog, &UprobeOptions{Offset: 0x123})
//
// The resulting Link must be Closed during program shutdown to avoid leaking
// system resources. Functions provided by shared libraries can currently not
// be traced and will result in an ErrNotSupported.
// Losing the reference to the resulting Link (up) will close the Uprobe
// and prevent further execution of prog. The Link must be Closed during
// program shutdown to avoid leaking system resources.
//
// Functions provided by shared libraries can currently not be traced and
// will result in an ErrNotSupported.
func (ex *Executable) Uretprobe(symbol string, prog *ebpf.Program, opts *UprobeOptions) (Link, error) {
u, err := ex.uprobe(symbol, prog, opts, true)
if err != nil {
@@ -175,24 +230,20 @@ func (ex *Executable) uprobe(symbol string, prog *ebpf.Program, opts *UprobeOpti
if opts != nil && opts.Offset != 0 {
offset = opts.Offset
} else {
sym, err := ex.symbol(symbol)
off, err := ex.offset(symbol)
if err != nil {
return nil, fmt.Errorf("symbol '%s' not found: %w", symbol, err)
return nil, err
}
offset = off
}
// Symbols with location 0 from section undef are shared library calls and
// are relocated before the binary is executed. Dynamic linking is not
// implemented by the library, so mark this as unsupported for now.
if sym.Section == elf.SHN_UNDEF && sym.Value == 0 {
return nil, fmt.Errorf("cannot resolve %s library call '%s', "+
"consider providing the offset via options: %w", ex.path, symbol, ErrNotSupported)
}
offset = sym.Value
pid := perfAllThreads
if opts != nil && opts.PID != 0 {
pid = opts.PID
}
// Use uprobe PMU if the kernel has it available.
tp, err := pmuUprobe(symbol, ex.path, offset, ret)
tp, err := pmuUprobe(symbol, ex.path, offset, pid, ret)
if err == nil {
return tp, nil
}
@@ -201,7 +252,7 @@ func (ex *Executable) uprobe(symbol string, prog *ebpf.Program, opts *UprobeOpti
}
// Use tracefs if uprobe PMU is missing.
tp, err = tracefsUprobe(uprobeSanitizedSymbol(symbol), ex.path, offset, ret)
tp, err = tracefsUprobe(uprobeSanitizedSymbol(symbol), ex.path, offset, pid, ret)
if err != nil {
return nil, fmt.Errorf("creating trace event '%s:%s' in tracefs: %w", ex.path, symbol, err)
}
@@ -210,13 +261,13 @@ func (ex *Executable) uprobe(symbol string, prog *ebpf.Program, opts *UprobeOpti
}
// pmuUprobe opens a perf event based on the uprobe PMU.
func pmuUprobe(symbol, path string, offset uint64, ret bool) (*perfEvent, error) {
return pmuProbe(uprobeType, symbol, path, offset, ret)
func pmuUprobe(symbol, path string, offset uint64, pid int, ret bool) (*perfEvent, error) {
return pmuProbe(uprobeType, symbol, path, offset, pid, ret)
}
// tracefsUprobe creates a Uprobe tracefs entry.
func tracefsUprobe(symbol, path string, offset uint64, ret bool) (*perfEvent, error) {
return tracefsProbe(uprobeType, symbol, path, offset, ret)
func tracefsUprobe(symbol, path string, offset uint64, pid int, ret bool) (*perfEvent, error) {
return tracefsProbe(uprobeType, symbol, path, offset, pid, ret)
}
// uprobeSanitizedSymbol replaces every invalid characted for the tracefs api with an underscore.