From mboxrd@z Thu Jan 1 00:00:00 1970 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 1806B13D610 for ; Wed, 24 Jul 2024 22:52:33 +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=1721861554; cv=none; b=CpuQlriia7VLcH0hVhVYrJSMG74wrG/mOK3vskwmnJEvGslYwwoGUayLQqG0Nj92yoj0F7qQyQzopoPRSZAYRYdYx4UfJaf8JGd9tlHetFQPhdSqNRtt2UPGtd6uCtRaNo+bkIAByjTN7LdWlqtn0OkcXo66tdz7T6H2lX3vO38= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721861554; c=relaxed/simple; bh=z2GiV9WjwgN2ZnoTOoBHdWopafhvx9MuPC6sEC6Crd8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=LOhTIsSps+mNV0HU/IPdRv6hMC/vDrXMbXWPKqLKXetpDaDTA7I/aB86GchZQ8C4dR0QxOlflxj1RFFExzL1WkWkVbyRXlCP/K0ovfQgMGfskLHXR/y/cd19NJ5o54nCdS3HbjbDhm4w7S83rB8OCgQb+6cEu8nuXWpmqZGV2+w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=iHUH9AVU; 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="iHUH9AVU" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 788D3C32781; Wed, 24 Jul 2024 22:52:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1721861553; bh=z2GiV9WjwgN2ZnoTOoBHdWopafhvx9MuPC6sEC6Crd8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iHUH9AVUcEK7NLYHGspPRaMdC8HeusUjt3LTsHRjp9gWWo4MPW4MgLl2MGu3YDiIs xVyIwtqGyMCbLdQyVaoad66Nd0AA9SZ+DyPte034LGtLR7fMFcHhOKt8yV5Pi1zHCV 7NIF+N1Jgy1otd8xqT8YO1nsRgn33w2pwuxtxCiWzVy/AyvV5kCs5GbNH9l7iEojsQ 0mBTpOZrMJlWbOXIk690QI2WW2TOrsWw9b4/lRTZgE4+q/bMAR3EsUPnO8vFWkD80U 3kWPgDLeUtEvxJnjxMcMrqxANgHr5nvlHIwutDewpDBIRh5kCeXTbwsPo0/iF5oCME rrEf7fiznF4RQ== 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, Andrii Nakryiko Subject: [PATCH v2 bpf-next 06/10] lib/buildid: don't limit .note.gnu.build-id to the first page in ELF Date: Wed, 24 Jul 2024 15:52:06 -0700 Message-ID: <20240724225210.545423-7-andrii@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240724225210.545423-1-andrii@kernel.org> References: <20240724225210.545423-1-andrii@kernel.org> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 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. Signed-off-by: Andrii Nakryiko --- lib/buildid.c | 28 +++++++--------------------- 1 file changed, 7 insertions(+), 21 deletions(-) diff --git a/lib/buildid.c b/lib/buildid.c index 23bfc811981a..419966d88cd5 100644 --- a/lib/buildid.c +++ b/lib/buildid.c @@ -152,9 +152,8 @@ 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, - u64 note_offs, Elf32_Word note_size) +static int parse_build_id(struct freader *r, unsigned char *build_id, __u32 *size, + u64 note_offs, Elf32_Word note_size) { const char note_name[] = "GNU"; const size_t note_name_sz = sizeof(note_name); @@ -163,6 +162,10 @@ static int parse_build_id_buf(struct freader *r, const Elf32_Nhdr *nhdr; const char *data; + /* check for overflow */ + if (note_offs + note_size < note_offs) + return -EINVAL; + while (note_offs + sizeof(Elf32_Nhdr) < note_end) { nhdr = freader_fetch(r, note_offs, sizeof(Elf32_Nhdr) + note_name_sz); if (!nhdr) @@ -199,23 +202,6 @@ 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, - u64 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) { @@ -369,7 +355,7 @@ int build_id_parse_buf(const void *buf, unsigned char *build_id, u32 buf_size) freader_init_from_mem(&r, buf, buf_size); - return parse_build_id_buf(&r, build_id, NULL, 0, buf_size); + return parse_build_id(&r, build_id, NULL, 0, buf_size); } #if IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID) || IS_ENABLED(CONFIG_VMCORE_INFO) -- 2.43.0