diff options
Diffstat (limited to 'man2/execve.2')
| -rw-r--r-- | man2/execve.2 | 134 |
1 files changed, 73 insertions, 61 deletions
diff --git a/man2/execve.2 b/man2/execve.2 index 03dfdcdcf..37e62edfa 100644 --- a/man2/execve.2 +++ b/man2/execve.2 @@ -72,7 +72,7 @@ standardised variants of this function provided by libc, including ones that search the .B PATH environment variable, see -.BR exec (3). +.MR exec 3 . .P The argument vector and environment can be accessed by the new program's main function, when it is defined as: @@ -87,7 +87,7 @@ Note, however, that the use of a third argument to the main function is not specified in POSIX.1; according to POSIX.1, the environment should be accessed via the external variable -.BR environ (7). +.MR environ 7 . .P .BR execve () does not return on success, and the text, initialized data, @@ -114,20 +114,20 @@ if any of the following is true: the .I no_new_privs attribute is set for the calling thread (see -.BR prctl (2)); +.MR prctl 2 ); .IP \[bu] the underlying filesystem is mounted .I nosuid (the .B MS_NOSUID flag for -.BR mount (2)); +.MR mount 2 ); or .IP \[bu] the calling process is being ptraced. .P The capabilities of the program file (see -.BR capabilities (7)) +.MR capabilities 7 ) are also ignored if any of the above are true. .P The effective user ID of the process is copied to the saved set-user-ID; @@ -142,7 +142,7 @@ are unchanged by a call to If the executable is an a.out dynamically linked binary executable containing shared-library stubs, the Linux dynamic linker -.BR ld.so (8) +.MR ld.so 8 is called at the start of execution to bring needed shared objects into memory and link the executable with them. @@ -153,7 +153,7 @@ shared objects. This interpreter is typically .I /lib/ld\-linux.so.2 for binaries linked with glibc (see -.BR ld\-linux.so (8)). +.MR ld\-linux.so 8 ). .\" .SS Effect on process attributes All process attributes are preserved during an @@ -162,42 +162,53 @@ except the following: .IP \[bu] 3 The dispositions of any signals that are being caught are reset to the default -.RB ( signal (7)). +\%(\c +.MR signal 7 ). .IP \[bu] Any alternate signal stack is not preserved -.RB ( sigaltstack (2)). +\%(\c +.MR sigaltstack 2 ). .IP \[bu] Memory mappings are not preserved -.RB ( mmap (2)). +\%(\c +.MR mmap 2 ). .IP \[bu] Attached System\ V shared memory segments are detached -.RB ( shmat (2)). +\%(\c +.MR shmat 2 ). .IP \[bu] POSIX shared memory regions are unmapped -.RB ( shm_open (3)). +\%(\c +.MR shm_open 3 ). .IP \[bu] Open POSIX message queue descriptors are closed -.RB ( mq_overview (7)). +\%(\c +.MR mq_overview 7 ). .IP \[bu] Any open POSIX named semaphores are closed -.RB ( sem_overview (7)). +\%(\c +.MR sem_overview 7 ). .IP \[bu] POSIX timers are not preserved -.RB ( timer_create (2)). +\%(\c +.MR timer_create 2 ). .IP \[bu] Any open directory streams are closed -.RB ( opendir (3)). +\%(\c +.MR opendir 3 ). .IP \[bu] Memory locks are not preserved -.RB ( mlock (2), -.BR mlockall (2)). +\%(\c +.MR mlock 2 , +.MR mlockall 2 ). .IP \[bu] Exit handlers are not preserved -.RB ( atexit (3), -.BR on_exit (3)). +\%(\c +.MR atexit 3 , +.MR on_exit 3 ). .IP \[bu] The floating-point environment is reset to the default (see -.BR fenv (3)). +.MR fenv 3 ). .P The process attributes in the preceding list are all specified in POSIX.1. @@ -213,29 +224,29 @@ in which case the dumpable flag may instead be reset to the value in in the circumstances described under .B PR_SET_DUMPABLE in -.BR prctl (2). +.MR prctl 2 . Note that changes to the "dumpable" attribute may cause ownership of files in the process's .IR /proc/ pid directory to change to .IR root:root , as described in -.BR proc (5). +.MR proc 5 . .IP \[bu] The -.BR prctl (2) +.MR prctl 2 .B PR_SET_KEEPCAPS flag is cleared. .IP \[bu] (Since Linux 2.4.36 / 2.6.23) If a set-user-ID or set-group-ID program is being executed, then the parent death signal set by -.BR prctl (2) +.MR prctl 2 .B PR_SET_PDEATHSIG flag is cleared. .IP \[bu] The process name, as set by -.BR prctl (2) +.MR prctl 2 .B PR_SET_NAME (and displayed by .IR "ps\ \-o comm" ), @@ -246,17 +257,17 @@ The .I securebits flag is cleared. See -.BR capabilities (7). +.MR capabilities 7 . .IP \[bu] The termination