libzypp 17.35.1
CheckAccessDeleted.cc
Go to the documentation of this file.
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>
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>
25#include <zypp/base/Regex.h>
26#include <zypp/base/IOStream.h>
27#include <zypp-core/base/InputStream>
29
31
32using std::endl;
33
34#undef ZYPP_BASE_LOGGER_LOGGROUP
35#define ZYPP_BASE_LOGGER_LOGGROUP "zypp::misc"
36
38namespace 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 using CacheEntry = std::pair<std::string, std::unordered_set<std::string>>;
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 // Pipe or socket 'type:[inode]' or an 'anon_inode:<file-type>'
93 // They may or may not belong to a container... (bsc#1218291)
94 if ( linkTarget.relative() ) return IGNORE;
95
96 // get stat info for the target file
97 const PathInfo linkStat( linkTarget );
98
99 // Non-existent path means it's not reachable by us.
100 if ( !linkStat.isExist() )
101 return CONTAINER;
102
103 // If the file exists, it could simply mean it exists in and outside a container, check inode to be safe
104 if ( linkStat.ino() != procInfoStat.ino())
105 return CONTAINER;
106
107 // 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
108 if ( linkStat.dev() != procInfoStat.dev() )
109 return CONTAINER;
110
111 // assume HOST if all tests fail
112 return HOST;
113 }
114
115 public:
116
120 bool operator()( const pid_t pid ) const {
121
122 // first check the exe file
123 const Pathname pidDir = Pathname("/proc") / asString(pid);
124 const Pathname exeFile = pidDir / "exe";
125
126 auto res = in_our_root( exeFile );
127 if ( res > IGNORE )
128 return res == CONTAINER;
129
130 // if IGNORE was returned we need to continue testing all the files in /proc/<pid>/map_files until we hopefully
131 // find a still existing file. If all tests fail we will simply assume this pid is running on the HOST
132
133 // 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
134 std::unordered_set<std::string> tested;
135
136 // iterate over all the entries in /proc/<pid>/map_files
137 filesystem::dirForEach( pidDir / "map_files", [ this, &tested, &res ]( const Pathname & dir_r, const char *const & name_r ){
138
139 // some helpers to make the code more self explanatory
140 constexpr bool contloop = true;
141 constexpr bool stoploop = false;
142
143 const Pathname entryName = dir_r / name_r;
144
145 // get the links target file and check if we alreadys know it, also if we can not read link information we skip the file
146 const Pathname linkTarget = filesystem::readlink( entryName );
147 if ( linkTarget.empty() || !tested.insert( linkTarget.asString() ).second ) return contloop;
148
149 // try to get file type
150 const auto mappedFileType = in_our_root( entryName );
151
152 // if we got something, remember the value and stop the loop
153 if ( mappedFileType > IGNORE ) {
154 res = mappedFileType;
155 return stoploop;
156 }
157 return contloop;
158 });
159
160 // If res is still IGNORE, we did not find a explicit answer. So, to be safe, we assume it is running on the host.
161 if ( res == IGNORE )
162 return false; // can't tell for sure, lets assume host
163
164 return res == CONTAINER;
165 }
166
167 FilterRunsInContainer() {}
168 };
169
170
176 bool lsofNoOptKi()
177 {
178 using target::rpm::librpmDb;
179 // RpmDb access is blocked while the Target is not initialized.
180 // Launching the Target just for this query would be an overkill.
