Add missing options to minijail(1) manpage

We're missing -I, -L, -n, and -U. Borrowed text mostly from the '-h'
usage output, as well as some code comments, and other man pages.

Also fixup one inconsistency in the -h usage output formatting.

Bug: None
TEST=`man ./minijail0.1`; `minijail0 -h`

Change-Id: Ie5a8313486490243d3382726aed82971aad9a466
Signed-off-by: Brian Norris <briannorris@google.com>

2 files changed, 16 insertions, 1 deletions

diff --git a/minijail0.1 b/minijail0.1
index 8d7e188..685b6a6 100644
--- a/minijail0.1
+++ b/minijail0.1
@@ -51,6 +51,9 @@ Print a help message detailing supported system call names for seccomp_filter.
 (Other direct numbers may be specified if minijail0 is not in sync with the
  host kernel or something like 32/64-bit compatibility issues exist.)
 .TP
+\fB-I\fR
+Run \fIprogram\fR as init (pid 1) inside a new pid namespace (implies \fB-p\fR).
+.TP
 \fB-k <src>,<dest>,<type>[,<flags>]\fR
 Mount \fIsrc\fR, a \fItype\fR filesystem, into the chroot directory at \fIdest\fR, with optional \fIflags\fR.
 .TP
@@ -63,6 +66,11 @@ You very likely don't need this.
 Run inside a new IPC namespace. This option makes the program's System V IPC
 namespace independent.
 .TP
+\fB-L\fR
+Report blocked syscalls to syslog when using seccomp filter. This option will
+force certain syscalls to be allowed in order to achieve this, depending on the
+system.
+.TP
 \fB-m "<uid> <loweruid> <count>[,<uid> <loweruid> <count>]"\fR
 Set the uid mapping of a user namespace (implies \fB-pU\fR). Same arguments as
 \fBnewuidmap(1)\fR. Multiple mappings should be separated by ','.
@@ -71,6 +79,10 @@ Set the uid mapping of a user namespace (implies \fB-pU\fR). Same arguments as
 Set the gid mapping of a user namespace (implies \fB-pU\fR). Same arguments as
 \fBnewgidmap(1)\fR. Multiple mappings should be separated by ','.
 .TP
+\fB-n\fR
+Set the process's \fIno_new_privs\fR bit. See \fBprctl(2)\fR and the kernel
+source file \fIDocumentation/prctl/no_new_privs.txt\fR for more info.
+.TP
 \fB-p\fR
 Run inside a new PID namespace. This option will make it impossible for the
 program to see or affect processes that are not its descendants. This implies
@@ -108,6 +120,9 @@ which should be either 'static' or 'dynamic'.
 Change users to \fIuser\fR, which may be either a user name or a numeric user
 ID.
 .TP
+\fB-U\fR
+Enter a new user namespace (implies \fB-p\fR).
+.TP
 \fB-v\fR
 Run inside a new VFS namespace. This option makes the program's mountpoints
 independent of the rest of the system's.
diff --git a/minijail0.c b/minijail0.c
index f3caeac..300e921 100644
--- a/minijail0.c
+++ b/minijail0.c
@@ -145,7 +145,7 @@ static void usage(const char *progn)
 	       "  -T <type>:  Don't access <program> before execve(2), assume <type> ELF binary.\n"
 	       "              <type> must be 'static' or 'dynamic'.\n"
 	       "  -u <user>:  Change uid to <user>.\n"
-	       "  -U          Enter new user namespace (implies -p).\n"
+	       "  -U:         Enter new user namespace (implies -p).\n"
 	       "  -v:         Enter new mount namespace.\n"
 	       "  -V <file>:  Enter specified mount namespace.\n");
 }