[Skiboot] [PATCH] libflash: check ffs_part_info return value in ffs_init

[Cyril Bur]

On Tue, 28 Jul 2015 11:07:59 +0800
Jeremy Kerr <jk at ozlabs.org> wrote:

> Current build fail for me, with:
> 
>      CC  libffs.o
>  ../../libflash/libffs.c: In function ‘ffs_init’:
>  ../../libflash/libffs.c:149:8: error: ‘start’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
>       rc = blocklevel_ecc_protect(bl, start, total_size);
>          ^
>  ../../libflash/libffs.c:149:8: error: ‘total_size’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
>  ../../libflash/libffs.c:148:7: error: ‘ecc’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
>      if (ecc) {
>         ^
>  cc1: all warnings being treated as errors
> 
> This is because we're not checking for the return value of
> ffs_part_info, which may return with start/total_size/ecc uninitialised.
> 
Thanks Jeremy,

Was this `make check`? I'm surprised I didn't hit those.

> Signed-off-by: Jeremy Kerr <jk at ozlabs.org>
Reviewed-by: Cyril Bur <cyril.bur at au1.ibm.com>
> 
> ---
>  libflash/libffs.c |    8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/libflash/libffs.c b/libflash/libffs.c
> index 0164071..3010a61 100644
> --- a/libflash/libffs.c
> +++ b/libflash/libffs.c
> @@ -144,7 +144,13 @@ int ffs_init(uint32_t offset, uint32_t max_size, struct blocklevel_device *bl,
>  		uint32_t start, total_size;
>  		bool ecc;
>  		for (i = 0; i < f->hdr.entry_count; i++) {
> -			ffs_part_info(f, i, NULL, &start, &total_size, NULL, &ecc);
> +			rc = ffs_part_info(f, i, NULL, &start, &total_size,
> +					NULL, &ecc);
> +			if (rc) {
> +				FL_ERR("FFS: Failed to read ffs partition %d\n",
> +						i);
> +				goto out;
> +			}
>  			if (ecc) {
>  				rc = blocklevel_ecc_protect(bl, start, total_size);
>  				if (rc) {