From nobody Sat Sep 26 16:40:09 2026 Received: from out30-101.freemail.mail.aliyun.com (out30-101.freemail.mail.aliyun.com [115.124.30.101]) (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 66F6E14A4CC for ; Tue, 1 Sep 2026 12:52:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.101 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788267151; cv=none; b=U3SkXBHfe+p+v7KXYj+4DQLPvc1OxVi6Q7rdHc983tifdcynoQXxH1ZaACmBWB8utwiwoIQtyjcMI5L/jRpFQqTrL9Fmf7gq3x1911kfOcvGKNMTTjMTp/48OinBdZbUTsOClqkRXLIJVDnkK/rsHH1Z66sAv80xaMN3a3tHf0Q= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788267151; c=relaxed/simple; bh=5R3l83+AnsGOP1omiDNJHnYYx4quuehlLcZf3o7Rddc=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=TOSyGKKTAhia5iDD2iGhH+vTvGV6BMZqoDF8ODaDdvifq5wTIDT90ZANrXP+CfHMQpjXPU/5oQkWIwUprz6IcREvp1z8lW61k3i94sombHjF5BPac/6VPwC8mVocxgAIZ+ganoX1wePTSdeApdACZixDezLvw1qiwX5kpp+WWmY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b=mJAiKH3T; arc=none smtp.client-ip=115.124.30.101 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b="mJAiKH3T" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1788267143; h=From:To:Subject:Date:Message-Id:MIME-Version; bh=yVWRK7fUCEudtcuozwBanmc7BlPTtipZ34kWdaYysDw=; b=mJAiKH3T60O0uxTJHp2D5foTpe3eMB572RH1adiJ22rKYJ7DkVh03qFg5y4HasVb/KJy1AVIoiPxVXpgycnTaloH8XIJQmnOpK3vr+Wd6mHmq/66rkGr5A9MD3L9SGdS848NM/RJrRiYi+ZnY8ep4VyFgorcZYIDXeCNGjdOyZE= X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R111e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=maildocker-contentspam033037009110;MF=joseph.qi@linux.alibaba.com;NM=1;PH=DS;RN=6;SR=0;TI=SMTPD_---0XA8SdiZ_1788267142; Received: from localhost(mailfrom:joseph.qi@linux.alibaba.com fp:SMTPD_---0XA8SdiZ_1788267142 cluster:ay36) by smtp.aliyun-inc.com; Tue, 01 Sep 2026 20:52:23 +0800 From: Joseph Qi To: Andrew Morton , Heming Zhao Cc: Mark Fasheh , Joel Becker , ocfs2-devel@lists.linux.dev, linux-kernel@vger.kernel.org Subject: [PATCH v3 1/4] ocfs2: restrict OCFS2_INVALID_SLOT suballoc slot to system inodes Date: Tue, 1 Sep 2026 20:52:18 +0800 Message-Id: <20260901125221.1634686-2-joseph.qi@linux.alibaba.com> X-Mailer: git-send-email 2.39.3 In-Reply-To: <20260901125221.1634686-1-joseph.qi@linux.alibaba.com> References: <20260901125221.1634686-1-joseph.qi@linux.alibaba.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" ocfs2_validate_inode_block() currently permits i_suballoc_slot to be OCFS2_INVALID_SLOT for any dinode. Only system inodes created by mkfs.ocfs2 are allocated from the global allocator and thus legitimately carry this value; regular inodes are always allocated from a per-slot suballocator and hence must have a valid slot. If a corrupted regular inode with OCFS2_INVALID_SLOT is accepted, ocfs2_remove_inode() will pass the slot to ocfs2_get_system_file_inode() and get_local_system_inode() will hit BUG_ON(slot =3D=3D OCFS2_INVALID_SLOT) when the inode is deleted. This can be triggered by an unprivileged user unlinking such a corrupted file. Reject OCFS2_INVALID_SLOT for non-system dinodes during validation, while still accepting it for system inodes. Note that a crafted dinode carrying OCFS2_SYSTEM_FL passes the check above, yet a plain lookup of it still used to BUG() in ocfs2_read_locked_inode() ("system file state is ambiguous"). Since i_flags comes from disk, handle that mismatch with ocfs2_error() instead of BUG_ON() as well. Fixes: fe7a283b3916 ("ocfs2: add suballoc slot check in ocfs2_validate_inod= e_block()") Cc: