[U-Boot] [PATCH] fs: ext4: Fix journal overrun issue reported by Coverity

[Brüns, Stefan]

On Montag, 21. August 2017 04:30:15 CEST Tom Rini wrote:
> While &p_jdb[fs->blksz] is a valid expression (it points *one* char
> sized element past the end of the array, e.g. &p_jdb[fs->blksz + 1] is
> invalid (according to the C standard (C99/C11)).
> 
> Changing this to tag = (struct ext3_journal_block_tag *)(p_jdb + ofs);
> 
> Cc: Stefan Brüns <stefan.bruens at rwth-aachen.de>
> Suggested-by: Stefan Brüns <stefan.bruens at rwth-aachen.de>
> Reported-by: Coverity (CID: 165117, 165110)
> Signed-off-by: Tom Rini <trini at konsulko.com>
> ---
> Stefan, since this is your suggestion and message, if you want me to v2
> with you as Author, I'd be quite happy to, thanks again!

Hi Tom,

whatever you like, both is fine with me.

Kind regards,

Stefan

PS:
Reviewed-by: Stefan Brüns <stefan.bruens at rwth-aachen.de>

> ---
>  fs/ext4/ext4_journal.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/fs/ext4/ext4_journal.c b/fs/ext4/ext4_journal.c
> index 5a25be4c8ac2..fed6287eac45 100644
> --- a/fs/ext4/ext4_journal.c
> +++ b/fs/ext4/ext4_journal.c
> @@ -355,7 +355,7 @@ void recover_transaction(int prev_desc_logical_no)
>  	ofs = sizeof(struct journal_header_t);
> 
>  	do {
> -		tag = (struct ext3_journal_block_tag *)&p_jdb[ofs];
> +		tag = (struct ext3_journal_block_tag *)(p_jdb + ofs);
>  		ofs += sizeof(struct ext3_journal_block_tag);
> 
>  		if (ofs > fs->blksz)
> @@ -466,7 +466,7 @@ int ext4fs_check_journal_state(int recovery_flag)
>  			ofs = sizeof(struct journal_header_t);
>  			do {
>  				tag = (struct ext3_journal_block_tag *)
> -				    &p_jdb[ofs];
> +				    (p_jdb + ofs);
>  				ofs += sizeof(struct ext3_journal_block_tag);
>  				if (ofs > fs->blksz)
>  					break;