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D42107.diff

diff --git a/share/man/man7/mitigations.7 b/share/man/man7/mitigations.7
--- a/share/man/man7/mitigations.7
+++ b/share/man/man7/mitigations.7
@@ -25,7 +25,7 @@
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
-.Dd October 5, 2023
+.Dd October 6, 2023
.Dt MITIGATIONS 7
.Os
.Sh NAME
@@ -50,10 +50,10 @@
Write XOR Execute page protection policy
.It
.Dv PROT_MAX
-".It
-"Read-Only Relocation (RELRO)
-.\".It
-.\"Bind Now
+.It
+Relocation Read-Only (RELRO)
+.It
+Bind Now
.\".It
.\"Stack Smashing Protection (SSP)
.\".It
@@ -192,8 +192,25 @@
.Xr mprotect
call, but may not be made executable.
.\"
-.\".Ss Read-Only Relocation (RELRO)
-.\"
+.Ss Relocation Read-Only (RELRO)
+Relocation Read-Only (RELRO) is a mitigation tool that makes certain portions
+of a program's address space that contain ELF metadata read-only, after
+relocation processing by
+.Xr rtld 1 .
+.Pp
+When enabled in isolation the RELRO option provides
+.Em partial RELRO
+support.
+In this case the Procedure Linkage Table (PLT)-related part of the
+Global Offset Table (GOT) (in the section typically named .got.plt) remains
+writable.
+.Pp
+RELRO is enabled by default.
+The
+.Xr src.conf 5
+build-time option
+.Va WITHOUT_RELRO
+may be used to disable it.
.Ss BIND_NOW
The
.Va WITH_BIND_NOW
@@ -205,11 +222,12 @@
.Xr rtld 1
will then perform all relocation processing when the process starts, instead of
on demand (on the first access to each symbol).
+.Pp
When enabled in combination with
.Dv RELRO
(which is enabled by default) this provides
-.Qt full
-RELRO, the entire GOT (.got and .got.plt) are made read-only at program startup,
+.Em full RELRO .
+The entire GOT (.got and .got.plt) are made read-only at program startup,
preventing attacks on the relocation table.
Note that this results in a nonstandard Application Binary Interface (ABI),
and it is possible that some applications may not function correctly.

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