stable@vger.kernel.org Signed-off-by: Joseph Qi --- fs/ocfs2/inode.c | 37 ++++++++++++++++++++++++++++--------- 1 file changed, 28 insertions(+), 9 deletions(-) diff --git a/fs/ocfs2/inode.c b/fs/ocfs2/inode.c index 180107a11046..9228d6ef23c2 100644 --- a/fs/ocfs2/inode.c +++ b/fs/ocfs2/inode.c @@ -638,14 +638,18 @@ static int ocfs2_read_locked_inode(struct inode *inod= e, fe =3D (struct ocfs2_dinode *) bh->b_data; =20 /* - * This is a code bug. Right now the caller needs to - * understand whether it is asking for a system file inode or - * not so the proper lock names can be built. + * The caller must know whether it is asking for a system file inode + * or not so the proper lock names can be built. Since i_flags comes + * from disk, a mismatch is filesystem corruption instead of a code + * bug, so handle it with ocfs2_error() rather than BUG_ON(). */ - mlog_bug_on_msg(!!(fe->i_flags & cpu_to_le32(OCFS2_SYSTEM_FL)) !=3D - !!(args->fi_flags & OCFS2_FI_FLAG_SYSFILE), - "Inode %llu: system file state is ambiguous\n", - (unsigned long long)args->fi_blkno); + if (!!(fe->i_flags & cpu_to_le32(OCFS2_SYSTEM_FL)) !=3D + !!(args->fi_flags & OCFS2_FI_FLAG_SYSFILE)) { + status =3D ocfs2_error(osb->sb, + "Inode %llu: system file state is ambiguous\n", + (unsigned long long)args->fi_blkno); + goto bail; + } =20 if (S_ISCHR(le16_to_cpu(fe->i_mode)) || S_ISBLK(le16_to_cpu(fe->i_mode))) @@ -1520,8 +1524,23 @@ int ocfs2_validate_inode_block(struct super_block *s= b, goto bail; } =20 - if (le16_to_cpu(di->i_suballoc_slot) !=3D (u16)OCFS2_INVALID_SLOT && - (u32)le16_to_cpu(di->i_suballoc_slot) > OCFS2_SB(sb)->max_slots - 1) { + /* + * Only system inodes created by mkfs.ocfs2 are allocated from the + * global allocator and thus legitimately carry OCFS2_INVALID_SLOT. + * Regular inodes are always allocated from a per-slot suballocator. + * If a regular inode with OCFS2_INVALID_SLOT was accepted here, + * deleting it would pass the slot to get_local_system_inode() via + * ocfs2_remove_inode() and trigger BUG_ON(slot =3D=3D OCFS2_INVALID_SLOT= ). + */ + if (le16_to_cpu(di->i_suballoc_slot) =3D=3D (u16)OCFS2_INVALID_SLOT) { + if (!(le32_to_cpu(di->i_flags) & OCFS2_SYSTEM_FL)) { + rc =3D ocfs2_error(sb, + "Invalid dinode %llu: suballoc slot %u for non-system inode\n", + (unsigned long long)bh->b_blocknr, + le16_to_cpu(di->i_suballoc_slot)); + goto bail; + } + } else if ((u32)le16_to_cpu(di->i_suballoc_slot) > OCFS2_SB(sb)->max_slot= s - 1) { rc =3D ocfs2_error(sb, "Invalid dinode %llu: suballoc slot %u\n", (unsigned long long)bh->b_blocknr, le16_to_cpu(di->i_suballoc_slot)); --=20 2.39.3 From nobody Sat Sep 26 16:40:09 2026 Received: from out30-130.freemail.mail.aliyun.com (out30-130.freemail.mail.aliyun.com [115.124.30.130]) (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 605E53242D8 for ; Tue, 1 Sep 2026 12:52:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.130 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788267150; cv=none; b=XY4cqxFbfB9uWjrUvdO8LOp96n+TSkIkRdjywxUS0dYF9Ie8e2EfAi8AiC4O+3aBpXfkoFRKfPdFcdFuErhUFZmyHJcaMhfUL5WzuvQVcheVgbhoMlTMuMtCmsTwxH4T0Mm/KEv2nFlNcvbtb/gSJoKOvJVIYueEXvmVwY9mwgk= ARC-Message-Signature: i=1; a=rsa-sha256; 