libzypp  17.31.27
CheckAccessDeleted.cc
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1 /*---------------------------------------------------------------------\
2 | ____ _ __ __ ___ |
3 | |__ / \ / / . \ . \ |
4 | / / \ V /| _/ _/ |
5 | / /__ | | | | | | |
6 | /_____||_| |_| |_| |
7 | |
8 \---------------------------------------------------------------------*/
12 #include <iostream>
13 #include <fstream>
14 #include <unordered_set>
15 #include <iterator>
16 #include <stdio.h>
17 #include <zypp/base/LogControl.h>
18 #include <zypp/base/LogTools.h>
19 #include <zypp/base/String.h>
20 #include <zypp/base/Gettext.h>
21 #include <zypp/base/Exception.h>
22 
23 #include <zypp/PathInfo.h>
24 #include <zypp/ExternalProgram.h>
25 #include <zypp/base/Regex.h>
26 #include <zypp/base/IOStream.h>
27 #include <zypp-core/base/InputStream>
29 
31 
32 using std::endl;
33 
34 #undef ZYPP_BASE_LOGGER_LOGGROUP
35 #define ZYPP_BASE_LOGGER_LOGGROUP "zypp::misc"
36 
38 namespace zypp
39 {
40 
42  namespace
43  {
44  //
45  // lsof output lines are a sequence of NUL terminated fields,
46  // where the 1st char determines the fields type.
47  //
48  // (pcuL) pid command userid loginname
49  // (ftkn).filedescriptor type linkcount filename
50  //
52 
54  typedef std::pair<std::string,std::unordered_set<std::string>> CacheEntry;
55 
62  struct FilterRunsInContainer
63  {
64  private:
65 
66  enum Type {
67  IGNORE,
68  HOST,
69  CONTAINER
70  };
71 
77  Type in_our_root( const Pathname &path ) const {
78 
79  const PathInfo procInfoStat( path );
80 
81  // if we can not stat the file continue to the next one
82  if ( procInfoStat.error() ) return IGNORE;
83 
84  // if the file was unlinked ignore it
85  if ( procInfoStat.nlink() == 0 )
86  return IGNORE;
87 
88  // get the file the link points to, if that fails continue to the next
89  const Pathname linkTarget = filesystem::readlink( path );
90  if ( linkTarget.empty() ) return IGNORE;
91 
92  // get stat info for the target file
93  const PathInfo linkStat( linkTarget );
94 
95  // Non-existent path could be anything. Pipe or socket (type:[inode])
96  // or an 'anon_inode:<file-type>'. (bsc#1218291)
97  if ( !linkStat.isExist() )
98  return IGNORE;
99 
100  // If the file exists, it could simply mean it exists in and outside a container, check inode to be safe
101  if ( linkStat.ino() != procInfoStat.ino())
102  return CONTAINER;
103 
104  // If the inode is the same, it could simply mean it exists in and outside a container but on different devices, check to be safe
105  if ( linkStat.dev() != procInfoStat.dev() )
106  return CONTAINER;
107 
108  // assume HOST if all tests fail
109  return HOST;
110  }
111 
112  public:
113 
117  bool operator()( const pid_t pid ) const {
118 
119  // first check the exe file
120  const Pathname pidDir = Pathname("/proc") / asString(pid);
121  const Pathname exeFile = pidDir / "exe";
122 
123  auto res = in_our_root( exeFile );
124  if ( res > IGNORE )
125  return res == CONTAINER;
126 
127  // if IGNORE was returned we need to continue testing all the files in /proc/<pid>/map_files until we hopefully
128  // find a still existing file. If all tests fail we will simply assume this pid is running on the HOST
129 
130  // a map of all already tested files, each file can be mapped multiple times and we do not want to check them more than once
131  std::unordered_set<std::string> tested;
132 
133  // iterate over all the entries in /proc/<pid>/map_files
134  filesystem::dirForEach( pidDir / "map_files", [ this, &tested, &res ]( const Pathname & dir_r, const char *const & name_r ){
135 
136  // some helpers to make the code more self explanatory
137  constexpr bool contloop = true;
138  constexpr bool stoploop = false;
139 
140  const Pathname entryName = dir_r / name_r;
141 
142  // get the links target file and check if we alreadys know it, also if we can not read link information we skip the file
143  const Pathname linkTarget = filesystem::readlink( entryName );
144  if ( linkTarget.empty() || !tested.insert( linkTarget.asString() ).second ) return contloop;
145 
146  // try to get file type
147  const auto mappedFileType = in_our_root( entryName );
148 
149  // if we got something, remember the value and stop the loop
150  if ( mappedFileType > IGNORE ) {
151  res = mappedFileType;
152  return stoploop;
153  }
154  return contloop;
155  });
156 
157  // If res is still IGNORE, we did not find a explicit answer. So, to be safe, we assume it is running on the host.
