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-rw-r--r--Documentation/sysctl/fs.txt36
-rw-r--r--Documentation/sysctl/kernel.txt29
-rw-r--r--Documentation/sysctl/vm.txt25
3 files changed, 87 insertions, 3 deletions
diff --git a/Documentation/sysctl/fs.txt b/Documentation/sysctl/fs.txt
index 6c00c1e2743f..819caf8ca05f 100644
--- a/Documentation/sysctl/fs.txt
+++ b/Documentation/sysctl/fs.txt
@@ -34,7 +34,9 @@ Currently, these files are in /proc/sys/fs:
- overflowgid
- pipe-user-pages-hard
- pipe-user-pages-soft
+- protected_fifos
- protected_hardlinks
+- protected_regular
- protected_symlinks
- suid_dumpable
- super-max
@@ -182,6 +184,24 @@ applied.
==============================================================
+protected_fifos:
+
+The intent of this protection is to avoid unintentional writes to
+an attacker-controlled FIFO, where a program expected to create a regular
+file.
+
+When set to "0", writing to FIFOs is unrestricted.
+
+When set to "1" don't allow O_CREAT open on FIFOs that we don't own
+in world writable sticky directories, unless they are owned by the
+owner of the directory.
+
+When set to "2" it also applies to group writable sticky directories.
+
+This protection is based on the restrictions in Openwall.
+
+==============================================================
+
protected_hardlinks:
A long-standing class of security issues is the hardlink-based
@@ -202,6 +222,22 @@ This protection is based on the restrictions in Openwall and grsecurity.
==============================================================
+protected_regular:
+
+This protection is similar to protected_fifos, but it
+avoids writes to an attacker-controlled regular file, where a program
+expected to create one.
+
+When set to "0", writing to regular files is unrestricted.
+
+When set to "1" don't allow O_CREAT open on regular files that we
+don't own in world writable sticky directories, unless they are
+owned by the owner of the directory.
+
+When set to "2" it also applies to group writable sticky directories.
+
+==============================================================
+
protected_symlinks:
A long-standing class of security issues is the symlink-based
diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt
index eded671d55eb..37a679501ddc 100644
--- a/Documentation/sysctl/kernel.txt
+++ b/Documentation/sysctl/kernel.txt
@@ -38,7 +38,9 @@ show up in /proc/sys/kernel:
- hung_task_panic
- hung_task_check_count
- hung_task_timeout_secs
+- hung_task_check_interval_secs
- hung_task_warnings
+- hyperv_record_panic_msg
- kexec_load_disabled
- kptr_restrict
- l2cr [ PPC only ]
@@ -354,7 +356,7 @@ This file shows up if CONFIG_DETECT_HUNG_TASK is enabled.
hung_task_timeout_secs:
-Check interval. When a task in D state did not get scheduled
+When a task in D state did not get scheduled
for more than this value report a warning.
This file shows up if CONFIG_DETECT_HUNG_TASK is enabled.
@@ -363,6 +365,18 @@ Possible values to set are in range {0..LONG_MAX/HZ}.
==============================================================
+hung_task_check_interval_secs:
+
+Hung task check interval. If hung task checking is enabled
+(see hung_task_timeout_secs), the check is done every
+hung_task_check_interval_secs seconds.
+This file shows up if CONFIG_DETECT_HUNG_TASK is enabled.
+
+0 (default): means use hung_task_timeout_secs as checking interval.
+Possible values to set are in range {0..LONG_MAX/HZ}.
+
+==============================================================
+
hung_task_warnings:
The maximum number of warnings to report. During a check interval
@@ -374,6 +388,16 @@ This file shows up if CONFIG_DETECT_HUNG_TASK is enabled.
==============================================================
+hyperv_record_panic_msg:
+
+Controls whether the panic kmsg data should be reported to Hyper-V.
+
+0: do not report panic kmsg data.
+
+1: report the panic kmsg data. This is the default behavior.
+
+==============================================================
+
kexec_load_disabled:
A toggle indicating if the kexec_load syscall has been disabled. This
@@ -440,7 +464,8 @@ Notes:
1) kernel doesn't guarantee, that new object will have desired id. So,
it's up to userspace, how to handle an object with "wrong" id.
2) Toggle with non-default value will be set back to -1 by kernel after
-successful IPC object allocation.
+successful IPC object allocation. If an IPC object allocation syscall
+fails, it is undefined if the value remains unmodified or is reset to -1.
==============================================================
diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt
index 697ef8c225df..7d73882e2c27 100644
--- a/Documentation/sysctl/vm.txt
+++ b/Documentation/sysctl/vm.txt
@@ -27,6 +27,7 @@ Currently, these files are in /proc/sys/vm:
- dirty_bytes
- dirty_expire_centisecs
- dirty_ratio
+- dirtytime_expire_seconds
- dirty_writeback_centisecs
- drop_caches
- extfrag_threshold
@@ -44,6 +45,7 @@ Currently, these files are in /proc/sys/vm:
- mmap_rnd_bits
- mmap_rnd_compat_bits
- nr_hugepages
+- nr_hugepages_mempolicy
- nr_overcommit_hugepages
- nr_trim_pages (only if CONFIG_MMU=n)
- numa_zonelist_order
@@ -178,6 +180,18 @@ The total available memory is not equal to total system memory.
==============================================================
+dirtytime_expire_seconds
+
+When a lazytime inode is constantly having its pages dirtied, the inode with
+an updated timestamp will never get chance to be written out. And, if the
+only thing that has happened on the file system is a dirtytime inode caused
+by an atime update, a worker will be scheduled to make sure that inode
+eventually gets pushed out to disk. This tunable is used to define when dirty
+inode is old enough to be eligible for writeback by the kernel flusher threads.
+And, it is also used as the interval to wakeup dirtytime_writeback thread.
+
+==============================================================
+
dirty_writeback_centisecs
The kernel flusher threads will periodically wake up and write `old' data
@@ -519,6 +533,15 @@ See Documentation/admin-guide/mm/hugetlbpage.rst
==============================================================
+nr_hugepages_mempolicy
+
+Change the size of the hugepage pool at run-time on a specific
+set of NUMA nodes.
+
+See Documentation/admin-guide/mm/hugetlbpage.rst
+
+==============================================================
+
nr_overcommit_hugepages
Change the maximum size of the hugepage pool. The maximum is
@@ -668,7 +691,7 @@ and don't use much of it.
The default value is 0.
See Documentation/vm/overcommit-accounting.rst and
-mm/mmap.c::__vm_enough_memory() for more information.
+mm/util.c::__vm_enough_memory() for more information.
==============================================================
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