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a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1788267144; h=From:To:Subject:Date:Message-Id:MIME-Version; bh=cPyHDElzFBExETDV5STE/OBF7qM20J0I8zifjlYmqoc=; b=Yeoevb5CFBD3Ac/VR/2Qof1jDqNYt1gSD51C4dJbIaSBHslMsr340w46TfETaFe5Hf0sSoQCHEVfjSTgUD8gEqogixHjxnTMiPDknAQffJsS9eBicxqEUb8c+A6vDZvNGlxBMmEq3bfmAxF1qNA7V/XssoQBEJe1cPiaaDosf4o= X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R641e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=maildocker-contentspam033037033178;MF=joseph.qi@linux.alibaba.com;NM=1;PH=DS;RN=6;SR=0;TI=SMTPD_---0XA8AofH_1788267143; Received: from localhost(mailfrom:joseph.qi@linux.alibaba.com fp:SMTPD_---0XA8AofH_1788267143 cluster:ay36) by smtp.aliyun-inc.com; Tue, 01 Sep 2026 20:52:24 +0800 From: Joseph Qi To: Andrew Morton , Heming Zhao Cc: Mark Fasheh , Joel Becker , ocfs2-devel@lists.linux.dev, linux-kernel@vger.kernel.org Subject: [PATCH v3 2/4] ocfs2: validate suballoc bit during inode read Date: Tue, 1 Sep 2026 20:52:19 +0800 Message-Id: <20260901125221.1634686-3-joseph.qi@linux.alibaba.com> X-Mailer: git-send-email 2.39.3 In-Reply-To: <20260901125221.1634686-1-joseph.qi@linux.alibaba.com> References: <20260901125221.1634686-1-joseph.qi@linux.alibaba.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" i_suballoc_bit of a dinode is currently not validated at all. A corrupted dinode can carry an abnormally large i_suballoc_bit, which bypasses ocfs2_validate_inode_block(). When the inode is deleted, ocfs2_remove_inode() calls ocfs2_free_dinode(), which passes the unvalidated bit to _ocfs2_free_suballoc_bits() and triggers BUG_ON((count + start_bit) > ocfs2_bits_per_group(cl)). A suballocator block group bitmap is contained in a single block and starts after the group descriptor header, so a valid suballoc bit must be smaller than the number of bits fitting in the remaining space. Reject oversized i_suballoc_bit values during dinode validation. The bound is derived from ocfs2_group_bitmap_size() so it is also tight when discontig_bg caps the suballocator bitmap at OCFS2_MAX_BG_BITMAP_SIZE. Note the above check alone is not sufficient since the freeing path compares the bit against ocfs2_bits_per_group(), which is derived from cl_cpg/cl_bpc of the allocator dinode that is not validated against the actual group capacity and can be artificially smaller on a corrupted image. Convert this BUG_ON in _ocfs2_free_suballoc_bits() to ocfs2_error() as well. Signed-off-by: Joseph Qi --- fs/ocfs2/inode.c | 16 ++++++++++++++++ fs/ocfs2/ocfs2.h | 12 ++++++++++++ fs/ocfs2/suballoc.c | 18 +++++++++++++++--- 3 files changed, 43 insertions(+), 3 deletions(-) diff --git a/fs/ocfs2/inode.c b/fs/ocfs2/inode.c index 9228d6ef23c2..92f3450010fb 100644 --- a/fs/ocfs2/inode.c +++ b/fs/ocfs2/inode.c @@ -1547,6 +1547,22 @@ int ocfs2_validate_inode_block(struct super_block *s= b, goto bail; } =20 + /* + * A suballocator block group bitmap is contained in a single block + * and starts after the group descriptor header, so a valid suballoc + * bit can never exceed ocfs2_suballoc_bits_per_block(). Otherwise + * deleting the inode will pass the oversized bit to + * _ocfs2_free_suballoc_bits() via ocfs2_free_dinode() and trigger + * BUG_ON((count + start_bit) > ocfs2_bits_per_group(cl)), since any + * group holds at most ocfs2_suballoc_bits_per_block() bits. + */ + if (le16_to_cpu(di->i_suballoc_bit) >=3D ocfs2_suballoc_bits_per_block(sb= )) { + rc =3D ocfs2_error(sb, "Invalid dinode %llu: suballoc bit %u\n", + (unsigned long long)bh->b_blocknr, + le16_to_cpu(di->i_suballoc_bit)); + goto bail; + } + if ((le32_to_cpu(di->i_flags) & OCFS2_ORPHANED_FL) && le16_to_cpu(di->i_orphaned_slot) >=3D