181 struct TmpUnblock {
182 TmpUnblock()
183 : _wasBlocked( librpmDb::isBlocked() )
184 { if ( _wasBlocked ) librpmDb::unblockAccess(); }
185 TmpUnblock(const TmpUnblock &) = delete;
186 TmpUnblock(TmpUnblock &&) = delete;
187 TmpUnblock &operator=(const TmpUnblock &) = delete;
188 TmpUnblock &operator=(TmpUnblock &&) = delete;
189 ~TmpUnblock() {
190 if (_wasBlocked)
191 librpmDb::blockAccess();
192 }
193
194 private:
195 bool _wasBlocked;
196 } tmpUnblock;
197
198 librpmDb::db_const_iterator it;
199 return( it.findPackage( "lsof" ) && it->tag_edition() < Edition("4.90") && !it->tag_provides().count( Capability("backported-option-Ki") ) );
200 }
201
202 } //namespace
204
206 {
207 public:
209
210 bool addDataIf( const CacheEntry & cache_r, std::vector<std::string> *debMap = nullptr );
211 void addCacheIf( CacheEntry & cache_r, const std::string & line_r, std::vector<std::string> *debMap = nullptr );
212
213 std::map<pid_t,CacheEntry> filterInput( externalprogram::ExternalDataSource &source );
214 CheckAccessDeleted::size_type createProcInfo( const std::map<pid_t,CacheEntry> &in );
215
216 std::vector<CheckAccessDeleted::ProcInfo> _data;
217 bool _fromLsofFileMode = false; // Set if we currently process data from a debug file
218 bool _verbose = false;
219
220 std::map<pid_t,std::vector<std::string>> debugMap; //will contain all used lsof files after filtering
222 };
223
225 {
226 Impl *myClone = new Impl( *this );
227 return myClone;
228 }
229
234 inline bool CheckAccessDeleted::Impl::addDataIf( const CacheEntry & cache_r, std::vector<std::string> *debMap )
235 {
236 const auto & filelist( cache_r.second );
237
238 if ( filelist.empty() )
239 return false;
240
241 // at least one file access so keep it:
242 _data.push_back( CheckAccessDeleted::ProcInfo() );
243 CheckAccessDeleted::ProcInfo & pinfo( _data.back() );
244 pinfo.files.insert( pinfo.files.begin(), filelist.begin(), filelist.end() );
245
246 const std::string & pline( cache_r.first );
247 std::string commandname; // pinfo.command if still needed...
248 std::ostringstream pLineStr; //rewrite the first line in debug cache
249 for_( ch, pline.begin(), pline.end() )
250 {
251 switch ( *ch )
252 {
253 case 'p':
254 pinfo.pid = &*(ch+1);
255 if ( debMap )
256 pLineStr <<&*(ch)<<'\0';
257 break;
258 case 'R':
259 pinfo.ppid = &*(ch+1);
260 if ( debMap )
261 pLineStr <<&*(ch)<<'\0';
262 break;
263 case 'u':
264 pinfo.puid = &*(ch+1);
265 if ( debMap )
266 pLineStr <<&*(ch)<<'\0';
267 break;
268 case 'L':
269 pinfo.login = &*(ch+1);
270 if ( debMap )
271 pLineStr <<&*(ch)<<'\0';
272 break;
273 case 'c':
274 if ( pinfo.command.empty() ) {
275 commandname = &*(ch+1);
276 // the lsof command name might be truncated, so we prefer /proc/<pid>/exe
277 if (!_fromLsofFileMode)
278 pinfo.command = filesystem::readlink( Pathname("/proc")/pinfo.pid/"exe" ).basename();
279 if ( pinfo.command.empty() )
280 pinfo.command = std::move(commandname);
281 if ( debMap )
282 pLineStr <<'c'<<pinfo.command<<'\0';
283 }
284 break;
285 }
286 if ( *ch == '\n' ) break; // end of data
287 do { ++ch; } while ( *ch != '\0' ); // skip to next field
288 }
289
290 //replace the data in the debug cache as well
291 if ( debMap ) {
292 pLineStr<<endl;
293 debMap->front() = pLineStr.str();
294 }
295
296 //entry was added
297 return true;
298 }
299
300
306 inline void CheckAccessDeleted::Impl::addCacheIf( CacheEntry & cache_r, const std::string & line_r, std::vector<std::string> *debMap )
307 {
308 const char * f = 0;
309 const char * t = 0;
310 const char * n = 0;
311
312 for_( ch, line_r.c_str(), ch+line_r.size() )
313 {
314 switch ( *ch )
315 {
316 case 'k':
317 if ( *(ch+1) != '0' ) // skip non-zero link counts
318 return;
319 break;
320 case 'f':
321 f = ch+1;
322 break;
323 case 't':
324 t = ch+1;
325 break;
326 case 'n':
327 n = ch+1;
328 break;
329 }
330 if ( *ch == '\n' ) break; // end of data
331 do { ++ch; } while ( *ch != '\0' ); // skip to next field
332 }
333
334 if ( !t || !f || !n )
335 return; // wrong filedescriptor/type/name
336
337 if ( !( ( *t == 'R' && *(t+1) == 'E' && *(t+2) == 'G' && *(t+3) == '\0' )
338 || ( *t == 'D' && *(t+1) == 'E' && *(t+2) == 'L' && *(t+3) == '\0' ) ) )
339 return; // wrong type
340
341 if ( !( ( *f == 'm' && *(f+1) == 'e' && *(f+2) == 'm' && *(f+3) == '\0' )
342 || ( *f == 't' && *(f+1) == 'x' && *(f+2) == 't' && *(f+3) == '\0' )
343 || ( *f == 'D' && *(f+1) == 'E' && *(f+2) == 'L' && *(f+3) == '\0' )
344 || ( *f == 'l' && *(f+1) == 't' && *(f+2) == 'x' && *(f+3) == '\0' ) ) )
345 return; // wrong filedescriptor type
346
347 if ( str::contains( n, "(stat: Permission denied)" ) )
348 return; // Avoid reporting false positive due to insufficient permission.
