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Diffstat (limited to 'lib/reed_solomon/decode_rs.c')
-rw-r--r--lib/reed_solomon/decode_rs.c18
1 files changed, 14 insertions, 4 deletions
diff --git a/lib/reed_solomon/decode_rs.c b/lib/reed_solomon/decode_rs.c
index 0ec3f257ffdf..a5d313381539 100644
--- a/lib/reed_solomon/decode_rs.c
+++ b/lib/reed_solomon/decode_rs.c
@@ -42,8 +42,18 @@
BUG_ON(pad < 0 || pad >= nn);
/* Does the caller provide the syndrome ? */
- if (s != NULL)
- goto decode;
+ if (s != NULL) {
+ for (i = 0; i < nroots; i++) {
+ /* The syndrome is in index form,
+ * so nn represents zero
+ */
+ if (s[i] != nn)
+ goto decode;
+ }
+
+ /* syndrome is zero, no errors to correct */
+ return 0;
+ }
/* form the syndromes; i.e., evaluate data(x) at roots of
* g(x) */
@@ -99,9 +109,9 @@
if (no_eras > 0) {
/* Init lambda to be the erasure locator polynomial */
lambda[1] = alpha_to[rs_modnn(rs,
- prim * (nn - 1 - eras_pos[0]))];
+ prim * (nn - 1 - (eras_pos[0] + pad)))];
for (i = 1; i < no_eras; i++) {
- u = rs_modnn(rs, prim * (nn - 1 - eras_pos[i]));
+ u = rs_modnn(rs, prim * (nn - 1 - (eras_pos[i] + pad)));
for (j = i + 1; j > 0; j--) {
tmp = index_of[lambda[j - 1]];
if (tmp != nn) {