Messages in this thread | | | Date | Fri, 27 Aug 2010 15:15:15 -0500 | Subject | Re: [PATCH] scatterlist: prevent invalid free when alloc fails | From | Jeffrey Carlyle <> |
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On Fri, Aug 27, 2010 at 2:45 PM, Jeffrey Carlyle <jeff.carlyle@motorola.com> wrote: > On Fri, Aug 27, 2010 at 5:18 AM, Tejun Heo <tj@kernel.org> wrote: >> On 08/26/2010 06:04 PM, Jeffrey Carlyle wrote: >>> diff --git a/lib/scatterlist.c b/lib/scatterlist.c >>> index a5ec428..acf2c6e 100644 >>> --- a/lib/scatterlist.c >>> +++ b/lib/scatterlist.c >>> @@ -163,7 +163,7 @@ void __sg_free_table(struct sg_table *table, >>> unsigned int max_ents, >>> return; >>> >>> sgl = table->sgl; >>> - while (table->orig_nents) { >>> + while (table->orig_nents && sgl) { >>> unsigned int alloc_size = table->orig_nents; >>> unsigned int sg_size; >> >> Why is this change necessary? > > Well the problem we were seeing manifested itself when we called > free_fn on a NULL value. This was a naive attempt at avoiding that. If > the logic in __sg_alloc_table is corrected, I agree that we shouldn't > need this.
Actually, please disregard the comment about trying to free NULL. I don't think we need to add the "&& sgl" under any circumstances. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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