Hi,

This patch gives a build error:

hexedit.c:1500: error: incompatible type for argument 1 of ‘memset’

On 17/06/09 17:00, Jim Meyering wrote:
> If the malloc of more_indir fails, the subsequent deref
> via memset would cause a segfault.
> 
> I chose to avoid that by making more_indir a stack-local.
> If it's 512-byte size is too big for your stack
> requirements, let me know and I'll rewrite to
> use malloc -- though doing it that way (and taking
> care to avoid leaks), would probably end up uglier.
> 
>>From fda0f39b0389088b0ea66216aed21d4f5f1bb604 Mon Sep 17 00:00:00 2001
> From: Jim Meyering <[email protected]>
> Date: Wed, 17 Jun 2009 16:54:03 +0200
> Subject: [PATCH] hexedit: avoid NULL dereference upon failed malloc
> 
> * gfs2/edit/hexedit.c (display_indirect): Avoid unchecked malloc
> by declaring more_indir on the stack.
> ---
>  gfs2/edit/hexedit.c |   12 +++++-------
>  1 files changed, 5 insertions(+), 7 deletions(-)
> 
> diff --git a/gfs2/edit/hexedit.c b/gfs2/edit/hexedit.c
> index e8c6030..84b4be4 100644
> --- a/gfs2/edit/hexedit.c
> +++ b/gfs2/edit/hexedit.c
> @@ -1477,13 +1477,12 @@ static int display_indirect(struct iinfo *ind, int 
> indblocks, int level, uint64_
>                       file_offset = 0;
>               if (!termlines && ((level + 1 < di.di_height) ||
>                                  (S_ISDIR(di.di_mode) && !level))) {
> -                     struct iinfo *more_indir;
>                       int more_ind;
>                       char *tmpbuf;
>                       
> -                     more_indir = malloc(sizeof(struct iinfo));
>                       tmpbuf = malloc(sbd.bsize);
>                       if (tmpbuf) {
> +                             struct iinfo more_indir;
>                               lseek(sbd.device_fd,
>                                     ind->ii[pndx].block * sbd.bsize,
>                                     SEEK_SET);
> @@ -1500,18 +1499,17 @@ static int display_indirect(struct iinfo *ind, int 
> indblocks, int level, uint64_
>                               }
>                               memset(more_indir, 0, sizeof(struct iinfo));
>                               if (S_ISDIR(di.di_mode)) {
> -                                     do_leaf_extended(tmpbuf, more_indir);
> -                                     display_leaf(more_indir);
> +                                     do_leaf_extended(tmpbuf, &more_indir);
> +                                     display_leaf(&more_indir);
>                               } else {
>                                       more_ind = do_indirect_extended(tmpbuf,
> -                                                                     
> more_indir);
> -                                     display_indirect(more_indir,
> +                                                                     
> &more_indir);
> +                                     display_indirect(&more_indir,
>                                                        more_ind, level + 1,
>                                                        file_offset);
>                               }
>                               free(tmpbuf);
>                       }
> -                     free(more_indir);
>               }
>               print_entry_ndx = pndx; /* restore after recursion */
>               eol(0);

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