158  if ( res == IGNORE )
159  return false; // can't tell for sure, lets assume host
160 
161  return res == CONTAINER;
162  }
163 
164  FilterRunsInContainer() {}
165  };
166 
167 
173  bool lsofNoOptKi()
174  {
175  using target::rpm::librpmDb;
176  // RpmDb access is blocked while the Target is not initialized.
177  // Launching the Target just for this query would be an overkill.
178  struct TmpUnblock {
179  TmpUnblock()
180  : _wasBlocked( librpmDb::isBlocked() )
181  { if ( _wasBlocked ) librpmDb::unblockAccess(); }
182  ~TmpUnblock()
183  { if ( _wasBlocked ) librpmDb::blockAccess(); }
184  private:
185  bool _wasBlocked;
186  } tmpUnblock;
187 
188  librpmDb::db_const_iterator it;
189  return( it.findPackage( "lsof" ) && it->tag_edition() < Edition("4.90") && !it->tag_provides().count( Capability("backported-option-Ki") ) );
190  }
191 
192  } //namespace
194 
196  {
197  public:
199 
200  bool addDataIf( const CacheEntry & cache_r, std::vector<std::string> *debMap = nullptr );
201  void addCacheIf( CacheEntry & cache_r, const std::string & line_r, std::vector<std::string> *debMap = nullptr );
202 
203  std::map<pid_t,CacheEntry> filterInput( externalprogram::ExternalDataSource &source );
204  CheckAccessDeleted::size_type createProcInfo( const std::map<pid_t,CacheEntry> &in );
205 
206  std::vector<CheckAccessDeleted::ProcInfo> _data;
207  bool _fromLsofFileMode = false; // Set if we currently process data from a debug file
208  bool _verbose = false;
209 
210  std::map<pid_t,std::vector<std::string>> debugMap; //will contain all used lsof files after filtering
212  };
213 
215  {
216  Impl *myClone = new Impl( *this );
217  return myClone;
218  }
219 
224  inline bool CheckAccessDeleted::Impl::addDataIf( const CacheEntry & cache_r, std::vector<std::string> *debMap )
225  {
226  const auto & filelist( cache_r.second );
227 
228  if ( filelist.empty() )
229  return false;
230 
231  // at least one file access so keep it:
232  _data.push_back( CheckAccessDeleted::ProcInfo() );
233  CheckAccessDeleted::ProcInfo & pinfo( _data.back() );
234  pinfo.files.insert( pinfo.files.begin(), filelist.begin(), filelist.end() );
235 
236  const std::string & pline( cache_r.first );
237  std::string commandname; // pinfo.command if still needed...
