libzypp 17.35.9
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 // bsc#1226014. Ignore snaps. Execuables below /snap/
97 // (may also be detectable via /proc/PID/cgroup)
98 if ( str::startsWith( linkTarget.asString(), "/snap/" ) )
99 return CONTAINER;
100
101 // get stat info for the target file
102 const PathInfo linkStat( linkTarget );
103
104 // Non-existent path means it's not reachable by us.
105 if ( !linkStat.isExist() )
106 return CONTAINER;
107
108 // If the file exists, it could simply mean it exists in and outside a container, check inode to be safe
109 if ( linkStat.ino() != procInfoStat.ino())
110 return CONTAINER;
111
112 // 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
113 if ( linkStat.dev() != procInfoStat.dev() )
114 return CONTAINER;
115
116 // assume HOST if all tests fail
117 return HOST;
118 }
119
120 public:
121
125 bool operator()( const pid_t pid ) const {
126
127 // first check the exe file
128 const Pathname pidDir = Pathname("/proc") / asString(pid);
129 const Pathname exeFile = pidDir / "exe";
130
131 auto res = in_our_root( exeFile );
132 if ( res > IGNORE )
133 return res == CONTAINER;
134
135 // if IGNORE was returned we need to continue testing all the files in /proc/<pid>/map_files until we hopefully
136 // find a still existing file. If all tests fail we will simply assume this pid is running on the HOST
137
138 // 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
139 std::unordered_set<std::string> tested;
140
141 // iterate over all the entries in /proc/<pid>/map_files
142 filesystem::dirForEach( pidDir / "map_files", [ this, &tested, &res ]( const Pathname & dir_r, const char *const & name_r ){
143
144 // some helpers to make the code more self explanatory
145 constexpr bool contloop = true;
146 constexpr bool stoploop = false;
147
148 const Pathname entryName = dir_r / name_r;
149
150 // get the links target file and check if we alreadys know it, also if we can not read link information we skip the file
151 const Pathname linkTarget = filesystem::readlink( entryName );
152 if ( linkTarget.empty() || !tested.insert( linkTarget.asString() ).second ) return contloop;
153
154 // try to get file type
155 const auto mappedFileType = in_our_root( entryName );
156
157 // if we got something, remember the value and stop the loop
158 if ( mappedFileType > IGNORE ) {
159 res = mappedFileType;
160 return stoploop;
161 }
162 return contloop;
163 });
164
165 // If res is still IGNORE, we did not find a explicit answer. So, to be safe, we assume it is running on the host.
166 if ( res == IGNORE )
167 return false; // can't tell for sure, lets assume host
168
169 return res == CONTAINER;
170 }
171
172 FilterRunsInContainer() {}
173 };
174
175
181 bool lsofNoOptKi()
182 {
183 using target::rpm::librpmDb;
184 // RpmDb access is blocked while the Target is not initialized.
185 // Launching the Target just for this query would be an overkill.
