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Re: [PATCH][BZ #17657] Return allocated array instead array on stack.
- From: OndÅej BÃlka <neleai at seznam dot cz>
- To: Andreas Schwab <schwab at suse dot de>
- Cc: libc-alpha at sourceware dot org
- Date: Wed, 10 Dec 2014 16:13:34 +0100
- Subject: Re: [PATCH][BZ #17657] Return allocated array instead array on stack.
- Authentication-results: sourceware.org; auth=none
- References: <20141210132153 dot GA6395 at domone> <mvmppbrtx3i dot fsf at hawking dot suse dot de> <20141210143252 dot GA27265 at domone> <mvmbnnbtv76 dot fsf at hawking dot suse dot de>
On Wed, Dec 10, 2014 at 03:50:53PM +0100, Andreas Schwab wrote:
> OndÅej BÃlka <neleai@seznam.cz> writes:
>
> > On Wed, Dec 10, 2014 at 03:09:53PM +0100, Andreas Schwab wrote:
> >> OndÅej BÃlka <neleai@seznam.cz> writes:
> >>
> >> > here we return array on stack which is invalid. OK to fix it in obvious way?
> >>
> >> The obvious way would be a static allocation.
> >>
> > which breaks when user modifies array.
>
> Which user?
>
I meant caller, as I looked at code more caller cannot modify it so
static allocation is ok. Also found second occurence of same problem.
[BZ #17657]
* locale/programs/ld-ctype.c (find_translit2, read_widestring): Return
static array.
diff --git a/locale/programs/ld-ctype.c b/locale/programs/ld-ctype.c
index 67846b3..eeaf645 100644
--- a/locale/programs/ld-ctype.c
+++ b/locale/programs/ld-ctype.c
@@ -114,6 +114,9 @@ struct translit_include_t
struct translit_include_t *next;
};
+/* Provide some dummy pointer for empty string. */
+static uint32_t no_str[] = { 0 };
+
/* Sparse table of uint32_t. */
#define TABLE idx_table
@@ -1777,7 +1780,7 @@ find_translit2 (struct locale_ctype_t *ctype, const struct charmap_t *charmap,
for (wi = tirunp->from; wi <= wch; wi += tirunp->step)
if (wi == wch)
- return (uint32_t []) { 0 };
+ return no_str;
}
}
@@ -1831,7 +1834,7 @@ read_widestring (struct linereader *ldfile, struct token *now,
if (now->tok == tok_default_missing)
/* The special name "" will denote this case. */
- wstr = ((uint32_t *) { 0 });
+ wstr = no_str;
else if (now->tok == tok_bsymbol)
{
/* Get the value from the repertoire. */
@@ -4090,9 +4093,6 @@ allocate_arrays (struct locale_ctype_t *ctype, const struct charmap_t *charmap,
}
else
{
- /* Provide some dummy pointers since we have nothing to write out. */
- static uint32_t no_str = { 0 };
-
ctype->translit_from_idx = &no_str;
ctype->translit_from_tbl = &no_str;
ctype->translit_to_tbl = &no_str;