From mboxrd@z Thu Jan 1 00:00:00 1970 Delivery-date: Thu, 01 Aug 2024 08:03:45 +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 1sZOuf-0052Iq-0I for lore@lore.pengutronix.de; Thu, 01 Aug 2024 08:03:45 +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 1sZOud-0001kd-HA for lore@pengutronix.de; Thu, 01 Aug 2024 08:03:44 +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=C5qSbpbplXAt+Ftti8/VfmAvt7lkXuhFH/wy+V2J7f0=; b=jTemJGl3YsSq6Yd82/26Psxj+r 860QHC5VzA7IxUNCwWy+AGImT52zIJDejPXinsxlLANPTghUR47CFcP+UMAMlvFBUpjE2y/034Ixo gxmlITElGymN8d6WJK6epNvZEC47Q4NMeZBbI9WOgVxpMEAinDSAIbx3WGj54NSjiAPhpRxtJz47M x86G4nQ4ZT28nZRbRC4mG2c3EdyfCToog0TTTR5LkPDZp2VWFyyjMvVhLylRqzgamtwreB3a9dj0+ +llbJ8qk/Qezrnhyk7cn+67uwu4FyTW2N6zwvmrwq0L1VTssCEiVuqbDeg2u/jeblC3yP41Msujbs PaEBDU2w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sZOu6-00000003qU1-19mQ; Thu, 01 Aug 2024 06:03:10 +0000 Received: from metis.whiteo.stw.pengutronix.de ([2a0a:edc0:2:b01:1d::104]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sZOu1-00000003qQH-00G8 for barebox@lists.infradead.org; Thu, 01 Aug 2024 06:03:06 +0000 Received: from drehscheibe.grey.stw.pengutronix.de ([2a0a:edc0:0:c01:1d::a2]) by metis.whiteo.stw.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1sZOtz-0001IO-SS; Thu, 01 Aug 2024 08:03:03 +0200 Received: from [2a0a:edc0:0:1101:1d::28] (helo=dude02.red.stw.pengutronix.de) by drehscheibe.grey.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1sZOtz-003hX5-Fe; Thu, 01 Aug 2024 08:03:03 +0200 Received: from localhost ([::1] helo=dude02.red.stw.pengutronix.de) by dude02.red.stw.pengutronix.de with esmtp (Exim 4.96) (envelope-from ) id 1sZOol-00DNum-0V; Thu, 01 Aug 2024 07:57:39 +0200 From: Sascha Hauer To: Barebox List Date: Thu, 1 Aug 2024 07:57:33 +0200 Message-Id: <20240801055737.3190132-16-s.hauer@pengutronix.de> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240801055737.3190132-1-s.hauer@pengutronix.de> References: <20240801055737.3190132-1-s.hauer@pengutronix.de> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240731_230305_057564_E05E62D4 X-CRM114-Status: GOOD ( 12.17 ) 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=-5.3 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 v2 15/19] malloc: implement free_sensitive() 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) barebox sometimes stores sensitive data in memory. Add a (k)free_sensitive() function which zeroes out the memory before freeing it. Signed-off-by: Sascha Hauer --- common/dlmalloc.c | 15 +++++++++++++++ common/tlsf_malloc.c | 11 +++++++++++ include/dma.h | 5 +++++ include/linux/slab.h | 5 +++++ include/malloc.h | 1 + 5 files changed, 37 insertions(+) diff --git a/common/dlmalloc.c b/common/dlmalloc.c index c41487d54b..0e23399b2b 100644 --- a/common/dlmalloc.c +++ b/common/dlmalloc.c @@ -1431,6 +1431,21 @@ void free(void *mem) frontlink(p, sz, idx, bck, fwd); } +void free_sensitive(void *mem) +{ + mchunkptr p; + size_t size; + + if (!mem) + return; + + p = mem2chunk(mem); + size = chunksize(p); + if (size) + memset(mem, size, 0x0); + + free(mem); +} /* Realloc algorithm: diff --git a/common/tlsf_malloc.c b/common/tlsf_malloc.c index 981f09de41..5bcbbcd2f8 100644 --- a/common/tlsf_malloc.c +++ b/common/tlsf_malloc.c @@ -38,6 +38,17 @@ void free(void *mem) } EXPORT_SYMBOL(free); +void free_sensitive(void *mem) +{ + size_t size; + + size = tlsf_block_size(mem); + if (size) + memset(mem, size, 0x0); + + tlsf_free(tlsf_mem_pool, mem); +} + void *realloc(void *oldmem, size_t bytes) { void *mem = tlsf_realloc(tlsf_mem_pool, oldmem, bytes); diff --git a/include/dma.h b/include/dma.h index 4fcd114bb6..c2b1bee358 100644 --- a/include/dma.h +++ b/include/dma.h @@ -41,6 +41,11 @@ static inline void dma_free(void *mem) free(mem); } +static inline void dma_free_sensitive(void *mem) +{ + free_sensitive(mem); +} + #define DMA_BIT_MASK(n) (((n) == 64) ? ~0ULL : ((1ULL<<(n))-1)) #define DMA_MASK_NONE 0x0ULL diff --git a/include/linux/slab.h b/include/linux/slab.h index eba3593d75..8c82e19866 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -67,6 +67,11 @@ static inline void kfree(const void *mem) dma_free((void *)mem); } +static inline void kfree_sensitive(const void *objp) +{ + dma_free_sensitive((void *)objp); +} + static inline void *kmem_cache_alloc(struct kmem_cache *cache, gfp_t flags) { void *mem = kmalloc(cache->size, flags); diff --git a/include/malloc.h b/include/malloc.h index d63853b91e..c25bbf6949 100644 --- a/include/malloc.h +++ b/include/malloc.h @@ -7,6 +7,7 @@ void *malloc(size_t) __alloc_size(1); void free(void *); +void free_sensitive(void *); void *realloc(void *, size_t) __realloc_size(2); void *memalign(size_t, size_t) __alloc_size(2); void *calloc(size_t, size_t) __alloc_size(1, 2); -- 2.39.2