git: e32d04bed890 - stable/12 - awk: Fix subobject out-of-bounds access

[Warner Losh]

The branch stable/12 has been updated by imp:

URL: https://cgit.FreeBSD.org/src/commit/?id=e32d04bed89057c54147db931fa544bb601f48ac

commit e32d04bed89057c54147db931fa544bb601f48ac
Author:     Alex Richardson <arichardson at FreeBSD.org>
AuthorDate: 2020-09-21 19:03:07 +0000
Commit:     Warner Losh <imp at FreeBSD.org>
CommitDate: 2021-07-10 17:11:15 +0000

    awk: Fix subobject out-of-bounds access
    
    When matching a regex with ^, it would attempt to access
    gototab[NSTATES][NCHARS+2], and therefore access the state for the \002
    character instead. This change is required to run awk under CHERI (with
    sub-object bounds) and when running with UBSan instrumentation.
    
    This was committed upstream as https://github.com/onetrueawk/awk/commit/cbf924342b63a095a4c6842280c3085b1b63ae45
    
    Found by:       CHERI (with subobject bounds enabled)
    Obtained from:  CheriBSD
    Reviewed By:    imp
    Differential Revision: https://reviews.freebsd.org/D26509
    
    (cherry picked from commit ae692c42cb46a5e72772070070840b15dd5d6bd8)
---
 contrib/one-true-awk/awk.h | 4 +++-
 contrib/one-true-awk/b.c   | 2 --
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/contrib/one-true-awk/awk.h b/contrib/one-true-awk/awk.h
index b16c2f36f828..31d070aecddc 100644
--- a/contrib/one-true-awk/awk.h
+++ b/contrib/one-true-awk/awk.h
@@ -218,6 +218,8 @@ extern	int	pairstack[], paircnt;
 #define NCHARS	(256+3)		/* 256 handles 8-bit chars; 128 does 7-bit */
 				/* watch out in match(), etc. */
 #define NSTATES	32
+#define	HAT	(NCHARS+2)	/* matches ^ in regular expr */
+				/* NCHARS is 2**n */
 
 typedef struct rrow {
 	long	ltype;	/* long avoids pointer warnings on 64-bit */
@@ -230,7 +232,7 @@ typedef struct rrow {
 } rrow;
 
 typedef struct fa {
-	uschar	gototab[NSTATES][NCHARS];
+	uschar	gototab[NSTATES][HAT + 1];
 	uschar	out[NSTATES];
 	uschar	*restr;
 	int	*posns[NSTATES];
diff --git a/contrib/one-true-awk/b.c b/contrib/one-true-awk/b.c
index 4de746fa087f..0cdcf30a972e 100644
--- a/contrib/one-true-awk/b.c
+++ b/contrib/one-true-awk/b.c
@@ -37,8 +37,6 @@ __FBSDID("$FreeBSD$");
 #include "awk.h"
 #include "ytab.h"
 
-#define	HAT	(NCHARS+2)	/* matches ^ in regular expr */
-				/* NCHARS is 2**n */
 #define MAXLIN 22
 
 #define type(v)		(v)->nobj	/* badly overloaded here */