libzypp 17.35.19
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;
185 return( it.findPackage( "lsof" ) && it->tag_edition() < Edition("4.90") && !it->tag_provides().count( Capability("backported-option-Ki") ) );
186 }
187
188 } //namespace
190
192 {
193 public:
195
196 bool addDataIf( const CacheEntry & cache_r, std::vector<std::string> *debMap = nullptr );
197 void addCacheIf( CacheEntry & cache_r, const std::string & line_r, std::vector<std::string> *debMap = nullptr );
198
199 std::map<pid_t,CacheEntry> filterInput( externalprogram::ExternalDataSource &source );
200 CheckAccessDeleted::size_type createProcInfo( const std::map<pid_t,CacheEntry> &in );
201
202 std::vector<CheckAccessDeleted::ProcInfo> _data;
203 bool _fromLsofFileMode = false; // Set if we currently process data from a debug file
204 bool _verbose = false;
205
206 std::map<pid_t,std::vector<std::string>> debugMap; //will contain all used lsof files after filtering
208 };
209
211 {
212 Impl *myClone = new Impl( *this );
213 return myClone;
214 }
215
220 inline bool CheckAccessDeleted::Impl::addDataIf( const CacheEntry & cache_r, std::vector<std::string> *debMap )
221 {
222 const auto & filelist( cache_r.second );
223
224 if ( filelist.empty() )
225 return false;
226
227 // at least one file access so keep it:
228 _data.push_back( CheckAccessDeleted::ProcInfo() );
229 CheckAccessDeleted::ProcInfo & pinfo( _data.back() );
230 pinfo.files.insert( pinfo.files.begin(), filelist.begin(), filelist.end() );
231
232 const std::string & pline( cache_r.first );
233 std::string commandname; // pinfo.command if still needed...
234 std::ostringstream pLineStr; //rewrite the first line in debug cache
235 for_( ch, pline.begin(), pline.end() )
236 {
237 switch ( *ch )
238 {
239 case 'p':
240 pinfo.pid = &*(ch+1);
241 if ( debMap )
242 pLineStr <<&*(ch)<<'\0';
243 break;
244 case 'R':
245 pinfo.ppid = &*(ch+1);
246 if ( debMap )
247 pLineStr <<&*(ch)<<'\0';
248 break;
249 case 'u':
250 pinfo.puid = &*(ch+1);
251 if ( debMap )
252 pLineStr <<&*(ch)<<'\0';
253 break;
254 case 'L':
255 pinfo.login = &*(ch+1);
256 if ( debMap )
257 pLineStr <<&*(ch)<<'\0';
258 break;
259 case 'c':
260 if ( pinfo.command.empty() ) {
261 commandname = &*(ch+1);
262 // the lsof command name might be truncated, so we prefer /proc/<pid>/exe
263 if (!_fromLsofFileMode)
264 pinfo.command = filesystem::readlink( Pathname("/proc")/pinfo.pid/"exe" ).basename();
265 if ( pinfo.command.empty() )
266 pinfo.command = std::move(commandname);
267 if ( debMap )
268 pLineStr <<'c'<<pinfo.command<<'\0';
269 }
270 break;
271 }
272 if ( *ch == '\n' ) break; // end of data
273 do { ++ch; } while ( *ch != '\0' ); // skip to next field
274 }
275
276 //replace the data in the debug cache as well
277 if ( debMap ) {
278 pLineStr<<endl;
279 debMap->front() = pLineStr.str();
280 }
281
282 //entry was added
283 return true;
284 }
285
286
292 inline void CheckAccessDeleted::Impl::addCacheIf( CacheEntry & cache_r, const std::string & line_r, std::vector<std::string> *debMap )
293 {
294 const char * f = 0;
295 const char * t = 0;
296 const char * n = 0;
297
298 // match any stat error appended to file path
299 static const str::regex statErr(R"(.*\‍(stat: [^)]+\)$)");
300
301 for_( ch, line_r.c_str(), ch+line_r.size() )
302 {
303 switch ( *ch )
304 {
305 case 'k':
306 if ( *(ch+1) != '0' ) // skip non-zero link counts
307 return;
308 break;
309 case 'f':
310 f = ch+1;
311 break;
312 case 't':
313 t = ch+1;
314 break;
315 case 'n':
316 n = ch+1;
317 break;
318 }
319 if ( *ch == '\n' ) break; // end of data
320 do { ++ch; } while ( *ch != '\0' ); // skip to next field
321 }
322
323 if ( !t || !f || !n )
324 return; // wrong filedescriptor/type/name
325
326 if ( !( ( *t == 'R' && *(t+1) == 'E' && *(t+2) == 'G' && *(t+3) == '\0' )
327 || ( *t == 'D' && *(t+1) == 'E' && *(t+2) == 'L' && *(t+3) == '\0' ) ) )
328 return; // wrong type
329
330 if ( !( ( *f == 'm' && *(f+1) == 'e' && *(f+2) == 'm' && *(f+3) == '\0' )
331 || ( *f == 't' && *(f+1) == 'x' && *(f+2) == 't' && *(f+3) == '\0' )
332 || ( *f == 'D' && *(f+1) == 'E' && *(f+2) == 'L' && *(f+3) == '\0' )
333 || ( *f == 'l' && *(f+1) == 't' && *(f+2) == 'x' && *(f+3) == '\0' ) ) )
334 return; // wrong filedescriptor type
335
336 // lib/dialects/linux/dproc.c will append stat error to file path
337 // if the file has not been detected as deleted. Ignore those cases
338 if ( str::regex_match( n, statErr ) )
339 return; // Avoid reporting false positive due to insufficient permission.