349
350 if ( ! _verbose )
351 {
352 if ( ! ( str::contains( n, "/lib" ) || str::contains( n, "bin/" ) ) )
353 return; // Try to avoid reporting false positive unless verbose.
354 }
355
356 if ( *f == 'm' || *f == 'D' ) // skip some wellknown nonlibrary memorymapped files
357 {
358 static const char * black[] = {
359 "/SYSV"
360 , "/var/"
361 , "/dev/"
362 , "/tmp/"
363 , "/proc/"
364 , "/memfd:"
365 };
367 {
368 if ( str::hasPrefix( n, *it ) )
369 return;
370 }
371 }
372 // Add if no duplicate
373 if ( debMap && cache_r.second.find(n) == cache_r.second.end() ) {
374 debMap->push_back(line_r);
375 }
376 cache_r.second.insert( n );
377 }
378
384
386 {
387 _pimpl->_verbose = verbose_r;
388 _pimpl->_fromLsofFileMode = true;
389
390 FILE *inFile = fopen( lsofOutput_r.c_str(), "r" );
391 if ( !inFile ) {
392 ZYPP_THROW( Exception( str::Format("Opening input file %1% failed.") % lsofOutput_r.c_str() ) );
393 }
394
395 //inFile is closed by ExternalDataSource
397 auto cache = _pimpl->filterInput( inSource );
398 return _pimpl->createProcInfo( cache );
399 }
400
402 {
403 // cachemap: PID => (deleted files)
404 // NOTE: omit PIDs running in a (lxc/docker) container
405 std::map<pid_t,CacheEntry> cachemap;
406
407 bool debugEnabled = !_debugFile.empty();
408
409 pid_t cachepid = 0;
410 FilterRunsInContainer runsInLXC;
411 MIL << "Silently scanning lsof output..." << endl;
412 zypp::base::LogControl::TmpLineWriter shutUp; // suppress excessive readdir etc. logging in runsInLXC
413 for( std::string line = source.receiveLine( 30 * 1000 ); ! line.empty(); line = source.receiveLine( 30 * 1000 ) )
414 {
415 // NOTE: line contains '\0' separeated fields!
416 if ( line[0] == 'p' )
417 {
418 str::strtonum( line.c_str()+1, cachepid ); // line is "p<PID>\0...."
