From nobody Mon Apr 08 19:04:45 2024 X-Original-To: dev-commits-src-all@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4VCz6k1n1tz5HYhN; Mon, 8 Apr 2024 19:04:46 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4VCz6j6RXNz4h83; Mon, 8 Apr 2024 19:04:45 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1712603085; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=ftzzHVo0p2B6ZtianVXIk3VewyefpDKvXsH4bjaqzKc=; b=p0h6tM8CyipF/i9qJ2nb0hFBo/dFMhvzZCX/n7OjVhWTwmYSAxH/7Kg7PP6SzA2G+BydEE yLRbb5t0R1TlHZgtQmzpTJEZjD4mk83dg6zPKKGvK7XTPH2UpAJLyWa7OncKnLzAxYozL5 QxUKQ4xqnULjz6euUMVL01kXuBhvxJiQe3CdM7leMz86PeWiE4iZQI7YzlWlDy1MGJM+ZX 5Vz6EaBvbZ/LlWepBUGBJD34cz0RYlGwDZVxmSFzFd18mkacPE5euBTnYtp63xUeDYIP+U AsvzsQVVcnSQLBEqVRKqUVVbGpX+PkZK68rYG8pMKMLXzhxKvIhq6YoNNrS0Cw== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1712603085; a=rsa-sha256; cv=none; b=fEP+ptL2cm3T9vp65D3o2GhKhC1Um73Ya08D86JPIkamnfz7qXfBj1mx8o4Gfyy5q8eTpX RsNxvokI4L+vs4etSn7sralXJ9iYHv6vIPtsliUp4Ei6moH2oPYpHzNXCt36kpbyk2L6sa mLOiwsk3E2PvFTUky5+dwwNOE9jaixjbSA7KVv74kO/qKKi0DVj6GTnRZci26ns8dfvLai m4KV5lno3d2n/otODn9p9wpupDZjM47JdM5ilje9H6KPNwumSW9q0kslXerSxNwBIBNN7c vsyD0v/giPODjg/wCjxB5YN3jPiKEeMrFaBRYV9F7mNQhI5+D9BP3VxCNBYeMA== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1712603085; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=ftzzHVo0p2B6ZtianVXIk3VewyefpDKvXsH4bjaqzKc=; b=F6eoT33fXYLrjzodbhH9C26ROzHagUqEqtQReMCq13sh7jG1PN+ugN4K+gaizUj48q3uOd up0jFPw47qhfaX7qOZ/H3hEUiZPjwShNa+aQX8Oggv5KkVv1ZXdmLdFAaLoEjM6BTXZuSP dYEASQA3Yk4MccMZxpuVfIu4z2XhN7NG2OezDD00cmJwMBDz/MTLjUWsa2erQtH7r3bI8r /vdTY7IpTtMlbjywOP0Ruhf26LNPX/z9Q1nBpHmQl0f1wKUxHcWBGkvRXI0llzFk0FnVrM d/CM8wa/NCcD6HJn96YK010z+W9D5v1ezPVNGw31955tF/NaLwfQUw1DjcX/cQ== Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 4VCz6j5zWQzN1K; Mon, 8 Apr 2024 19:04:45 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.17.1/8.17.1) with ESMTP id 438J4jSe095053; Mon, 8 Apr 2024 19:04:45 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.17.1/8.17.1/Submit) id 438J4jUR095050; Mon, 8 Apr 2024 19:04:45 GMT (envelope-from git) Date: Mon, 8 Apr 2024 19:04:45 GMT Message-Id: <202404081904.438J4jUR095050@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org From: John Baldwin Subject: git: 30eab966575f - stable/14 - kldxref: Properly handle reading strings near the end of an ELF file List-Id: Commit messages for all branches of the src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-all List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-dev-commits-src-all@freebsd.org X-BeenThere: dev-commits-src-all@freebsd.org MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: jhb X-Git-Repository: src X-Git-Refname: refs/heads/stable/14 X-Git-Reftype: branch X-Git-Commit: 30eab966575fccbb85d54902667530b6a6e66e45 Auto-Submitted: auto-generated The branch stable/14 has been updated by jhb: URL: https://cgit.FreeBSD.org/src/commit/?id=30eab966575fccbb85d54902667530b6a6e66e45 commit 30eab966575fccbb85d54902667530b6a6e66e45 Author: John Baldwin AuthorDate: 2024-03-19 00:01:23 +0000 Commit: John Baldwin CommitDate: 2024-04-08 18:06:13 +0000 kldxref: Properly handle reading strings near the end of an ELF file If a string is at or near the end of an input file and the amount of remaining data in the file is smaller than the maximum string size, the pread(2) system call would return a short