340
341 if ( ! _verbose )
342 {
343 if ( ! ( str::contains( n, "/lib" ) || str::contains( n, "bin/" ) ) )
344 return; // Try to avoid reporting false positive unless verbose.
345 }
346
347 if ( *f == 'm' || *f == 'D' ) // skip some wellknown nonlibrary memorymapped files
348 {
349 static const char * black[] = {
350 "/SYSV"
351 , "/var/"
352 , "/dev/"
353 , "/tmp/"
354 , "/proc/"
355 , "/memfd:"
356 , "/snap/"
357 };
359 {
360 if ( str::hasPrefix( n, *it ) )
361 return;
362 }
363 }
364 // Add if no duplicate
365 if ( debMap && cache_r.second.find(n) == cache_r.second.end() ) {
366 debMap->push_back(line_r);
367 }
368 cache_r.second.insert( n );
369 }
370
376
378 {
379 _pimpl->_verbose = verbose_r;
380 _pimpl->_fromLsofFileMode = true;
381
382 FILE *inFile = fopen( lsofOutput_r.c_str(), "r" );
383 if ( !inFile ) {
384 ZYPP_THROW( Exception( str::Format("Opening input file %1% failed.") % lsofOutput_r.c_str() ) );
385 }
386
387 //inFile is closed by ExternalDataSource
389 auto cache = _pimpl->filterInput( inSource );
390 return _pimpl->createProcInfo( cache );
391 }
392
394 {
395 // cachemap: PID => (deleted files)
396 // NOTE: omit PIDs running in a (lxc/docker) container
397 std::map<pid_t,CacheEntry> cachemap;
398
399 bool debugEnabled = !_debugFile.empty();
400
401 pid_t cachepid = 0;
402 FilterRunsInContainer runsInLXC;
403 MIL << "Silently scanning lsof output..." << endl;
404 zypp::base::LogControl::TmpLineWriter shutUp; // suppress excessive readdir etc. logging in runsInLXC
405 for( std::string line = source.receiveLine( 30 * 1000 ); ! line.empty(); line = source.receiveLine( 30 * 1000 ) )
406 {
407 // NOTE: line contains '\0' separeated fields!
408 if ( line[0] == 'p' )
409 {
410 str::strtonum( line.c_str()+1, cachepid ); // line is "p<PID>\0...."