186 struct TmpUnblock {
187 TmpUnblock()
188 : _wasBlocked( librpmDb::isBlocked() )
189 { if ( _wasBlocked ) librpmDb::unblockAccess(); }
190 TmpUnblock(const TmpUnblock &) = delete;
191 TmpUnblock(TmpUnblock &&) = delete;
192 TmpUnblock &operator=(const TmpUnblock &) = delete;
193 TmpUnblock &operator=(TmpUnblock &&) = delete;
194 ~TmpUnblock() {
195 if (_wasBlocked)
196 librpmDb::blockAccess();
197 }
198
199 private:
200 bool _wasBlocked;
201 } tmpUnblock;
202
203 librpmDb::db_const_iterator it;
204 return( it.findPackage( "lsof" ) && it->tag_edition() < Edition("4.90") && !it->tag_provides().count( Capability("backported-option-Ki") ) );
205 }
206
207 } //namespace
209
211 {
212 public:
214
215 bool addDataIf( const CacheEntry & cache_r, std::vector<std::string> *debMap = nullptr );
216 void addCacheIf( CacheEntry & cache_r, const std::string & line_r, std::vector<std::string> *debMap = nullptr );
217
218 std::map<pid_t,CacheEntry> filterInput( externalprogram::ExternalDataSource &source );
219 CheckAccessDeleted::size_type createProcInfo( const std::map<pid_t,CacheEntry> &in );
220
221 std::vector<CheckAccessDeleted::ProcInfo> _data;
222 bool _fromLsofFileMode = false; // Set if we currently process data from a debug file
223 bool _verbose = false;
224
225 std::map<pid_t,std::vector<std::string>> debugMap; //will contain all used lsof files after filtering
227 };
228
230 {
231 Impl *myClone = new Impl( *this );
232 return myClone;
233 }
234
239 inline bool CheckAccessDeleted::Impl::addDataIf( const CacheEntry & cache_r, std::vector<std::string> *debMap )
240 {
241 const auto & filelist( cache_r.second );
242
243 if ( filelist.empty() )
244 return false;
245
246 // at least one file access so keep it:
247 _data.push_back( CheckAccessDeleted::ProcInfo() );
248 CheckAccessDeleted::ProcInfo & pinfo( _data.back() );
249 pinfo.files.insert( pinfo.files.begin(), filelist.begin(), filelist.end() );
250
251 const std::string & pline( cache_r.first );
252 std::string commandname; // pinfo.command if still needed...
253 std::ostringstream pLineStr; //rewrite the first line in debug cache
254 for_( ch, pline.begin(), pline.end() )
255 {
256 switch ( *ch )
257 {
258 case 'p':
259 pinfo.pid = &*(ch+1);
260 if ( debMap )
261 pLineStr <<&*(ch)<<'\0';
262 break;
263 case 'R':
264 pinfo.ppid = &*(ch+1);
265 if ( debMap )
266 pLineStr <<&*(ch)<<'\0';
267 break;
268 case 'u':
269 pinfo.puid = &*(ch+1);
270 if ( debMap )
271 pLineStr <<&*(ch)<<'\0';
272 break;
273 case 'L':
274 pinfo.login = &*(ch+1);
275 if ( debMap )
276 pLineStr <<&*(ch)<<'\0';
277 break;
278 case 'c':
279 if ( pinfo.command.empty() ) {
280 commandname = &*(ch+1);
281 // the lsof command name might be truncated, so we prefer /proc/<pid>/exe
282 if (!_fromLsofFileMode)
283 pinfo.command = filesystem::readlink( Pathname("/proc")/pinfo.pid/"exe" ).basename();
284 if ( pinfo.command.empty() )
285 pinfo.command = std::move(commandname);
286 if ( debMap )
287 pLineStr <<'c'<<pinfo.command<<'\0';
288 }
289 break;
290 }
291 if ( *ch == '\n' ) break; // end of data
292 do { ++ch; } while ( *ch != '\0' ); // skip to next field
293 }
294
295 //replace the data in the debug cache as well
296 if ( debMap ) {
297 pLineStr<<endl;
298 debMap->front() = pLineStr.str();
299 }
300
301 //entry was added
302 return true;
303 }
304
305
311 inline void CheckAccessDeleted::Impl::addCacheIf( CacheEntry & cache_r, const std::string & line_r, std::vector<std::string> *debMap )
312 {
313 const char * f = 0;
314 const char * t = 0;
315 const char * n = 0;
316
317 for_( ch, line_r.c_str(), ch+line_r.size() )
318 {
319 switch ( *ch )
320 {
321 case 'k':
322 if ( *(ch+1) != '0' ) // skip non-zero link counts
323 return;
324 break;
325 case 'f':
326 f = ch+1;
327 break;
328 case 't':
329 t = ch+1;
330 break;
331 case 'n':
332 n = ch+1;
333 break;
334 }
335 if ( *ch == '\n' ) break; // end of data
336 do { ++ch; } while ( *ch != '\0' ); // skip to next field
337 }
338
339 if ( !t || !f || !n )
340 return; // wrong filedescriptor/type/name
341
342 if ( !( ( *t == 'R' && *(t+1) == 'E' && *(t+2) == 'G' && *(t+3) == '\0' )
343 || ( *t == 'D' && *(t+1) == 'E' && *(t+2) == 'L' && *(t+3) == '\0' ) ) )
344 return; // wrong type
345
346 if ( !( ( *f == 'm' && *(f+1) == 'e' && *(f+2) == 'm' && *(f+3) == '\0' )
347 || ( *f == 't' && *(f+1) == 'x' && *(f+2) == 't' && *(f+3) == '\0' )
348 || ( *f == 'D' && *(f+1) == 'E' && *(f+2) == 'L' && *(f+3) == '\0' )
349 || ( *f == 'l' && *(f+1) == 't' && *(f+2) == 'x' && *(f+3) == '\0' ) ) )
350 return; // wrong filedescriptor type
351
352 if ( str::contains( n, "(stat: Permission denied)" ) )
353 return; // Avoid reporting false positive due to insufficient permission.
