On Wed, Jan 20, 2010 at 1:56 AM, Juan Quintela <quint...@redhat.com> wrote:
> From: Kirill A. Shutemov <kir...@shutemov.name>
>
> CC block/vvfat.o
> cc1: warnings being treated as errors
> block/vvfat.c: In function 'commit_one_file':
> block/vvfat.c:2259: error: ignoring return value of 'ftruncate', declared
> with attribute warn_unused_result
> make: *** [block/vvfat.o] Error 1
> CC block/vvfat.o
> In file included from /usr/include/stdio.h:912,
> from ./qemu-common.h:19,
> from block/vvfat.c:27:
> In function 'snprintf',
> inlined from 'init_directories' at block/vvfat.c:871,
> inlined from 'vvfat_open' at block/vvfat.c:1068:
> /usr/include/bits/stdio2.h:65: error: call to __builtin___snprintf_chk will
> always overflow destination buffer
> make: *** [block/vvfat.o] Error 1
>
> Signed-off-by: Kirill A. Shutemov <kir...@shutemov.name>
> Signed-off-by: Juan Quintela <quint...@redhat.com>
> ---
> block/vvfat.c | 9 +++++++--
> 1 files changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/block/vvfat.c b/block/vvfat.c
> index 063f731..df957e5 100644
> --- a/block/vvfat.c
> +++ b/block/vvfat.c
> @@ -868,7 +868,8 @@ static int init_directories(BDRVVVFATState* s,
> {
> direntry_t* entry=array_get_next(&(s->directory));
> entry->attributes=0x28; /* archive | volume label */
> - snprintf((char*)entry->name,11,"QEMU VVFAT");
> + memcpy(entry->name,"QEMU VVF",8);
> + memcpy(entry->extension,"AT ",3);
> }
Better to use
memcpy(entry->name, "QEMU VVFAT", 11);
memcpy() doesn't check bounds.
> /* Now build FAT, and write back information into directory */
> @@ -2256,7 +2257,11 @@ static int commit_one_file(BDRVVVFATState* s,
> c = c1;
> }
>
> - ftruncate(fd, size);
> + if (ftruncate(fd, size)) {
> + perror("ftruncate()");
> + close(fd);
> + return -4;
> + }
> close(fd);
>
> return commit_mappings(s, first_cluster, dir_index);
> --
> 1.6.5.2
>
>
