Re: [PATCH] proc.5, core.5: clarify suid_dumpable vs core_pattern

In 3.6, additional requirements were placed on core_pattern when
suid_dumpable is set to 2. Document this and include commit references.

Signed-off-by: Kees Cook <redacted>
---
 man5/core.5 |    8 ++++++++
 man5/proc.5 |    7 +++++++
 2 files changed, 15 insertions(+)

diff --git a/man5/core.5 b/man5/core.5
index 379082d..1d527b7 100644
--- a/man5/core.5
+++ b/man5/core.5

@@ -176,6 +176,14 @@ file contains the value 0, then a core dump file is simply named
 If this file contains a nonzero value, then the core dump file includes
 the process ID in a name of the form
 .IR core.PID .
+
+Since version 3.6,
+.\" 9520628e8ceb69fa9a4aee6b57f22675d9e1b709
+if
+.I /proc/sys/fs/suid_dumpable
+is set to 2 ("suidsafe"), the pattern must be either a fully qualified path
+(starting with a leading \(aq/\(aq character) or a pipe, as defined below.
+

 .SS Piping core dumps to a program
 Since kernel 2.6.19, Linux supports an alternate syntax for the
 .I /proc/sys/kernel/core_pattern

diff --git a/man5/proc.5 b/man5/proc.5
index c29eacc..940c1fa 100644
--- a/man5/proc.5
+++ b/man5/proc.5

@@ -2481,6 +2481,13 @@ For security reasons core dumps in this mode will not overwrite one
 another or other files.
 This mode is appropriate when administrators are
 attempting to debug problems in a normal environment.
+Additionally, since Linux 3.6,
+.\" 9520628e8ceb69fa9a4aee6b57f22675d9e1b709
+.I /proc/sys/kernel/core_pattern
+must either be a fully-qualified path, or a pipe command, as detailed in
+.BR core (5).
+Warnings will be emitted to the kernel syslog about disallowed combinations.