From: "Daniel P. Berrange" <berra...@redhat.com>
The sheepdog driver declares an instance of BDRVSheepdogState
in the stack. This struct is 4 MB in size. While the default
Linux stack size may be 10 MB, we should not assume that since
QEMU needs to be portable to other OS.
block/sheepdog.c: In function ‘sd_create’:
block/sheepdog.c:1240:1: error: the frame size of 4199888 bytes is larger than
131072 bytes [-Werror=frame-larger-than=]
* block/sheepdog.c: Allow BDRVSheepdogState on the heap
instead of stack
* configure: Add -Wframe-larger-than to validate stack
size does not exceed 128k
Signed-off-by: Daniel P. Berrange <berra...@redhat.com>
---
block/sheepdog.c | 43 ++++++++++++++++++++++++++-----------------
configure | 1 +
2 files changed, 27 insertions(+), 17 deletions(-)
diff --git a/block/sheepdog.c b/block/sheepdog.c
index 00276f6f..ff6f3d2 100644
--- a/block/sheepdog.c
+++ b/block/sheepdog.c
@@ -1163,20 +1163,22 @@ static int sd_create(const char *filename,
QEMUOptionParameter *options)
uint32_t vid = 0, base_vid = 0;
int64_t vdi_size = 0;
char *backing_file = NULL;
- BDRVSheepdogState s;
+ BDRVSheepdogState *s1;
char vdi[SD_MAX_VDI_LEN], tag[SD_MAX_VDI_TAG_LEN];
uint32_t snapid;
int prealloc = 0;
const char *vdiname;
+ int rv = -EINVAL;
+
+ s1 = g_new0(BDRVSheepdogState, 1);
strstart(filename, "sheepdog:", &vdiname);
- memset(&s, 0, sizeof(s));
memset(vdi, 0, sizeof(vdi));
memset(tag, 0, sizeof(tag));
- if (parse_vdiname(&s, vdiname, vdi, &snapid, tag) < 0) {
+ if (parse_vdiname(s1, vdiname, vdi, &snapid, tag) < 0) {
error_report("invalid filename");
- return -EINVAL;
+ goto cleanup;
}
while (options && options->name) {
@@ -1192,7 +1194,7 @@ static int sd_create(const char *filename,
QEMUOptionParameter *options)
} else {
error_report("Invalid preallocation mode: '%s'",
options->value.s);
- return -EINVAL;
+ goto cleanup;
}
}
options++;
@@ -1200,43 +1202,50 @@ static int sd_create(const char *filename,
QEMUOptionParameter *options)
if (vdi_size > SD_MAX_VDI_SIZE) {
error_report("too big image size");
- return -EINVAL;
+ goto cleanup;
}
if (backing_file) {
BlockDriverState *bs;
- BDRVSheepdogState *s;
+ BDRVSheepdogState *s2;
BlockDriver *drv;
/* Currently, only Sheepdog backing image is supported. */
drv = bdrv_find_protocol(backing_file);
if (!drv || strcmp(drv->protocol_name, "sheepdog") != 0) {
error_report("backing_file must be a sheepdog image");
- return -EINVAL;
+ goto cleanup;
}
ret = bdrv_file_open(&bs, backing_file, 0);
- if (ret < 0)
- return -EIO;
+ if (ret < 0) {
+ rv = -EIO;
+ goto cleanup;
+ }
- s = bs->opaque;
+ s2 = bs->opaque;
- if (!is_snapshot(&s->inode)) {
+ if (!is_snapshot(&s2->inode)) {
error_report("cannot clone from a non snapshot vdi");
bdrv_delete(bs);
- return -EINVAL;
+ goto cleanup;
}
- base_vid = s->inode.vdi_id;
+ base_vid = s2->inode.vdi_id;
bdrv_delete(bs);
}
- ret = do_sd_create(vdi, vdi_size, base_vid, &vid, 0, s.addr, s.port);
+ ret = do_sd_create(vdi, vdi_size, base_vid, &vid, 0, s1->addr, s1->port);
if (!prealloc || ret) {
- return ret;
+ rv = ret;
+ goto cleanup;
}
- return sd_prealloc(filename);
+ rv = sd_prealloc(filename);
+
+ cleanup:
+ g_free(s1);
+ return rv;
}
static void sd_close(BlockDriverState *bs)
diff --git a/configure b/configure
index 44b28c8..28b5dd5 100755
--- a/configure
+++ b/configure
@@ -1165,6 +1165,7 @@ gcc_flags="$gcc_flags -Wmissing-include-dirs"
gcc_flags="$gcc_flags -Wempty-body"
gcc_flags="$gcc_flags -Wnested-externs"
gcc_flags="$gcc_flags -Wendif-labels"
+gcc_flags="$gcc_flags -Wframe-larger-than=131072"
cat > $TMPC << EOF
int main(void) { return 0; }
EOF
--
1.7.7.6
