From patchwork Thu Aug 29 17:42:29 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrii Nakryiko X-Patchwork-Id: 13783502 X-Patchwork-Delegate: bpf@iogearbox.net Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DA73F1B78E0; Thu, 29 Aug 2024 17:42:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724953377; cv=none; b=Ubv2iyjmfwXRkRyjjDHmx80paorM033SLU/alvcUwN6GDT/ir5TkQsJ7X3SBwjnKJHWTbEmAk6iy0G70BU5ySXzLqhTpqvl6jbl13Lhs6qj7JY7pLs+jrlsjHYbyxLnoys0tVB1N0XX1GoBDZbqVzEdlkrzRv2OmCrAlbF6Jj5Q= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724953377; c=relaxed/simple; bh=2jVZvSaSmUP1eILbkNsVbAsPQzYYbYwqDjRGc+xq+N4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=j9CsCSYNMMNgF1TCowhm25IWUrMpaQY13ROX8Wivd/E0pqZWnClGxYr2mlcQj9lhy27iDTNfE4qAJAkq6HPDzR/EXC2+m4RlZ7SE0oAtySxVznCyXzqRydOZeMkFsIH9m2LhAMNE2HWXVjjspKQGC0CwF+nkQrwnaCNyGTxX9pI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Iij0aW8j; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Iij0aW8j" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8E162C4CEC1; Thu, 29 Aug 2024 17:42:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1724953377; bh=2jVZvSaSmUP1eILbkNsVbAsPQzYYbYwqDjRGc+xq+N4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Iij0aW8jjwJqgQiw3EdbzhJ/zMX2hOtDDDPvqLD6dR//5hE2vlBaFNc1Zns9oO8Of fbYp4hyEnZlujg6/CwOVGXypguIDPW8QB1Q8pOqX55ZuVvyzbejBkFqvg4eB//Bwkw Ql2O4bvlqmgE5bDgmeHYob++eJop6Sq5bENwENUgVel5WIDH2dogQ19O97M+HxhjZa 4lR64OjtEtn+0wJOpHHvZdIHAa24eN8rv8AVfdm0rqsm5ow3yZGLedfPASdB+8xa3X 02bHyiJawK+xM63XbjtQExRwHZOnHvqLT6SRaeE63Rl0/R7SRQXbCPWVUbF1nsrfu6 RLwIVPacoRcsg== From: Andrii Nakryiko To: bpf@vger.kernel.org Cc: linux-mm@kvack.org, akpm@linux-foundation.org, adobriyan@gmail.com, shakeel.butt@linux.dev, hannes@cmpxchg.org, ak@linux.intel.com, osandov@osandov.com, song@kernel.org, jannh@google.com, linux-fsdevel@vger.kernel.org, willy@infradead.org, Andrii Nakryiko , Eduard Zingerman Subject: [PATCH v7 bpf-next 07/10] lib/buildid: don't limit .note.gnu.build-id to the first page in ELF Date: Thu, 29 Aug 2024 10:42:29 -0700 Message-ID: <20240829174232.3133883-8-andrii@kernel.org> X-Mailer: git-send-email 2.43.5 In-Reply-To: <20240829174232.3133883-1-andrii@kernel.org> References: <20240829174232.3133883-1-andrii@kernel.org> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: bpf@iogearbox.net With freader we don't need to restrict ourselves to a single page, so let's allow ELF notes to be at any valid position with the file. We also merge parse_build_id() and parse_build_id_buf() as now the only difference between them is note offset overflow, which makes sense to check in all situations. Reviewed-by: Eduard Zingerman Signed-off-by: Andrii Nakryiko --- lib/buildid.c | 26 +++++--------------------- 1 file changed, 5 insertions(+), 21 deletions(-) diff --git a/lib/buildid.c b/lib/buildid.c index 18ef55812c64..290641d92ac1 100644 --- a/lib/buildid.c +++ b/lib/buildid.c @@ -155,9 +155,8 @@ static void freader_cleanup(struct freader *r) * 32-bit and 64-bit system, because Elf32_Nhdr and Elf64_Nhdr are * identical. */ -static int parse_build_id_buf(struct freader *r, - unsigned char *build_id, __u32 *size, - loff_t note_off, Elf32_Word note_size) +static int parse_build_id(struct freader *r, unsigned char *build_id, __u32 *size, + loff_t note_off, Elf32_Word note_size) { const char note_name[] = "GNU"; const size_t note_name_sz = sizeof(note_name); @@ -165,7 +164,9 @@ static int parse_build_id_buf(struct freader *r, const Elf32_Nhdr *nhdr; const char *data; - note_end = note_off + note_size; + if (check_add_overflow(note_off, note_size, ¬e_end)) + return -EINVAL; + while (note_end - note_off > sizeof(Elf32_Nhdr) + note_name_sz) { nhdr = freader_fetch(r, note_off, sizeof(Elf32_Nhdr) + note_name_sz); if (!nhdr) @@ -204,23 +205,6 @@ static int parse_build_id_buf(struct freader *r, return -EINVAL; } -static inline int parse_build_id(struct freader *r, - unsigned char *build_id, - __u32 *size, - loff_t note_start_off, - Elf32_Word note_size) -{ - /* check for overflow */ - if (note_start_off + note_size < note_start_off) - return -EINVAL; - - /* only supports note that fits in the first page */ - if (note_start_off + note_size > PAGE_SIZE) - return -EINVAL; - - return parse_build_id_buf(r, build_id, size, note_start_off, note_size); -} - /* Parse build ID from 32-bit ELF */ static int get_build_id_32(struct freader *r, unsigned char *build_id, __u32 *size) {