signal is reset to .B SIGCHLD (see -.BR clone (2)). +.MR clone 2 ). .IP \[bu] The file descriptor table is unshared, undoing the effect of the .B CLONE_FILES flag of -.BR clone (2). +.MR clone 2 . .P Note the following further points: .IP \[bu] 3 @@ -276,13 +287,14 @@ then an implementation may leave the disposition unchanged or reset it to the default; Linux does the former. .IP \[bu] Any outstanding asynchronous I/O operations are canceled -.RB ( aio_read (3), -.BR aio_write (3)). +\%(\c +.MR aio_read 3 , +.MR aio_write 3 ). .IP \[bu] For the handling of capabilities during .BR execve (), see -.BR capabilities (7). +.MR capabilities 7 . .IP \[bu] By default, file descriptors remain open across an .BR execve (). @@ -290,11 +302,11 @@ File descriptors that are marked close-on-exec are closed; see the description of .B FD_CLOEXEC in -.BR fcntl (2). +.MR fcntl 2 . (If a file descriptor is closed, this will cause the release of all record locks obtained on the underlying file by this process. See -.BR fcntl (2) +.MR fcntl 2 for details.) POSIX.1 says that if file descriptors 0, 1, and 2 would otherwise be closed after a successful @@ -395,7 +407,7 @@ On Linux 2.6.23 and later, most architectures support a size limit derived from the soft .B RLIMIT_STACK resource limit (see -.BR getrlimit (2)) +.MR getrlimit 2 ) that is in force at the time of the .BR execve () call. @@ -455,7 +467,7 @@ Search permission is denied on a component of the path prefix of .I pathname or the name of a script interpreter. (See also -.BR path_resolution (7).) +.MR path_resolution 7 .) .TP .B EACCES The file or a script interpreter is not a regular file. @@ -474,7 +486,7 @@ Having changed its real UID using one of the calls, the caller was\[em]and is now still\[em]above its .B RLIMIT_NPROC resource limit (see -.BR setrlimit (2)). +.MR setrlimit 2 ). For a more detailed explanation of this error, see NOTES. .TP .B EFAULT @@ -553,7 +565,7 @@ file has the set-user-ID or set-group-ID bit set. A "capability-dumb" applications would not obtain the full set of permitted capabilities granted by the executable file. See -.BR capabilities (7). +.MR capabilities 7 . .TP .B ETXTBSY The specified executable was open for writing by one or more processes. @@ -584,7 +596,7 @@ case the same as Linux. .\" .P POSIX.1 says that values returned by -.BR sysconf (3) +.MR sysconf 3 should be invariant over the lifetime of a process. However, since Linux 2.6.23, if the .B RLIMIT_STACK @@ -647,7 +659,7 @@ Since UNIX\ V7, both are NULL. One sometimes sees .BR execve () (and the related functions described in -.BR exec (3)) +.MR exec 3 ) described as "executing a .I new process" (or similar). @@ -661,7 +673,7 @@ does is arrange for an existing process (the calling process) to execute a new program. .P Set-user-ID and set-group-ID processes can not be -.BR ptrace (2)d. +.MR ptrace 2 d. .P The result of mounting a filesystem .I nosuid @@ -702,10 +714,10 @@ The error can occur when a .I preceding call to -.BR setuid (2), -.BR setreuid (2), +.MR setuid 2 , +.MR setreuid 2 , or -.BR setresuid (2) +.MR setresuid 2 caused the real user ID of the process to change, and that change caused the process to exceed its .B RLIMIT_NPROC @@ -744,7 +756,7 @@ This kernel logic ensures that the .B RLIMIT_NPROC resource limit is still enforced for the common privileged daemon workflow\[em]namely, -.BR fork (2) +.MR fork 2 + .BR set*uid () + @@ -763,7 +775,7 @@ call succeeds and the kernel clears the .B PF_NPROC_EXCEEDED process flag. The flag is also cleared if a subsequent call to -.BR fork (2) +.MR fork 2 by this process succeeds. .\" .\" .SH BUGS @@ -872,18 +884,18 @@ argv[4]: world .EE .in .SH SEE ALSO -.BR chmod (2), -.BR execveat (2), -.BR fork (2), -.BR get_robust_list (2), -.BR ptrace (2), -.BR exec (3), -.BR fexecve (3), -.BR getauxval (3), -.BR getopt (3), -.BR system (3), -.BR capabilities (7), -.BR credentials (7), -.BR environ (7), -.BR path_resolution (7), -.BR ld.so (8) +.MR chmod 2 , +.MR execveat 2 , +.MR fork 2 , +.MR get_robust_list 2 , +.MR ptrace 2 , +.MR exec 3 , +.MR fexecve 3 , +.MR getauxval 3 , +.MR getopt 3 , +.MR system 3 , +.MR capabilities 7 , +.MR credentials 7 , +.MR environ 7 , +.MR path_resolution 7 , +.MR ld.so 8 |