238  std::ostringstream pLineStr; //rewrite the first line in debug cache
239  for_( ch, pline.begin(), pline.end() )
240  {
241  switch ( *ch )
242  {
243  case 'p':
244  pinfo.pid = &*(ch+1);
245  if ( debMap )
246  pLineStr <<&*(ch)<<'\0';
247  break;
248  case 'R':
249  pinfo.ppid = &*(ch+1);
250  if ( debMap )
251  pLineStr <<&*(ch)<<'\0';
252  break;
253  case 'u':
254  pinfo.puid = &*(ch+1);
255  if ( debMap )
256  pLineStr <<&*(ch)<<'\0';
257  break;
258  case 'L':
259  pinfo.login = &*(ch+1);
260  if ( debMap )
261  pLineStr <<&*(ch)<<'\0';
262  break;
263  case 'c':
264  if ( pinfo.command.empty() ) {
265  commandname = &*(ch+1);
266  // the lsof command name might be truncated, so we prefer /proc/<pid>/exe
267  if (!_fromLsofFileMode)
268  pinfo.command = filesystem::readlink( Pathname("/proc")/pinfo.pid/"exe" ).basename();
269  if ( pinfo.command.empty() )
270  pinfo.command = std::move(commandname);
271  if ( debMap )
272  pLineStr <<'c'<<pinfo.command<<'\0';
273  }
274  break;
275  }
276  if ( *ch == '\n' ) break; // end of data
277  do { ++ch; } while ( *ch != '\0' ); // skip to next field
278  }
279 
280  //replace the data in the debug cache as well
281  if ( debMap ) {
282  pLineStr<<endl;
283  debMap->front() = pLineStr.str();
284  }
285 
286  //entry was added
287  return true;
288  }
289 
290 
296  inline void CheckAccessDeleted::Impl::addCacheIf( CacheEntry & cache_r, const std::string & line_r, std::vector<std::string> *debMap )
297  {
298  const char * f = 0;
299  const char * t = 0;
300  const char * n = 0;
301 
302  for_( ch, line_r.c_str(), ch+line_r.size() )
303  {
304  switch ( *ch )
305  {
306  case 'k':
307  if ( *(ch+1) != '0' ) // skip non-zero link counts
308  return;
309  break;
310  case 'f':
311  f = ch+1;
312  break;
313  case 't':
314  t = ch+1;
315  break;
316  case 'n':
317  n = ch+1;
318  break;
319  }
320  if ( *ch == '\n' ) break; // end of data
321  do { ++ch; } while ( *ch != '\0' ); // skip to next field
322  }
323 
324  if ( !t || !f || !n )
325  return; // wrong filedescriptor/type/name
326 
327  if ( !( ( *t == 'R' && *(t+1) == 'E' && *(t+2) == 'G' && *(t+3) == '\0' )
328  || ( *t == 'D' && *(t+1) == 'E' && *(t+2) == 'L' && *(t+3) == '\0' ) ) )
329  return; // wrong type
330 
331  if ( !( ( *f == 'm' && *(f+1) == 'e' && *(f+2) == 'm' && *(f+3) == '\0' )
332  || ( *f == 't' && *(f+1) == 'x' && *(f+2) == 't' && *(f+3) == '\0' )
333  || ( *f == 'D' && *(f+1) == 'E' && *(f+2) == 'L' && *(f+3) == '\0' )
334  || ( *f == 'l' && *(f+1) == 't' && *(f+2) == 'x' && *(f+3) == '\0' ) ) )
335  return; // wrong filedescriptor type
336 
337  if ( str::contains( n, "(stat: Permission denied)" ) )
338  return; // Avoid reporting false positive due to insufficient permission.
339 
340  if ( ! _verbose )
341  {
342  if ( ! ( str::contains( n, "/lib" ) || str::contains( n, "bin/" ) ) )
343  return; // Try to avoid reporting false positive unless verbose.
