From mboxrd@z Thu Jan 1 00:00:00 1970 Delivery-date: Tue, 27 May 2025 23:31:59 +0200 Received: from metis.whiteo.stw.pengutronix.de ([2a0a:edc0:2:b01:1d::104]) by lore.white.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1uK1tv-000yNq-0S for lore@lore.pengutronix.de; Tue, 27 May 2025 23:31:59 +0200 Received: from bombadil.infradead.org ([2607:7c80:54:3::133]) by metis.whiteo.stw.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1uK1ts-0005nU-Dz for lore@pengutronix.de; Tue, 27 May 2025 23:31:58 +0200 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To: Cc:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=zjBRmaqHoKTGbacN3K89noPFDl1wFrHh8G5Q74vcC4Y=; b=hXXJ6SXQWI/qfFCObSF5Sq7I/b bDMxzo6MFEYXBDMT7ABK1t3jvhiamW8J0+rMBZZ+Ce7ePJnmkhr6nYuqGIzKYXb+EeA1XifFcwZpJ GOM2RvQoMAg8IuuZcgz1NGc6HR8CCnWqJpWPu30umrAbwkRFZGHsRzc6cZ+lqJyR8gfnFCGyKeqHs iJdvVr/Zqu4oAhLJMW4aKUHB0/m+u4imLikT8vaKKVihy/QACOMcONVlP8b+JdboRnVm6x3MjYGjD 3iVGR4FQ9bL9sAscNalgEce5wU3X9M/dfL6s+nTh0lKvnMGePs6X5ZfpqNmQBnMlPQOtcCT5SwpwX jhASex+w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uK1tH-0000000BbkK-2TJi; Tue, 27 May 2025 21:31:19 +0000 Received: from metis.whiteo.stw.pengutronix.de ([2a0a:edc0:2:b01:1d::104]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1uK1lN-0000000BaxA-0c49 for barebox@lists.infradead.org; Tue, 27 May 2025 21:23:10 +0000 Received: from ptz.office.stw.pengutronix.de ([2a0a:edc0:0:900:1d::77] helo=geraet.fritz.box) by metis.whiteo.stw.pengutronix.de with esmtp (Exim 4.92) (envelope-from ) id 1uK1lL-00015n-Lc for barebox@lists.infradead.org; Tue, 27 May 2025 23:23:08 +0200 From: Ahmad Fatoum To: barebox@lists.infradead.org Date: Tue, 27 May 2025 23:22:51 +0200 Message-Id: <20250527212300.575031-7-a.fatoum@barebox.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250527212300.575031-1-a.fatoum@barebox.org> References: <20250527212300.575031-1-a.fatoum@barebox.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250527_142309_190743_C31B66FA X-CRM114-Status: GOOD ( 10.69 ) X-BeenThere: barebox@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "barebox" X-SA-Exim-Connect-IP: 2607:7c80:54:3::133 X-SA-Exim-Mail-From: barebox-bounces+lore=pengutronix.de@lists.infradead.org X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on metis.whiteo.stw.pengutronix.de X-Spam-Level: X-Spam-Status: No, score=-7.6 required=4.0 tests=AWL,BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED,SPF_HELO_NONE,SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.2 Subject: [PATCH 06/15] string: implement kmemdup_nul X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on metis.whiteo.stw.pengutronix.de) From: Ahmad Fatoum Unlike memdup and strdup, memdup_nul ensures that the output is NUL terminated, while not expecting the input to be so. Signed-off-by: Ahmad Fatoum --- include/linux/string.h | 6 ++++++ lib/string.c | 42 ++++++++++++++++++++++++++---------------- 2 files changed, 32 insertions(+), 16 deletions(-) diff --git a/include/linux/string.h b/include/linux/string.h index 0fa84f095e02..953484ebc9f6 100644 --- a/include/linux/string.h +++ b/include/linux/string.h @@ -175,6 +175,12 @@ static inline void *memdup(const void *buf, size_t size) } #endif +extern char *memdup_nul(const char *s, size_t len); +static inline char *kmemdup_nul(const char *s, size_t len, gfp_t gfp) +{ + return memdup_nul(s, len); +} + #define memdup_array(arr, count) memdup(arr, array_size(count, sizeof(*arr))); static inline void *kmemdup(const void *src, size_t len, gfp_t gfp) diff --git a/lib/string.c b/lib/string.c index f2272be37e76..33d61add8189 100644 --- a/lib/string.c +++ b/lib/string.c @@ -423,42 +423,52 @@ size_t strnlen(const char * s, size_t count) #endif EXPORT_SYMBOL(strnlen); -#ifndef __HAVE_ARCH_STRDUP -char * strdup(const char *s) +static __always_inline char *__memdup_nul(const char *s, size_t len) { char *new; if ((s == NULL) || - ((new = malloc (strlen(s) + 1)) == NULL) ) { + ((new = malloc (len + 1)) == NULL) ) { return NULL; } - strcpy (new, s); + memcpy (new, s, len); + /* Ensure the buf is always NUL-terminated, regardless of @s. */ + new[len] = '\0'; return new; } + +#ifndef __HAVE_ARCH_STRDUP +char * strdup(const char *s) +{ + return s ? __memdup_nul(s, strlen(s)) : NULL; +} #endif EXPORT_SYMBOL(strdup); #ifndef __HAVE_ARCH_STRNDUP char *strndup(const char *s, size_t n) { - char *new; - size_t len = strnlen(s, n); - - if ((s == NULL) || - ((new = malloc(len + 1)) == NULL)) { - return NULL; - } - - memcpy(new, s, len); - new[len] = '\0'; - - return new; + return s ? __memdup_nul(s, strnlen(s, n)) : NULL; } #endif EXPORT_SYMBOL(strndup); +/** + * memdup_nul - Create a NUL-terminated string from @s, which might be unterminated. + * @s: The data to copy + * @len: The size of the data, not including the NUL terminator + * + * Return: newly allocated copy of @s with NUL-termination or %NULL in + * case of error + */ +char *memdup_nul(const char *s, size_t n) +{ + return s ? __memdup_nul(s, n) : NULL; +} +EXPORT_SYMBOL(memdup_nul); + #ifndef __HAVE_ARCH_STRSPN /** * strspn - Calculate the length of the initial substring of @s which only -- 2.39.5