read which is treated as an error. Instead, add a new helper function for reading a string which permits short reads so long as the data read from the file contains a terminated string. Reported by: jrtc27 Reviewed by: jrtc27 Sponsored by: University of Cambridge, Google, Inc. Differential Revision: https://reviews.freebsd.org/D44419 (cherry picked from commit 785600d0fb13d6f0b4595bf4dbbc048113dda71d) --- usr.sbin/kldxref/ef.c | 9 +-------- usr.sbin/kldxref/ef.h | 4 ++++ usr.sbin/kldxref/ef_obj.c | 9 +-------- usr.sbin/kldxref/elf.c | 18 ++++++++++++++++++ 4 files changed, 24 insertions(+), 16 deletions(-) diff --git a/usr.sbin/kldxref/ef.c b/usr.sbin/kldxref/ef.c index 1ef27f2bc54a..77ddada946f2 100644 --- a/usr.sbin/kldxref/ef.c +++ b/usr.sbin/kldxref/ef.c @@ -549,7 +549,6 @@ static int ef_seg_read_string(elf_file_t ef, GElf_Addr address, size_t len, char *dest) { GElf_Off ofs; - int error; ofs = ef_get_offset(ef, address); if (ofs == 0) { @@ -559,13 +558,7 @@ ef_seg_read_string(elf_file_t ef, GElf_Addr address, size_t len, char *dest) return (EFAULT); } - error = elf_read_raw_data(ef->ef_efile, ofs, dest, len); - if (error != 0) - return (error); - if (strnlen(dest, len) == len) - return (EFAULT); - - return (0); + return (elf_read_raw_string(ef->ef_efile, ofs, dest, len)); } int diff --git a/usr.sbin/kldxref/ef.h b/usr.sbin/kldxref/ef.h index 25dc5216b169..9d3dc1b1b435 100644 --- a/usr.sbin/kldxref/ef.h +++ b/usr.sbin/kldxref/ef.h @@ -189,6 +189,10 @@ int elf_read_raw_data(struct elf_file *efile, off_t offset, void *dst, int elf_read_raw_data_alloc(struct elf_file *efile, off_t offset, size_t len, void **out); +/* Reads a single string at the given offset from an ELF file. */ +int elf_read_raw_string(struct elf_file *efile, off_t offset, char *dst, + size_t len); + /* * Read relocated data from an ELF file and return it in a * dynamically-allocated buffer. Note that no translation diff --git a/usr.sbin/kldxref/ef_obj.c b/usr.sbin/kldxref/ef_obj.c index 1274a14c10af..ac83137cd394 100644 --- a/usr.sbin/kldxref/ef_obj.c +++ b/usr.sbin/kldxref/ef_obj.c @@ -248,7 +248,6 @@ static int ef_obj_seg_read_string(elf_file_t ef, GElf_Addr address, size_t len, char *dest) { GElf_Off ofs; - int error; ofs = ef_obj_get_offset(ef, address); if (ofs == 0) { @@ -258,13 +257,7 @@ ef_obj_seg_read_string(elf_file_t ef, GElf_Addr address, size_t len, char *dest) return (EFAULT); } - error = elf_read_raw_data(ef->ef_efile, ofs, dest, len); - if (error != 0) - return (error); - if (strnlen(dest, len) == len) - return (EFAULT); - - return (0); + return (elf_read_raw_string(ef->ef_efile, ofs, dest, len)); } int diff --git a/usr.sbin/kldxref/elf.c b/usr.sbin/kldxref/elf.c index e5fe90169d2c..a93cf996ccc7 100644 --- a/usr.sbin/kldxref/elf.c +++ b/usr.sbin/kldxref/elf.c @@ -197,6 +197,24 @@ elf_read_raw_data_alloc(struct elf_file *efile, off_t offset, size_t len, return (0); } +int +elf_read_raw_string(struct elf_file *efile, off_t offset, char *dst, size_t len) +{ + ssize_t nread; + + nread = pread(efile->ef_fd, dst, len, offset); + if (nread == -1) + return (errno); + if (nread == 0) + return (EIO); + + /* A short read is ok so long as the data contains a terminator. */ + if (strnlen(dst, nread) == nread) + return (EFAULT); + + return (0); +} + int elf_read_data(struct elf_file *efile, Elf_Type type, off_t offset, size_t len, void **out)