411 if ( _fromLsofFileMode || !runsInLXC( cachepid ) ) {
412 if ( debugEnabled ) {
413 auto &pidMad = debugMap[cachepid];
414 if ( pidMad.empty() )
415 debugMap[cachepid].push_back( line );
416 else
417 debugMap[cachepid].front() = line;
418 }
419 cachemap[cachepid].first.swap( line );
420 } else {
421 cachepid = 0; // ignore this pid
422 }
423 }
424 else if ( cachepid )
425 {
426 auto &dbgMap = debugMap[cachepid];
428 }
429 }
430 return cachemap;
431 }
432
434 {
435 static const char* argv[] = { "lsof", "-n", "-FpcuLRftkn0", "-K", "i", NULL };
436 if ( lsofNoOptKi() )
437 argv[3] = NULL;
438
439 _pimpl->_verbose = verbose_r;
440 _pimpl->_fromLsofFileMode = false;
441
443 std::map<pid_t,CacheEntry> cachemap;
444
445 try {
446 cachemap = _pimpl->filterInput( prog );
447 } catch ( const io::TimeoutException &e ) {
448 ZYPP_CAUGHT( e );
449 prog.kill();
450 ZYPP_THROW ( Exception( "Reading data from 'lsof' timed out.") );
451 }
452
453 int ret = prog.close();
454 if ( ret != 0 )
455 {
456 if ( ret == 129 )
457 {
458 ZYPP_THROW( Exception(_("Please install package 'lsof' first.") ) );
459 }
460 Exception err( str::Format("Executing 'lsof' failed (%1%).") % ret );
461 err.remember( prog.execError() );
462 ZYPP_THROW( err );
463 }
464
465 return _pimpl->createProcInfo( cachemap );
466 }
467
469 {
470 std::ofstream debugFileOut;
471 bool debugEnabled = false;
472 if ( !_debugFile.empty() ) {
473 debugFileOut.open( _debugFile.c_str() );
474 debugEnabled = debugFileOut.is_open();
475
476 if ( !debugEnabled ) {
477 ERR<<"Unable to open debug file: "<<_debugFile<<endl;
478 }
479 }
480
481 _data.clear();
482 for ( const auto &cached : in )
483 {
484 if (!debugEnabled)
485 addDataIf( cached.second);
486 else {
487 std::vector<std::string> *mapPtr = nullptr;
488
489 auto dbgInfo = debugMap.find(cached.first);
490 if ( dbgInfo != debugMap.end() )
491 mapPtr = &(dbgInfo->second);
492
493 if( !addDataIf( cached.second, mapPtr ) )
494 continue;
495
496 for ( const std::string &dbgLine: dbgInfo->second ) {
497 debugFileOut.write( dbgLine.c_str(), dbgLine.length() );
498 }
499 }
500 }
501 return _data.size();
502 }
503
505 {
506 return _pimpl->_data.empty();
507 }
508
510 {
511 return _pimpl->_data.size();
512 }
513
515 {
516 return _pimpl->_data.begin();
517 }
518
520 {
521 return _pimpl->_data.end();
522 }
523
528
530 {
531 ProcInfo p;
532 p.pid = str::numstring( pid_r );
533 return p.service();
534 }
535
537 {
538 // cgroup entries like:
539 // 1:name=systemd:/system.slice/systemd-udevd.service
540 // 0::/system.slice/systemd-udevd.service
541 // 0::/system.slice/systemd-udevd.service/udev
542 static const str::regex rx( "(0::|[0-9]+:name=systemd:)/system.slice/(.*/)?(.*).service(/.*)?$" );
543 str::smatch what;
544 std::string ret;
545 iostr::simpleParseFile( InputStream( Pathname("/proc")/pid/"cgroup" ),
546 [&]( int num_r, const std::string& line_r )->bool
547 {
548 if ( str::regex_match( line_r, what, rx ) )
549 {
550 ret = what[3];
551 return false; // stop after match
552 }
553 return true;
554 } );
555 return ret;
556 }
557
558 /******************************************************************
559 **
560 ** FUNCTION NAME : operator<<
561 ** FUNCTION TYPE : std::ostream &
562 */
563 std::ostream & operator<<( std::ostream & str, const CheckAccessDeleted & obj )
564 {
565 return dumpRange( str << "CheckAccessDeleted ",
566 obj.begin(),
567 obj.end() );
568 }
569
570 /******************************************************************
571 **
572 ** FUNCTION NAME : operator<<
573 ** FUNCTION TYPE : std::ostream &
574 */
575 std::ostream & operator<<( std::ostream & str, const CheckAccessDeleted::ProcInfo & obj )
576 {
577 if ( obj.pid.empty() )
578 return str << "<NoProc>";
579
580 return dumpRangeLine( str << obj.command
581 << '<' << obj.pid
582 << '|' << obj.ppid
583 << '|' << obj.puid
584 << '|' << obj.login
585 << '>',
586 obj.files.begin(),
587 obj.files.end() );
588 }
589
591} // namespace zypp
Subclass to retrieve rpm database content.
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.
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:100
#define ERR
Definition Logger.h:102
Interface to gettext.