419 if ( _fromLsofFileMode || !runsInLXC( cachepid ) ) {
420 if ( debugEnabled ) {
421 auto &pidMad = debugMap[cachepid];
422 if ( pidMad.empty() )
423 debugMap[cachepid].push_back( line );
424 else
425 debugMap[cachepid].front() = line;
426 }
427 cachemap[cachepid].first.swap( line );
428 } else {
429 cachepid = 0; // ignore this pid
430 }
431 }
432 else if ( cachepid )
433 {
434 auto &dbgMap = debugMap[cachepid];
436 }
437 }
438 return cachemap;
439 }
440
442 {
443 static const char* argv[] = { "lsof", "-n", "-FpcuLRftkn0", "-K", "i", NULL };
444 if ( lsofNoOptKi() )
445 argv[3] = NULL;
446
447 _pimpl->_verbose = verbose_r;
448 _pimpl->_fromLsofFileMode = false;
449
451 std::map<pid_t,CacheEntry> cachemap;
452
453 try {
454 cachemap = _pimpl->filterInput( prog );
455 } catch ( const io::TimeoutException &e ) {
456 ZYPP_CAUGHT( e );
457 prog.kill();
458 ZYPP_THROW ( Exception( "Reading data from 'lsof' timed out.") );
459 }
460
461 int ret = prog.close();
462 if ( ret != 0 )
463 {
464 if ( ret == 129 )
465 {
466 ZYPP_THROW( Exception(_("Please install package 'lsof' first.") ) );
467 }
468 Exception err( str::Format("Executing 'lsof' failed (%1%).") % ret );
469 err.remember( prog.execError() );
470 ZYPP_THROW( err );
471 }
472
473 return _pimpl->createProcInfo( cachemap );
474 }
475
477 {
478 std::ofstream debugFileOut;
479 bool debugEnabled = false;
480 if ( !_debugFile.empty() ) {
481 debugFileOut.open( _debugFile.c_str() );
482 debugEnabled = debugFileOut.is_open();
483
484 if ( !debugEnabled ) {
485 ERR<<"Unable to open debug file: "<<_debugFile<<endl;
486 }
487 }
488
489 _data.clear();
490 for ( const auto &cached : in )
491 {
492 if (!debugEnabled)
493 addDataIf( cached.second);
494 else {
495 std::vector<std::string> *mapPtr = nullptr;
496
497 auto dbgInfo = debugMap.find(cached.first);
498 if ( dbgInfo != debugMap.end() )
499 mapPtr = &(dbgInfo->second);
500
501 if( !addDataIf( cached.second, mapPtr ) )
502 continue;
503
504 for ( const std::string &dbgLine: dbgInfo->second ) {
505 debugFileOut.write( dbgLine.c_str(), dbgLine.length() );
506 }
507 }
508 }
509 return _data.size();
510 }
511
513 {
514 return _pimpl->_data.empty();
515 }
516
518 {
519 return _pimpl->_data.size();
520 }
521
523 {
524 return _pimpl->_data.begin();
525 }
526
528 {
529 return _pimpl->_data.end();
530 }
531
536
538 {
539 ProcInfo p;
540 p.pid = str::numstring( pid_r );
541 return p.service();
542 }
543
545 {
546 // cgroup entries like:
547 // 1:name=systemd:/system.slice/systemd-udevd.service
548 // 0::/system.slice/systemd-udevd.service
549 // 0::/system.slice/systemd-udevd.service/udev
550 static const str::regex rx( "(0::|[0-9]+:name=systemd:)/system.slice/(.*/)?(.*).service(/.*)?$" );
551 str::smatch what;
552 std::string ret;
553 iostr::simpleParseFile( InputStream( Pathname("/proc")/pid/"cgroup" ),
554 [&]( int num_r, const std::string& line_r )->bool
555 {
556 if ( str::regex_match( line_r, what, rx ) )
557 {
558 ret = what[3];
559 return false; // stop after match
560 }
561 return true;
562 } );
563 return ret;
564 }
565
566 /******************************************************************
567 **
568 ** FUNCTION NAME : operator<<
569 ** FUNCTION TYPE : std::ostream &
570 */
571 std::ostream & operator<<( std::ostream & str, const CheckAccessDeleted & obj )
572 {
573 return dumpRange( str << "CheckAccessDeleted ",
574 obj.begin(),
575 obj.end() );
576 }
577
578 /******************************************************************
579 **
580 ** FUNCTION NAME : operator<<
581 ** FUNCTION TYPE : std::ostream &
582 */
583 std::ostream & operator<<( std::ostream & str, const CheckAccessDeleted::ProcInfo & obj )
584 {
585 if ( obj.pid.empty() )
586 return str << "<NoProc>";
587
588 return dumpRangeLine( str << obj.command
589 << '<' << obj.pid
590 << '|' << obj.ppid
591 << '|' << obj.puid
592 << '|' << obj.login
593 << '>',
594 obj.files.begin(),
595 obj.files.end() );
596 }
597
599} // namespace zypp
Reference counted access to a Tp object calling a custom Dispose function when the last AutoDispose h...
Definition AutoDispose.h:95
void swap(AutoDispose &rhs) noexcept
Exchange the contents of two AutoDispose objects.
