diff --git a/lib/842/842_decompress.c b/lib/842/842_decompress.c
index 582085ef8b49..87d1e0f8a492 100644
--- a/lib/842/842_decompress.c
+++ b/lib/842/842_decompress.c
@@ -165,6 +165,9 @@ static int __do_index(struct sw842_param *p, u8 size, u8 bits, u64 fsize)
 	u64 index, offset, total = round_down(p->out - p->ostart, 8);
 	int ret;
 
+	if (size > p->olen)
+		return -ENOSPC;
+
 	ret = next_bits(p, &index, bits);
 	if (ret)
 		return ret;
@@ -344,6 +347,8 @@ int sw842_decompress(const u8 *in, unsigned int ilen,
 
 			if (!bytes || bytes > SHORT_DATA_BITS_MAX)
 				return -EINVAL;
+			if (bytes > p.olen)
+				return -ENOSPC;
 
 			while (bytes-- > 0) {
 				ret = next_bits(&p, &tmp, 8);