diff options
Diffstat (limited to 'man/man2/prctl.2')
| -rw-r--r-- | man/man2/prctl.2 | 257 |
1 files changed, 3 insertions, 254 deletions
diff --git a/man/man2/prctl.2 b/man/man2/prctl.2 index 9222d2ce92..087a29ca3e 100644 --- a/man/man2/prctl.2 +++ b/man/man2/prctl.2 @@ -18,7 +18,6 @@ .\" 2008-06-13 Erik Bosman, <ejbosman@cs.vu.nl> .\" Document PR_GET_TSC and PR_SET_TSC. .\" 2008-06-15 mtk, Document PR_SET_SECCOMP, PR_GET_SECCOMP -.\" 2012-04 Cyrill Gorcunov, Document PR_SET_MM .\" 2012-04-25 Michael Kerrisk, Document PR_TASK_PERF_EVENTS_DISABLE and .\" PR_TASK_PERF_EVENTS_ENABLE .\" 2012-09-20 Kees Cook, update PR_SET_SECCOMP for mode 2 @@ -99,184 +98,8 @@ The first argument can be: .B PR_MCE_KILL .TQ .B PR_MCE_KILL_GET -.\" prctl PR_SET_MM -.TP -.BR PR_SET_MM " (since Linux 3.3)" -.\" commit 028ee4be34a09a6d48bdf30ab991ae933a7bc036 -Modify certain kernel memory map descriptor fields -of the calling process. -Usually these fields are set by the kernel and dynamic loader (see -.BR ld.so (8) -for more information) and a regular application should not use this feature. -However, there are cases, such as self-modifying programs, -where a program might find it useful to change its own memory map. -.IP -The calling process must have the -.B CAP_SYS_RESOURCE -capability. -The value in -.I arg2 -is one of the options below, while -.I arg3 -provides a new value for the option. -The -.I arg4 -and -.I arg5 -arguments must be zero if unused. -.IP -Before Linux 3.10, -.\" commit 52b3694157e3aa6df871e283115652ec6f2d31e0 -this feature is available only if the kernel is built with the -.B CONFIG_CHECKPOINT_RESTORE -option enabled. -.RS -.TP -.B PR_SET_MM_START_CODE -Set the address above which the program text can run. -The corresponding memory area must be readable and executable, -but not writable or shareable (see -.BR mprotect (2) -and -.BR mmap (2) -for more information). -.TP -.B PR_SET_MM_END_CODE -Set the address below which the program text can run. -The corresponding memory area must be readable and executable, -but not writable or shareable. -.TP -.B PR_SET_MM_START_DATA -Set the address above which initialized and -uninitialized (bss) data are placed. -The corresponding memory area must be readable and writable, -but not executable or shareable. -.TP -.B PR_SET_MM_END_DATA -Set the address below which initialized and -uninitialized (bss) data are placed. -The corresponding memory area must be readable and writable, -but not executable or shareable. -.TP -.B PR_SET_MM_START_STACK -Set the start address of the stack. -The corresponding memory area must be readable and writable. -.TP -.B PR_SET_MM_START_BRK -Set the address above which the program heap can be expanded with -.BR brk (2) -call. -The address must be greater than the ending address of -the current program data segment. -In addition, the combined size of the resulting heap and -the size of the data segment can't exceed the -.B RLIMIT_DATA -resource limit (see -.BR setrlimit (2)). -.TP -.B PR_SET_MM_BRK -Set the current -.BR brk (2) -value. -The requirements for the address are the same as for the -.B PR_SET_MM_START_BRK -option. -.P -The following options are available since Linux 3.5. -.\" commit fe8c7f5cbf91124987106faa3bdf0c8b955c4cf7 -.TP -.B PR_SET_MM_ARG_START -Set the address above which the program command line is placed. -.TP -.B PR_SET_MM_ARG_END -Set the address below which the program command line is placed. -.TP -.B PR_SET_MM_ENV_START -Set the address above which the program environment is placed. -.TP -.B PR_SET_MM_ENV_END -Set the address below which the program environment is placed. -.IP -The address passed with -.BR PR_SET_MM_ARG_START , -.BR PR_SET_MM_ARG_END , -.BR PR_SET_MM_ENV_START , -and -.B PR_SET_MM_ENV_END -should belong to a process stack area. -Thus, the corresponding memory area must be readable, writable, and -(depending on the kernel configuration) have the -.B MAP_GROWSDOWN -attribute set (see -.BR mmap (2)). -.TP -.B PR_SET_MM_AUXV -Set a new auxiliary vector. -The -.I arg3 -argument should provide the address of the vector. -The -.I arg4 -is the size of the vector. -.TP -.B PR_SET_MM_EXE_FILE -.