libubigen: do not create huge arrays on stack

Stop creating 128KiB and larger arrays on stack - allocate RAM
using malloc() instead.

This patch also teaches libubigen to always set errno.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>

diff --git a/ubi-utils/src/libubigen.c b/ubi-utils/src/libubigen.c
index db58cae4a0aaa107b52204f03956d8dbe44465ee..b090b141112ea2937ddd9205d786c4fbc10275f0 100644 (file)
--- a/ubi-utils/src/libubigen.c
+++ b/ubi-utils/src/libubigen.c
@@ -117,13 +117,19 @@ int ubigen_add_volume(const struct ubigen_info *ui,
        struct ubi_vtbl_record *vtbl_rec = &vtbl[vi->id];
        uint32_t tmp;
 
-       if (vi->id >= ui->max_volumes)
-               return errmsg("too high volume id %d, max. volumes is %d",
-                             vi->id, ui->max_volumes);
+       if (vi->id >= ui->max_volumes) {
+               errmsg("too high volume id %d, max. volumes is %d",
+                      vi->id, ui->max_volumes);
+               errno = EINVAL;
+               return -1;
+       }
 
-       if (vi->alignment >= ui->leb_size)
-               return errmsg("too large alignment %d, max is %d (LEB size)",
-                             vi->alignment, ui->leb_size);
+       if (vi->alignment >= ui->leb_size) {
+               errmsg("too large alignment %d, max is %d (LEB size)",
+                      vi->alignment, ui->leb_size);
+               errno = EINVAL;
+               return -1;
+       }
 
        memset(vtbl_rec, 0, sizeof(struct ubi_vtbl_record));
        tmp = (vi->bytes + ui->leb_size - 1) / ui->leb_size;
@@ -225,15 +231,31 @@ int ubigen_write_volume(const struct ubigen_info *ui,
                        long long bytes, int in, int out)
 {
        int len = vi->usable_leb_size, rd, lnum = 0;
-       char inbuf[ui->leb_size], outbuf[ui->peb_size];
+       char *inbuf, *outbuf;
 
-       if (vi->id >= ui->max_volumes)
-               return errmsg("too high volume id %d, max. volumes is %d",
-                             vi->id, ui->max_volumes);
+       if (vi->id >= ui->max_volumes) {
+               errmsg("too high volume id %d, max. volumes is %d",
+                      vi->id, ui->max_volumes);
+               errno = EINVAL;
+               return -1;
+       }
 
-       if (vi->alignment >= ui->leb_size)
-               return errmsg("too large alignment %d, max is %d (LEB size)",
-                             vi->alignment, ui->leb_size);
+       if (vi->alignment >= ui->leb_size) {
+               errmsg("too large alignment %d, max is %d (LEB size)",
+                      vi->alignment, ui->leb_size);
+               errno = EINVAL;
+               return -1;
+       }
+
+       inbuf = malloc(ui->leb_size);
+       if (!inbuf)
+               return sys_errmsg("cannot allocate %d bytes of memory",
+                                 ui->leb_size);
+       outbuf = malloc(ui->peb_size);
+       if (!outbuf) {
+               sys_errmsg("cannot allocate %d bytes of memory", ui->peb_size);
+               goto out_free;
+       }
 
        memset(outbuf, 0xFF, ui->data_offs);
        ubigen_init_ec_hdr(ui, (struct ubi_ec_hdr *)outbuf, ec);
@@ -249,8 +271,10 @@ int ubigen_write_volume(const struct ubigen_info *ui,
                l = len;
                do {
                        rd = read(in, inbuf + len - l, l);
-                       if (rd != l)
-                               return sys_errmsg("cannot read %d bytes from the input file", l);
+                       if (rd != l) {
+                               sys_errmsg("cannot read %d bytes from the input file", l);
+                               goto out_free1;
+                       }
 
                        l -= rd;
                } while (l);
@@ -262,13 +286,23 @@ int ubigen_write_volume(const struct ubigen_info *ui,
                memset(outbuf + ui->data_offs + len, 0xFF,
                       ui->peb_size - ui->data_offs - len);
 
-               if (write(out, outbuf, ui->peb_size) != ui->peb_size)
-                       return sys_errmsg("cannot write %d bytes to the output file", ui->peb_size);
+               if (write(out, outbuf, ui->peb_size) != ui->peb_size) {
+                       sys_errmsg("cannot write %d bytes to the output file", ui->peb_size);
+                       goto out_free1;
+               }
 
                lnum += 1;
        }
 
+       free(outbuf);
+       free(inbuf);
        return 0;
+
+out_free1:
+       free(outbuf);
+out_free:
+       free(inbuf);
+       return -1;
 }
 
 /**