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charset=us-ascii Content-Disposition: inline In-Reply-To: <20230410073228.23043-1-jaewon31.kim@samsung.com> X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 6C94F20029 X-Stat-Signature: o4ra4zkfwgnu1qirjc4mt4u9dcwbon66 X-HE-Tag: 1681287780-632269 X-HE-Meta: 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 9M6K5hdH tn4gPPJBTk/VL7vdwVLa4zoyPMnMIS0oRvqtic6cqhHz3tf3aIK27kkZ5zsx5KIWt/gRNUS/rWcYhKTGTfHdA/XP9bCy67KiFmQdb68gzFo0mvu+0nU31rlWRjzSO7RaJhfONXJCd9R9Zx/1VZ/BBC7chR11AkqaM1mVJoDXmMnHFMfcn/FVw5vHBiLn6noXNDoLb5pu39GLM6YIKiipA2zNo2dczt8GHudjBneUd8OyknzfIuVUBJEeH4Yg4uouLJzM43SrZLuaK+bO0qs1q5u3WjhgBPlneg1vF X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Sorry for being late. I know there was some pre-existing discussion around that but I didn't have time to participate. On Mon 10-04-23 16:32:28, Jaewon Kim wrote: > @@ -350,6 +350,9 @@ static struct dma_buf *system_heap_allocate(struct dma_heap *heap, > struct page *page, *tmp_page; > int i, ret = -ENOMEM; > > + if (len / PAGE_SIZE > totalram_pages()) > + return ERR_PTR(-ENOMEM); > + This is an antipattern imho. Check 7661809d493b ("mm: don't allow oversized kvmalloc() calls") how kvmalloc has dealt with a similar issue. totalram_pages doesn't really tell you anything about incorrect users. You might be on a low memory system where the request size is sane normally, it just doesn't fit into memory on that particular machine. > buffer = kzalloc(sizeof(*buffer), GFP_KERNEL); > if (!buffer) > return ERR_PTR(-ENOMEM); > -- > 2.17.1 -- Michal Hocko SUSE Labs