344  }
345 
346  if ( *f == 'm' || *f == 'D' ) // skip some wellknown nonlibrary memorymapped files
347  {
348  static const char * black[] = {
349  "/SYSV"
350  , "/var/"
351  , "/dev/"
352  , "/tmp/"
353  , "/proc/"
354  , "/memfd:"
355  };
356  for_( it, arrayBegin( black ), arrayEnd( black ) )
357  {
358  if ( str::hasPrefix( n, *it ) )
359  return;
360  }
361  }
362  // Add if no duplicate
363  if ( debMap && cache_r.second.find(n) == cache_r.second.end() ) {
364  debMap->push_back(line_r);
365  }
366  cache_r.second.insert( n );
367  }
368 
370  : _pimpl(new Impl)
371  {
372  if ( doCheck_r ) check();
373  }
374 
375  CheckAccessDeleted::size_type CheckAccessDeleted::check( const Pathname &lsofOutput_r, bool verbose_r )
376  {
377  _pimpl->_verbose = verbose_r;
378  _pimpl->_fromLsofFileMode = true;
379 
380  FILE *inFile = fopen( lsofOutput_r.c_str(), "r" );
381  if ( !inFile ) {
382  ZYPP_THROW( Exception( str::Format("Opening input file %1% failed.") % lsofOutput_r.c_str() ) );
383  }
384 
385  //inFile is closed by ExternalDataSource
386  externalprogram::ExternalDataSource inSource( inFile, nullptr );
387  auto cache = _pimpl->filterInput( inSource );
388  return _pimpl->createProcInfo( cache );
389  }
390 
392  {
393  // cachemap: PID => (deleted files)
394  // NOTE: omit PIDs running in a (lxc/docker) container
395  std::map<pid_t,CacheEntry> cachemap;
396 
397  bool debugEnabled = !_debugFile.empty();
398 
399  pid_t cachepid = 0;
400  FilterRunsInContainer runsInLXC;
401  MIL << "Silently scanning lsof output..." << endl;
402  zypp::base::LogControl::TmpLineWriter shutUp; // suppress excessive readdir etc. logging in runsInLXC
403  for( std::string line = source.receiveLine( 30 * 1000 ); ! line.empty(); line = source.receiveLine( 30 * 1000 ) )
404  {
405  // NOTE: line contains '\0' separeated fields!
406  if ( line[0] == 'p' )
407  {
408  str::strtonum( line.c_str()+1, cachepid ); // line is "p<PID>\0...."
409  if ( _fromLsofFileMode || !runsInLXC( cachepid ) ) {
410  if ( debugEnabled ) {
411  auto &pidMad = debugMap[cachepid];
412  if ( pidMad.empty() )
413  debugMap[cachepid].push_back( line );
414  else
415  debugMap[cachepid].front() = line;
416  }
417  cachemap[cachepid].first.swap( line );
418  } else {
419  cachepid = 0; // ignore this pid
420  }
421  }
422  else if ( cachepid )
423  {
424  auto &dbgMap = debugMap[cachepid];
425  addCacheIf( cachemap[cachepid], line, debugEnabled ? &dbgMap : nullptr);
426  }
427  }
428  return cachemap;
429  }
430 
432  {
433  static const char* argv[] = { "lsof", "-n", "-FpcuLRftkn0", "-K", "i", NULL };
434  if ( lsofNoOptKi() )
435  argv[3] = NULL;
436 
437  _pimpl->_verbose = verbose_r;
438  _pimpl->_fromLsofFileMode = false;
439 
441  std::map<pid_t,CacheEntry> cachemap;
442 
443  try {
444  cachemap = _pimpl->filterInput( prog );
445  } catch ( const io::TimeoutException &e ) {
446  ZYPP_CAUGHT( e );
447  prog.kill();
448  ZYPP_THROW ( Exception( "Reading data from 'lsof' timed out.") );
449  }
450 
451  int ret = prog.close();
452  if ( ret != 0 )
453  {
454  if ( ret == 129 )
455  {
456  ZYPP_THROW( Exception(_("Please install package 'lsof' first.") ) );
457  }
458  Exception err( str::Format("Executing 'lsof' failed (%1%).") % ret );
459  err.remember( prog.execError() );
460  ZYPP_THROW( err );
461  }
462 
463  return _pimpl->createProcInfo( cachemap );
464  }
465 
467  {
468  std::ofstream debugFileOut;
469  bool debugEnabled = false;
470  if ( !_debugFile.empty() ) {
471  debugFileOut.open( _debugFile.c_str() );
472  debugEnabled = debugFileOut.is_open();
