kernel: mtdsplit_uimage: use separated buffer for reading data

We shouldn't read data directly into the header struct, as some devices
(e.g. Edimax) need more bytes due to some extra header.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
git-svn-id: svn://svn.openwrt.org/openwrt/trunk@44414 3c298f89-4303-0410-b956-a3cf2f4a3e73

diff --git a/target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit_uimage.c b/target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit_uimage.c
index 04a0eb4..eb4729a 100644 (file)
--- a/target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit_uimage.c
+++ b/target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit_uimage.c
@@ -49,15 +49,15 @@ struct uimage_header {
 
 static int
 read_uimage_header(struct mtd_info *mtd, size_t offset,
-                  struct uimage_header *header)
+                  u_char *buf)
 {
+       struct uimage_header *header;
        size_t header_len;
        size_t retlen;
        int ret;
 
        header_len = sizeof(*header);
-       ret = mtd_read(mtd, offset, header_len, &retlen,
-                      (unsigned char *) header);
+       ret = mtd_read(mtd, offset, header_len, &retlen, buf);
        if (ret) {
                pr_debug("read error in \"%s\"\n", mtd->name);
                return ret;
@@ -83,6 +83,7 @@ static int __mtdsplit_parse_uimage(struct mtd_info *master,
                                   ssize_t (*find_header)(u_char *buf, size_t len))
 {
        struct mtd_partition *parts;
+       u_char *buf;
        struct uimage_header *header;
        int nr_parts;
        size_t offset;
@@ -98,8 +99,8 @@ static int __mtdsplit_parse_uimage(struct mtd_info *master,
        if (!parts)
                return -ENOMEM;
 
-       header = vmalloc(sizeof(*header));
-       if (!header) {
+       buf = vmalloc(sizeof(*header));
+       if (!buf) {
                ret = -ENOMEM;
                goto err_free_parts;
        }
@@ -108,20 +109,17 @@ static int __mtdsplit_parse_uimage(struct mtd_info *master,
        for (offset = 0; offset < master->size; offset += master->erasesize) {
                uimage_size = 0;
 
-               ret = read_uimage_header(master, offset, header);
+               ret = read_uimage_header(master, offset, buf);
                if (ret)
                        continue;
 
-               ret = find_header((u_char *)header, sizeof(*header));
+               ret = find_header(buf, sizeof(*buf));
                if (ret < 0) {
                        pr_debug("no valid uImage found in \"%s\" at offset %llx\n",
                                 master->name, (unsigned long long) offset);
                        continue;
                }
-               if (ret > 0) {
-                       pr_warn("extra header offsets are not supported yet\n");
-                       continue;
-               }
+               header = (struct uimage_header *)(buf + ret);
 
                uimage_size = sizeof(*header) + be32_to_cpu(header->ih_size);
                if ((offset + uimage_size) > master->size) {
@@ -135,7 +133,7 @@ static int __mtdsplit_parse_uimage(struct mtd_info *master,
        if (uimage_size == 0) {
                pr_debug("no uImage found in \"%s\"\n", master->name);
                ret = -ENODEV;
-               goto err_free_header;
+               goto err_free_buf;
        }
 
        uimage_offset = offset;
@@ -152,7 +150,7 @@ static int __mtdsplit_parse_uimage(struct mtd_info *master,
                if (ret) {
                        pr_debug("no rootfs after uImage in \"%s\"\n",
                                 master->name);
-                       goto err_free_header;
+                       goto err_free_buf;
                }
 
                rootfs_size = master->size - rootfs_offset;
@@ -166,7 +164,7 @@ static int __mtdsplit_parse_uimage(struct mtd_info *master,
                if (ret) {
                        pr_debug("no rootfs before uImage in \"%s\"\n",
                                 master->name);
-                       goto err_free_header;
+                       goto err_free_buf;
                }
 
                rootfs_offset = 0;
@@ -176,7 +174,7 @@ static int __mtdsplit_parse_uimage(struct mtd_info *master,
        if (rootfs_size == 0) {
                pr_debug("no rootfs found in \"%s\"\n", master->name);
                ret = -ENODEV;
-               goto err_free_header;
+               goto err_free_buf;
        }
 
        parts[uimage_part].name = KERNEL_PART_NAME;
@@ -187,13 +185,13 @@ static int __mtdsplit_parse_uimage(struct mtd_info *master,
        parts[rf_part].offset = rootfs_offset;
        parts[rf_part].size = rootfs_size;
 
-       vfree(header);
+       vfree(buf);
 
        *pparts = parts;
        return nr_parts;
 
-err_free_header:
-       vfree(header);
+err_free_buf:
+       vfree(buf);
 
 err_free_parts:
        kfree(parts);