\" commit b32dfe377102ce668775f8b6b1461f7ad428f8b6 -Supersede the -.IR /proc/ pid /exe -symbolic link with a new one pointing to a new executable file -identified by the file descriptor provided in -.I arg3 -argument. -The file descriptor should be obtained with a regular -.BR open (2) -call. -.IP -To change the symbolic link, one needs to unmap all existing -executable memory areas, including those created by the kernel itself -(for example the kernel usually creates at least one executable -memory area for the ELF -.I .text -section). -.IP -In Linux 4.9 and earlier, the -.\" commit 3fb4afd9a504c2386b8435028d43283216bf588e -.B PR_SET_MM_EXE_FILE -operation can be performed only once in a process's lifetime; -attempting to perform the operation a second time results in the error -.BR EPERM . -This restriction was enforced for security reasons that were subsequently -deemed specious, -and the restriction was removed in Linux 4.10 because some -user-space applications needed to perform this operation more than once. -.P -The following options are available since Linux 3.18. -.\" commit f606b77f1a9e362451aca8f81d8f36a3a112139e -.TP -.B PR_SET_MM_MAP -Provides one-shot access to all the addresses by passing in a -.I struct prctl_mm_map -(as defined in \fI<linux/prctl.h>\fP). -The -.I arg4 -argument should provide the size of the struct. -.IP -This feature is available only if the kernel is built with the -.B CONFIG_CHECKPOINT_RESTORE -option enabled. -.TP -.B PR_SET_MM_MAP_SIZE -Returns the size of the -.I struct prctl_mm_map -the kernel expects. -This allows user space to find a compatible struct. -The -.I arg3 -argument should be a pointer to an unsigned int. -.IP -This feature is available only if the kernel is built with the -.B CONFIG_CHECKPOINT_RESTORE -option enabled. -.RE +.TQ +.B PR_SET_MM .\" prctl PR_SET_VMA .TP .BR PR_SET_VMA " (since Linux 5.17)" @@ -1619,38 +1442,6 @@ attribute (see the discussion of .B PR_SET_NO_NEW_PRIVS above). .TP -.B EACCES -.I op -is -.BR PR_SET_MM , -and -.I arg2 -is -.BR PR_SET_MM_EXE_FILE , -the file is not executable. -.TP -.B EBADF -.I op -is -.BR PR_SET_MM , -.I arg2 -is -.BR PR_SET_MM_EXE_FILE , -and the file descriptor passed in -.I arg3 -is not valid. -.TP -.B EBUSY -.I op -is -.BR PR_SET_MM , -.I arg2 -is -.BR PR_SET_MM_EXE_FILE , -and this the second attempt to change the -.IR /proc/ pid /exe -symbolic link, which is prohibited. -.TP .B EFAULT .I arg2 is an invalid address. @@ -1712,41 +1503,6 @@ and the kernel was not configured with .B EINVAL .I op is -.BR PR_SET_MM , -and one of the following is true -.RS -.IP \[bu] 3 -.I arg3 -is greater than -.B TASK_SIZE -(the limit on the size of the user address space for this architecture); -.IP \[bu] -.I arg2 -is -.BR PR_SET_MM_START_CODE , -.BR PR_SET_MM_END_CODE , -.BR PR_SET_MM_START_DATA , -.BR PR_SET_MM_END_DATA , -or -.BR PR_SET_MM_START_STACK , -and the permissions of the corresponding memory area are not as required; -.IP \[bu] -.I arg2 -is -.B PR_SET_MM_START_BRK -or -.BR PR_SET_MM_BRK , -and -.I arg3 -is less than or equal to the end of the data segment -or specifies a value that would cause the -.B RLIMIT_DATA -resource limit to be exceeded. -.RE -.TP -.B EINVAL -.I op -is .B PR_SET_PTRACER and .I arg2 @@ -1883,14 +1639,6 @@ wherein the speculation was disabled with .B PR_SPEC_FORCE_DISABLE and caller tried to enable it again. .TP -.B EPERM -.I op -is -.BR PR_SET_MM , -and the caller does not have the -.B CAP_SYS_RESOURCE -capability. -.TP .B ERANGE .I op was @@ -1948,4 +1696,5 @@ glibc 2.0.6 .BR PR_GET_KEEPCAPS (2const), .BR PR_MCE_KILL (2const), .BR PR_MCE_KILL_GET (2const), +.BR PR_SET_MM (2const), .BR core (5) |