AutoDispose()
Default Ctor using default constructed value and no dispose function.
CheckAccessDeleted::Impl * clone() const
CheckAccessDeleted::size_type createProcInfo(const std::map< pid_t, CacheEntry > &in)
std::map< pid_t, std::vector< std::string > > debugMap
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::map< pid_t, CacheEntry > filterInput(externalprogram::ExternalDataSource &source)
bool addDataIf(const CacheEntry &cache_r, std::vector< std::string > *debMap=nullptr)
Add cache to data if the process is accessing deleted files.
std::vector< CheckAccessDeleted::ProcInfo > _data
Check for running processes which access deleted executables or libraries.
size_type check(bool verbose_r=false)
Check for running processes which access deleted executables or libraries.
CheckAccessDeleted(bool doCheck_r=true)
Default ctor performs check immediately.
const_iterator end() const
std::ostream & operator<<(std::ostream &str, const CheckAccessDeleted &obj)
Stream output.
const_iterator begin() const
static std::string findService(pid_t pid_r)
Guess if pid was started by a systemd service script.
std::vector< ProcInfo >::const_iterator const_iterator
void setDebugOutputFile(const Pathname &filename_r)
Writes all filtered process entries that make it into the final set into a file specified by filename...
RWCOW_pointer< Impl > _pimpl
Base class for Exception.
Definition Exception.h:147
void remember(const Exception &old_r)
Store an other Exception as history.
Definition Exception.cc:141
Execute a program and give access to its io An object of this class encapsulates the execution of an ...
Helper to create and pass std::istream.
Definition inputstream.h:57
Bidirectional stream to external data.
std::string receiveLine()
Read one line from the input stream.
bool empty() const
Test for an empty path.
Definition Pathname.h:116
Regular expression.
Definition Regex.h:95
Regular expression match result.
Definition Regex.h:168
String related utilities and Regular expression matching.
int dirForEach(const Pathname &dir_r, const StrMatcher &matcher_r, function< bool(const Pathname &, const char *const)> fnc_r)
Definition PathInfo.cc:32
int readlink(const Pathname &symlink_r, Pathname &target_r)
Like 'readlink'.
Definition PathInfo.cc:929
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
std::string numstring(char n, int w=0)
Definition String.h:289
bool hasPrefix(const C_Str &str_r, const C_Str &prefix_r)
Return whether str_r has prefix prefix_r.
Definition String.h:1026
bool regex_match(const std::string &s, smatch &matches, const regex &regex)
\relates regex \ingroup ZYPP_STR_REGEX \relates regex \ingroup ZYPP_STR_REGEX
Definition Regex.h:70
TInt strtonum(const C_Str &str)
Parsing numbers from string.
bool contains(const C_Str &str_r, const C_Str &val_r)
Locate substring case sensitive.
Definition String.h:990
Easy-to use interface to the ZYPP dependency resolver.
std::ostream & dumpRangeLine(std::ostream &str, TIterator begin, TIterator end)
Print range defined by iterators (single line style).
Definition LogTools.h:143
std::ostream & dumpRange(std::ostream &str, TIterator begin, TIterator end, const std::string &intro="{", const std::string &pfx="\n ", const std::string &sep="\n ", const std::string &sfx="\n", const std::string &extro="}")
Print range defined by iterators (multiline style).
Definition LogTools.h:120
std::string asString(const Patch::Category &obj)
Definition Patch.cc:122
Data about one running process accessing deleted files.
std::string service() const
Guess if command was started by a systemd service script.
Exchange LineWriter for the lifetime of this object.
Definition LogControl.h:191
Convenient building of std::string with boost::format.
Definition String.h:253
#define arrayBegin(A)
Simple C-array iterator.
Definition Easy.h:41
#define for_(IT, BEG, END)
Convenient for-loops using iterator.
Definition Easy.h:28
#define arrayEnd(A)
Definition Easy.h:43
#define ZYPP_CAUGHT(EXCPT)
Drops a logline telling the Exception was caught (in order to handle it).
Definition Exception.h:440
#define ZYPP_THROW(EXCPT)
Drops a logline and throws the Exception.
Definition Exception.h:424
#define _(MSG)
Definition Gettext.h:39
#define MIL
Definition Logger.h:98
#define ERR
Definition Logger.h:100
Interface to gettext.