From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793213201; b=vNdTWXCgxuwRjQ3I8c2qKcUkRu1ow1WC4F8//x38V9WKzUfVnW1gI05XjZx3g7hnpHq5 arbTfiwbSh7ZiSjQel9jS9LuaZHAuMbVst9zvaQ3cbDh/f4i3HTaEGWCoxT9T7nU97uQV qsMJL5GtTjFjYEpABf3mX1pk9eU0jhSGoSvT2sGPXGH+/SNQP/ueE94hVaI9AMNumCjq6 RwpLmQ9uJcoP/t53s89A4bqOljLPpdAuYLkU9evcOEJpGHdWWCO8bddHC3IsM0teTK+PK SMxnmGiXBLoyknFoyT1MrHMONHlBfRCQuMVKRFTsc1qBkeb2pdiRvKgliTRhTPfEX5g== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793213201; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Type:Content-Transfer-Encoding; bh=weV/xo9+4dGyh9XJRzZJs1v7YHTXiQ1rHEaVvX2aCwU=; b=XlBIXpmGK4hPGUngukp8ld9VgMpTlzJOmFX6R4Hyq/OZNjAywFEMqwxSpnPf8Lq8VtdI J5vGUbBhPXf09MQlOm7ExOuKD7UgeFD6L1BorDrfAIDSIc+qBuvI003ryhetaMSgkompA yg0TzY/TqojndYy09GwXgyM7ZyBCm3s2HUkQWVAPn6Ao6j0AhPsE165TvyYWvZgqUhkV0 KnGvjbEglpJgDC6VLTNgQDjegCL44RP0wxPG5L8pg1JIz/k1Ck+uE5t2SCsbE8ijUcaTj Rns0LRqn6CtNRA9qST1VF7T78fqlbZssPF6zJ27LeWyNob/1xS1+IL59BixJ4wQlAvg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=NY8tyI9j; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B7E8F606A31D; Wed, 28 Oct 2026 18:46:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=NY8tyI9j Received: by smtp.kernel.org (Postfix) with ESMTPSA id 06C801F01825; Wed, 28 Oct 2026 18:46:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793213200; bh=weV/xo9+4dGyh9XJRzZJs1v7YHTXiQ1rHEaVvX2aCwU=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=NY8tyI9jHAvhJYwCVke2v/DUjcTK5M3y9EFvz+R7V2fy0BAqn3DLKSzZ6UgThYiBO 1r/98FjpGkerNAwNCFmTBO3Js24sgjUxFnBTMqBcY+4OPLw8DJJnIcrSJf/VhtPEcA O5xHjmb26hF9+cCmLE1HOn4THMWEgMta4I3X0FsY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, =?UTF-8?q?HE=20WEI=EF=BC=88=E3=82=AE=E3=82=AB=E3=82=AF=EF=BC=89?= , Konstantin Komarov , Nikita Nagornyi , Sasha Levin Subject: [PATCH 6.1 0421/1887] fs/ntfs3: fix slab-out-of-bounds write in ni_create_attr_list() Date: Wed, 28 Oct 2026 17:41:57 +0100 Message-ID: <20261028170508.814668589@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261028170459.200466217@linuxfoundation.org> References: <20261028170459.200466217@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: HE WEI（ギカク） [ Upstream commit 7c4841e2a62794a3bab7c1ff0540580f387e377f ] ni_create_attr_list() allocates a fixed buffer of al_aligned(record_size) (== record_size) bytes and then walks every attribute of the primary MFT record, writing one ATTR_LIST_ENTRY per attribute and advancing the cursor by le_size(name_len), with no check against the end of the buffer; the total size is only computed after the loop. A minimum-size resident attribute occupies SIZEOF_RESIDENT (0x18 = 24) bytes on disk, but an unnamed attribute expands to le_size(0) (0x20 = 32) bytes in the list. Because the number of attributes in a record is not bounded (mi_enum_attr() accepts arbitrarily many equal-type, nameless minimum-size attributes), a crafted record packed with such attributes produces a list larger than record_size and overflows the heap buffer. This is reachable from a crafted, loop-mounted NTFS image: opening the file and adding an attribute (e.g. via setxattr) drives ntfs_set_ea() -> ni_insert_resident() -> ni_insert_attr() -> ni_ins_attr_ext() -> ni_create_attr_list(). BUG: KASAN: slab-out-of-bounds in ni_create_attr_list+0xc48/0x1058 Write of size 4 at addr ffff000008984c00 by task setfattr/345 ni_create_attr_list+0xc48/0x1058 ni_ins_attr_ext+0x510/0x7c0 ni_insert_attr+0x3f8/0x70c ni_insert_resident+0xc8/0x3b0 ntfs_set_ea+0x66c/0xd28 ntfs_setxattr+0x4d8/0x5b0 __arm64_sys_setxattr+0xa4/0x124 Allocated by task 345: ni_create_attr_list+0x188/0x1058 The buggy address belongs to the cache kmalloc-1k of size 1024 (the write lands at object+1024). Size the buffer from the actual attributes instead of assuming a single record_size is always enough. Fixes: 4342306f0f0d ("fs/ntfs3: Add file operations and implementation") Reported-by: HE WEI（ギカク） Signed-off-by: HE WEI（ギカク） Signed-off-by: Konstantin Komarov Signed-off-by: Nikita Nagornyi Signed-off-by: Sasha Levin --- fs/ntfs3/frecord.c | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-) diff --git a/fs/ntfs3/frecord.c b/fs/ntfs3/frecord.c index c9d0947651c4e..240983bac9c3c 100644 --- a/fs/ntfs3/frecord.c +++ b/fs/ntfs3/frecord.c @@ -816,10 +816,23 @@ int ni_create_attr_list(struct ntfs_inode *ni) rs = sbi->record_size; /* - * Skip estimating exact memory requirement. - * Looks like one record_size is always enough. + * Compute the exact size of the attribute list. Each attribute in the + * record yields one ATTR_LIST_ENTRY of le_size(name_len) bytes. The + * minimum on-disk attribute is SIZEOF_RESIDENT (0x18) bytes, but an + * unnamed one expands to le_size(0) (0x20) here, so a record crafted + * with many such attributes needs more than a single record_size; the + * previous fixed kzalloc(record_size) could therefore be overflowed by + * an attacker-controlled record. */ - le = kzalloc(al_aligned(rs), GFP_NOFS); + lsize = 0; + attr = NULL; + while ((attr = mi_enum_attr(ni, &ni->mi, attr))) + lsize += le_size(attr->name_len); + + if (!lsize) + return -EINVAL; + + le = kzalloc(al_aligned(lsize), GFP_NOFS); if (!le) { err = -ENOMEM; goto out; @@ -831,7 +844,6 @@ int ni_create_attr_list(struct ntfs_inode *ni) attr = NULL; nb = 0; free_b = 0; - attr = NULL; for (; (attr = mi_enum_attr(ni, &ni->mi, attr)); le = Add2Ptr(le, sz)) { sz = le_size(attr->name_len); -- 2.53.0