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dkim=pass header.d=gnuweeb.org header.s=default header.b=nCir+0wH; spf=pass (imf18.hostedemail.com: domain of ammarfaizi2@gnuweeb.org designates 51.81.211.47 as permitted sender) smtp.mailfrom=ammarfaizi2@gnuweeb.org; dmarc=pass (policy=none) header.from=gnuweeb.org X-Rspamd-Server: rspam04 X-HE-Tag: 1662375113-812527 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: On Mon, 5 Sep 2022 05:10:12 +0200, Oscar Salvador wrote: > +static int page_owner_threshold_show(struct seq_file *p, void *v) > +{ > + seq_printf(p, "%lu\n", threshold); Remove a slipped leading 0x20 space here (before seq_printf()). > + return 0; > +} > + > +static ssize_t write_page_owner_threshold(struct file *file, const char __user *buf, > + size_t count, loff_t *pos) > +{ > + char *kbuf; > + int ret = 0; > + > + count = min_t(size_t, count, PAGE_SIZE); > + kbuf = kmalloc(count, GFP_KERNEL); > + if (!kbuf) > + return -ENOMEM; > + > + if (copy_from_user(kbuf, buf, count)) { > + ret = -EFAULT; > + goto out; > + } > + > + kbuf[count - 1] = '\0'; > + > + ret = kstrtoul(kbuf, 10, &threshold); > + > +out: > + kfree(kbuf); > + return ret ? ret : count; > +} Still the same comment on this, kmalloc() is not really needed here. Capping the size to PAGE_SIZE (usually 4K) is too big. `unsinged long` is 64-bit at most, this means the max val is 18446744073709551615 (20 chars). The lifetime of @kbuf is very short as well, using a stack allocated array of chars is fine? Untested: static ssize_t write_page_owner_threshold(struct file *file, const char __user *buf, size_t count, loff_t *pos) { char kbuf[21]; int ret; count = min_t(size_t, count, sizeof(kbuf)); if (copy_from_user(kbuf, buf, count)) return -EFAULT; kbuf[count - 1] = '\0'; ret = kstrtoul(kbuf, 10, &threshold); return ret ? ret : count; } -- Ammar Faizi