TEXTSEARCH: Fix Boyer Moore initialization bug

[TEXTSEARCH]: Fix Boyer Moore initialization bug

The pattern is set after trying to compute the prefix table, which tries
to use it. Initialize it before calling compute_prefix_tbl, make
compute_prefix_tbl consistently use only the data from struct ts_bm
and remove the now unnecessary arguments.

Signed-off-by: Michael Rash <mbr@cipherdyne.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Acked-by: David Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/lib/ts_bm.c b/lib/ts_bm.c
index c4c1ac5fbd1aea372553ce094171ff8c152b2433..791726579daaea9d9a641c9efb7c3e9597a106c3 100644 (file)
--- a/lib/ts_bm.c
+++ b/lib/ts_bm.c
@@ -112,15 +112,14 @@ static int subpattern(u8 *pattern, int i, int j, int g)
        return ret;
 }
 
-static void compute_prefix_tbl(struct ts_bm *bm, const u8 *pattern,
-                              unsigned int len)
+static void compute_prefix_tbl(struct ts_bm *bm)
 {
        int i, j, g;
 
        for (i = 0; i < ASIZE; i++)
-               bm->bad_shift[i] = len;
-       for (i = 0; i < len - 1; i++)
-               bm->bad_shift[pattern[i]] = len - 1 - i;
+               bm->bad_shift[i] = bm->patlen;
+       for (i = 0; i < bm->patlen - 1; i++)
+               bm->bad_shift[bm->pattern[i]] = bm->patlen - 1 - i;
 
        /* Compute the good shift array, used to match reocurrences 
         * of a subpattern */
@@ -151,8 +150,8 @@ static struct ts_config *bm_init(const void *pattern, unsigned int len,
        bm = ts_config_priv(conf);
        bm->patlen = len;
        bm->pattern = (u8 *) bm->good_shift + prefix_tbl_len;
-       compute_prefix_tbl(bm, pattern, len);
        memcpy(bm->pattern, pattern, len);
+       compute_prefix_tbl(bm);
 
        return conf;
 }