354
355 if ( ! _verbose )
356 {
357 if ( ! ( str::contains( n, "/lib" ) || str::contains( n, "bin/" ) ) )
358 return; // Try to avoid reporting false positive unless verbose.
359 }
360
361 if ( *f == 'm' || *f == 'D' ) // skip some wellknown nonlibrary memorymapped files
362 {
363 static const char * black[] = {
364 "/SYSV"
365 , "/var/"
366 , "/dev/"
367 , "/tmp/"
368 , "/proc/"
369 , "/memfd:"
370 , "/snap/"
371 };
373 {
374 if ( str::hasPrefix( n, *it ) )
375 return;
376 }
377 }
378 // Add if no duplicate
379 if ( debMap && cache_r.second.find(n) == cache_r.second.end() ) {
380 debMap->push_back(line_r);
381 }
382 cache_r.second.insert( n );
383 }
384
390
392 {
393 _pimpl->_verbose = verbose_r;
394 _pimpl->_fromLsofFileMode = true;
395
396 FILE *inFile = fopen( lsofOutput_r.c_str(), "r" );
397 if ( !inFile ) {
398 ZYPP_THROW( Exception( str::Format("Opening input file %1% failed.") % lsofOutput_r.c_str() ) );
399 }
400
401 //inFile is closed by ExternalDataSource
403 auto cache = _pimpl->filterInput( inSource );
404 return _pimpl->createProcInfo( cache );
405 }
406
408 {
409 // cachemap: PID => (deleted files)
410 // NOTE: omit PIDs running in a (lxc/docker) container
411 std::map<pid_t,CacheEntry> cachemap;
412
413 bool debugEnabled = !_debugFile.empty();
414
415 pid_t cachepid = 0;
416 FilterRunsInContainer runsInLXC;
417 MIL << "Silently scanning lsof output..." << endl;
418 zypp::base::LogControl::TmpLineWriter shutUp; // suppress excessive readdir etc. logging in runsInLXC
419 for( std::string line = source.receiveLine( 30 * 1000 ); ! line.empty(); line = source.receiveLine( 30 * 1000 ) )
420 {
421 // NOTE: line contains '\0' separeated fields!
422 if ( line[0] == 'p' )
423 {
424 str::strtonum( line.c_str()+1, cachepid ); // line is "p<PID>\0...."
