[PATCH 3/5] libselinux: matchpathcon: make filespec table per thread and bound specind

The context array (con_array) that specind indexes is per-thread but
the inode association table (fl_head) is process-wide. Give
each thread its own fl_head to match con_array. There are no in-tree
callers of this deprecated interface and single-threaded callers
will see no change.

Also bounds check specind in matchpathcon_filespec_add() to ensure it
is a valid index previously returned by matchpathcon_index().

Signed-off-by: Stephen Smalley <[email protected]>
---
 libselinux/src/matchpathcon.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/libselinux/src/matchpathcon.c b/libselinux/src/matchpathcon.c
index 80de61a0..9a45dbd5 100644
--- a/libselinux/src/matchpathcon.c
+++ b/libselinux/src/matchpathcon.c
@@ -212,7 +212,7 @@ typedef struct file_spec {
 #define HASH_BITS 16
 #define HASH_BUCKETS (1 << HASH_BITS)
 #define HASH_MASK (HASH_BUCKETS - 1)
-static file_spec_t *fl_head;
+static __thread file_spec_t *fl_head;
 
 /*
  * Try to add an association between an inode and
@@ -227,6 +227,11 @@ int matchpathcon_filespec_add(ino_t ino, int specind, const char *file)
 	int h, ret;
 	struct stat sb;
 
+	if (specind < 0 || specind >= con_array_used) {
+		errno = EINVAL;
+		return -1;
+	}
+
 	if (!fl_head) {
 		fl_head = calloc(HASH_BUCKETS, sizeof(file_spec_t));
 		if (!fl_head)
-- 
2.55.0