473 
474  if ( !debugEnabled ) {
475  ERR<<"Unable to open debug file: "<<_debugFile<<endl;
476  }
477  }
478 
479  _data.clear();
480  for ( const auto &cached : in )
481  {
482  if (!debugEnabled)
483  addDataIf( cached.second);
484  else {
485  std::vector<std::string> *mapPtr = nullptr;
486 
487  auto dbgInfo = debugMap.find(cached.first);
488  if ( dbgInfo != debugMap.end() )
489  mapPtr = &(dbgInfo->second);
490 
491  if( !addDataIf( cached.second, mapPtr ) )
492  continue;
493 
494  for ( const std::string &dbgLine: dbgInfo->second ) {
495  debugFileOut.write( dbgLine.c_str(), dbgLine.length() );
496  }
497  }
498  }
499  return _data.size();
500  }
501 
503  {
504  return _pimpl->_data.empty();
505  }
506 
508  {
509  return _pimpl->_data.size();
510  }
511 
513  {
514  return _pimpl->_data.begin();
515  }
516 
518  {
519  return _pimpl->_data.end();
520  }
521 
523  {
524  _pimpl->_debugFile = filename_r;
525  }
526 
527  std::string CheckAccessDeleted::findService( pid_t pid_r )
528  {
529  ProcInfo p;
530  p.pid = str::numstring( pid_r );
531  return p.service();
532  }
533 
535  {
536  // cgroup entries like:
537  // 1:name=systemd:/system.slice/systemd-udevd.service
538  // 0::/system.slice/systemd-udevd.service
539  // 0::/system.slice/systemd-udevd.service/udev
540  static const str::regex rx( "(0::|[0-9]+:name=systemd:)/system.slice/(.*/)?(.*).service(/.*)?$" );
541  str::smatch what;
542  std::string ret;
543  iostr::simpleParseFile( InputStream( Pathname("/proc")/pid/"cgroup" ),
544  [&]( int num_r, std::string line_r )->bool
545  {
546  if ( str::regex_match( line_r, what, rx ) )
547  {
548  ret = what[3];
549  return false; // stop after match
550  }
551  return true;
552  } );
553  return ret;
554  }
555 
556  /******************************************************************
557  **
558  ** FUNCTION NAME : operator<<
559  ** FUNCTION TYPE : std::ostream &
560  */
561  std::ostream & operator<<( std::ostream & str, const CheckAccessDeleted & obj )
562  {
563  return dumpRange( str << "CheckAccessDeleted ",
564  obj.begin(),
565  obj.end() );
566  }
567 
568  /******************************************************************
569  **
570  ** FUNCTION NAME : operator<<
571  ** FUNCTION TYPE : std::ostream &
572  */
573  std::ostream & operator<<( std::ostream & str, const CheckAccessDeleted::ProcInfo & obj )
574  {
575  if ( obj.pid.empty() )
576  return str << "<NoProc>";
577 
578  return dumpRangeLine( str << obj.command
579  << '<' << obj.pid
580  << '|' << obj.ppid
581  << '|' << obj.puid
582  << '|' << obj.login
583  << '>',
584  obj.files.begin(),
585  obj.files.end() );
586  }
587 
589 } // namespace zypp
std::string asString(const Patch::Category &obj)
Definition: Patch.cc:122
bool addDataIf(const CacheEntry &cache_r, std::vector< std::string > *debMap=nullptr)
Add cache to data if the process is accessing deleted files.
Data about one running process accessing deleted files.
#define MIL
Definition: Logger.h:96
Bidirectional stream to external data.
bool contains(const C_Str &str_r, const C_Str &val_r)
Locate substring case sensitive.
Definition: String.h:991
std::map< pid_t, CacheEntry > filterInput(externalprogram::ExternalDataSource &source)
#define _(MSG)
Definition: Gettext.h:37
#define ZYPP_THROW(EXCPT)
Drops a logline and throws the Exception.
Definition: Exception.h:428
Regular expression.
Definition: Regex.h:94
bool kill()
Kill the program.
std::map< pid_t, std::vector< std::string > > debugMap
int readlink(const Pathname &symlink_r, Pathname &target_r)
Like &#39;readlink&#39;.