425 if ( _fromLsofFileMode || !runsInLXC( cachepid ) ) {
426 if ( debugEnabled ) {
427 auto &pidMad = debugMap[cachepid];
428 if ( pidMad.empty() )
429 debugMap[cachepid].push_back( line );
430 else
431 debugMap[cachepid].front() = line;
432 }
433 cachemap[cachepid].first.swap( line );
434 } else {
435 cachepid = 0; // ignore this pid
436 }
437 }
438 else if ( cachepid )
439 {
440 auto &dbgMap = debugMap[cachepid];
442 }
443 }
444 return cachemap;
445 }
446
448 {
449 static const char* argv[] = { "lsof", "-n", "-FpcuLRftkn0", "-K", "i", NULL };
450 if ( lsofNoOptKi() )
451 argv[3] = NULL;
452
453 _pimpl->_verbose = verbose_r;
454 _pimpl->_fromLsofFileMode = false;
455
457 std::map<pid_t,CacheEntry> cachemap;
458
459 try {
460 cachemap = _pimpl->filterInput( prog );
461 } catch ( const io::TimeoutException &e ) {
462 ZYPP_CAUGHT( e );
463 prog.kill();
464 ZYPP_THROW ( Exception( "Reading data from 'lsof' timed out.") );
465 }
466
467 int ret = prog.close();
468 if ( ret != 0 )
469 {
470 if ( ret == 129 )
471 {
472 ZYPP_THROW( Exception(_("Please install package 'lsof' first.") ) );
473 }
474 Exception err( str::Format("Executing 'lsof' failed (%1%).") % ret );
475 err.remember( prog.execError() );
476 ZYPP_THROW( err );
477 }
478
479 return _pimpl->createProcInfo( cachemap );
480 }
481
483 {
484 std::ofstream debugFileOut;
485 bool debugEnabled = false;
486 if ( !_debugFile.empty() ) {
487 debugFileOut.open( _debugFile.c_str() );
488 debugEnabled = debugFileOut.is_open();
489
490 if ( !debugEnabled ) {
491 ERR<<"Unable to open debug file: "<<_debugFile<<endl;
492 }
493 }
494
495 _data.clear();
496 for ( const auto &cached : in )
497 {
498 if (!debugEnabled)
499 addDataIf( cached.second);
500 else {
501 std::vector<std::string> *mapPtr = nullptr;
502
503 auto dbgInfo = debugMap.find(cached.first);
504 if ( dbgInfo != debugMap.end() )
505 mapPtr = &(dbgInfo->second);
506
507 if( !addDataIf( cached.second, mapPtr ) )
508 continue;
509
510 for ( const std::string &dbgLine: dbgInfo->second ) {
511 debugFileOut.write( dbgLine.c_str(), dbgLine.length() );
512 }
513 }
514 }
515 return _data.size();
516 }
517
519 {
520 return _pimpl->_data.empty();
521 }
522
524 {
525 return _pimpl->_data.size();
526 }
527
529 {
530 return _pimpl->_data.begin();
531 }
532
534 {
535 return _pimpl->_data.end();
536 }
537
542
544 {
545 ProcInfo p;
546 p.pid = str::numstring( pid_r );
547 return p.service();
548 }
549
551 {
552 // cgroup entries like:
553 // 1:name=systemd:/system.slice/systemd-udevd.service
554 // 0::/system.slice/systemd-udevd.service
555 // 0::/system.slice/systemd-udevd.service/udev
556 static const str::regex rx( "(0::|[0-9]+:name=systemd:)/system.slice/(.*/)?(.*).service(/.*)?$" );
557 str::smatch what;
558 std::string ret;
559 iostr::simpleParseFile( InputStream( Pathname("/proc")/pid/"cgroup" ),
560 [&]( int num_r, const std::string& line_r )->bool
561 {
562 if ( str::regex_match( line_r, what, rx ) )
563 {
564 ret = what[3];
565 return false; // stop after match
566 }
567 return true;
568 } );
569 return ret;
570 }
571
572 /******************************************************************
573 **
574 ** FUNCTION NAME : operator<<
575 ** FUNCTION TYPE : std::ostream &
576 */
577 std::ostream & operator<<( std::ostream & str, const CheckAccessDeleted & obj )
578 {
579 return dumpRange( str << "CheckAccessDeleted ",
580 obj.begin(),
581 obj.end() );
582 }
583
584 /******************************************************************
585 **
586 ** FUNCTION NAME : operator<<
587 ** FUNCTION TYPE : std::ostream &
588 */
589 std::ostream & operator<<( std::ostream & str, const CheckAccessDeleted::ProcInfo & obj )
590 {
591 if ( obj.pid.empty() )
592 return str << "<NoProc>";
593
594 return dumpRangeLine( str << obj.command
595 << '<' << obj.pid
596 << '|' << obj.ppid
597 << '|' << obj.puid
598 << '|' << obj.login
599 << '>',
600 obj.files.begin(),
601 obj.files.end() );
602 }
603
605} // 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 startsWith(const C_Str &str_r, const C_Str &prefix_r)
alias for hasPrefix
Definition String.h:1084
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.