Definition: PathInfo.cc:924
void setDebugOutputFile(const Pathname &filename_r)
Writes all filtered process entries that make it into the final set into a file specified by filename...
const std::string & execError() const
Some detail telling why the execution failed, if it failed.
std::ostream & dumpRange(std::ostream &str, TIterator begin, TIterator end, const std::string &intro="{", const std::string &pfx="\ ", const std::string &sep="\ ", const std::string &sfx="\, const std::string &extro="}")
Print range defined by iterators (multiline style).
Definition: LogTools.h:92
int dirForEach(const Pathname &dir_r, const StrMatcher &matcher_r, function< bool(const Pathname &, const char *const)> fnc_r)
Definition: PathInfo.cc:32
#define for_(IT, BEG, END)
Convenient for-loops using iterator.
Definition: Easy.h:28
const char * c_str() const
String representation.
Definition: Pathname.h:110
std::string command
process command name
String related utilities and Regular expression matching.
Helper to create and pass std::istream.
Definition: inputstream.h:56
std::string receiveLine()
Read one line from the input stream.
Convenient building of std::string with boost::format.
Definition: String.h:252
Exchange LineWriter for the lifetime of this object.
Definition: LogControl.h:190
std::ostream & operator<<(std::ostream &str, const CheckAccessDeleted &obj)
#define ERR
Definition: Logger.h:98
void remember(const Exception &old_r)
Store an other Exception as history.
Definition: Exception.cc:105
CheckAccessDeleted::Impl * clone() const
bool empty() const
Test for an empty path.
Definition: Pathname.h:114
size_type check(bool verbose_r=false)
Check for running processes which access deleted executables or libraries.
RWCOW_pointer< Impl > _pimpl
const_iterator begin() const
int simpleParseFile(std::istream &str_r, ParseFlags flags_r, function< bool(int, std::string)> consume_r)
Simple lineparser optionally trimming and skipping comments.
Definition: IOStream.cc:124
Execute a program and give access to its io An object of this class encapsulates the execution of an ...
std::list< PublicKeyData > _data
Definition: KeyRing.cc:191
std::vector< CheckAccessDeleted::ProcInfo > _data
TInt strtonum(const C_Str &str)
Parsing numbers from string.
Definition: String.h:388
std::string puid
process user ID
const_iterator end() const
std::string numstring(char n, int w=0)
Definition: String.h:289
CheckAccessDeleted::size_type createProcInfo(const std::map< pid_t, CacheEntry > &in)
#define arrayEnd(A)
Definition: Easy.h:43
int close()
Wait for the progamm to complete.
#define ZYPP_CAUGHT(EXCPT)
Drops a logline telling the Exception was caught (in order to handle it).
Definition: Exception.h:436
Regular expression match result.
Definition: Regex.h:167
Base class for Exception.
Definition: Exception.h:145
Check for running processes which access deleted executables or libraries.
CheckAccessDeleted(bool doCheck_r=true)
Default ctor performs check immediately.
std::ostream & dumpRangeLine(std::ostream &str, TIterator begin, TIterator end)
Print range defined by iterators (single line style).
Definition: LogTools.h:115
bool regex_match(const std::string &s, smatch &matches, const regex &regex)
regex ZYPP_STR_REGEX regex ZYPP_STR_REGEX
Definition: Regex.h:70
Easy-to use interface to the ZYPP dependency resolver.
Definition: CodePitfalls.doc:1
bool hasPrefix(const C_Str &str_r, const C_Str &prefix_r)
Return whether str_r has prefix prefix_r.
Definition: String.h:1027
std::vector< ProcInfo >::const_iterator const_iterator
std::string login
process login name
void addCacheIf(CacheEntry &cache_r, const std::string &line_r, std::vector< std::string > *debMap=nullptr)
Add file to cache if it refers to a deleted executable or library file:
std::vector< std::string > files
list of deleted executables or libraries accessed
#define arrayBegin(A)
Simple C-array iterator.
Definition: Easy.h:41
std::string ppid
parent process ID
std::string service() const
Guess if command was started by a systemd service script.
static std::string findService(pid_t pid_r)
Guess if pid was started by a systemd service script.