OCFS2_SB(sb)->max_slots) { rc =3D ocfs2_error(sb, "Invalid dinode %llu: orphaned slot %u\n", diff --git a/fs/ocfs2/ocfs2.h b/fs/ocfs2/ocfs2.h index b747cdec1787..e3bb3cc0b25a 100644 --- a/fs/ocfs2/ocfs2.h +++ b/fs/ocfs2/ocfs2.h @@ -593,6 +593,18 @@ static inline int ocfs2_supports_discontig_bg(struct o= cfs2_super *osb) return 0; } =20 +/* + * A suballocator block group bitmap starts right after the group + * descriptor header, so a suballoc bit can never exceed this number + * of bits. Derive it from ocfs2_group_bitmap_size() which also caps + * it at OCFS2_MAX_BG_BITMAP_SIZE when discontig_bg is enabled. + */ +static inline u32 ocfs2_suballoc_bits_per_block(struct super_block *sb) +{ + return ocfs2_group_bitmap_size(sb, 1, + OCFS2_SB(sb)->s_feature_incompat) * 8; +} + static inline unsigned int ocfs2_link_max(struct ocfs2_super *osb) { if (ocfs2_supports_indexed_dirs(osb)) diff --git a/fs/ocfs2/suballoc.c b/fs/ocfs2/suballoc.c index 453b56be9624..ce22d0c3d287 100644 --- a/fs/ocfs2/suballoc.c +++ b/fs/ocfs2/suballoc.c @@ -3040,10 +3040,22 @@ static int _ocfs2_free_suballoc_bits(handle_t *hand= le, /* The alloc_bh comes from ocfs2_free_dinode() or * ocfs2_free_clusters(). The callers have all locked the * allocator and gotten alloc_bh from the lock call. This - * validates the dinode buffer. Any corruption that has happened - * is a code bug. */ + * validates the dinode buffer. */ BUG_ON(!OCFS2_IS_VALID_DINODE(fe)); - BUG_ON((count + start_bit) > ocfs2_bits_per_group(cl)); + + /* + * ocfs2_bits_per_group() is derived from cl_cpg and cl_bpc of the + * allocator dinode, which are not validated against the volume + * geometry. A corrupted image can carry a suballoc bit beyond it, + * so error out instead of crashing. + */ + if ((count + start_bit) > ocfs2_bits_per_group(cl)) { + return ocfs2_error(alloc_inode->i_sb, + "Allocator #%llu: freeing bits %u+%u exceeds bits per group %u\n", + (unsigned long long)le64_to_cpu(fe->i_blkno), + count, start_bit, + ocfs2_bits_per_group(cl)); + } =20 trace_ocfs2_free_suballoc_bits( (unsigned long long)OCFS2_I(alloc_inode)->ip_blkno, --=20 2.39.3 From nobody Sat Sep 26 16:40:09 2026 Received: from out30-113.freemail.mail.aliyun.com (out30-113.freemail.mail.aliyun.com [115.124.30.113]) (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 1BB5A3B7772 for ; Tue, 1 Sep 2026 12:52:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.113 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788267152; cv=none; b=kgF0CEWporLLa98w/lvo21PVLh9zrXgLwZU2JQ/wPjog/xXyIFm0YaWoYoa9BeCU+FHpA2mXPqfXCjesVeH/s8OY8TnZhhIvpfDCKleMBq7acBYRmPf85uNghiV379H7t/mt+ivnh95IFrxMyfxZYOq4Gp1Ft/2QMbnNxTXSAho= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788267152; c=relaxed/simple; bh=3fdhbvtZHapHmAJHfQZfQ/YhwSthMb3hqixQt20jWMI=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=Iwj3U/Arwyfi0U/hKnNCLNph+7DoSLO535otXYBHtgV4bLoZEY8yKGCdEuZGghsL7p98ZtHBwQLd6B9YK44UeDT1H/j3Yvnfxur3dGSY3nIUdyzJd2d+ypcgno0PB629AGC3xqQDT1yfmfHbHIo0GIzx17XSMCM++B54A/kN70E= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b=mqyltGDW; arc=none smtp.client-ip=115.124.30.113 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b="mqyltGDW" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1788267145; h=From:To:Subject:Date:Message-Id:MIME-Version; bh=7vka9VM/L3gSN7zivj6LmGqDaWWWAAI2Tki83h4L2AE=; b=mqyltGDWYNkrKKJ61aCjXkJ24yHjbTP1Q3Ua78CZFHLoAOKR2/BhdFoCegLIoSUvuU4US1q9GPJVugP/gYsuxUiJOi4DNbpASNWtr1Be1sqEVS3q0Ttq+ZDJ8umU2dqQ9JYqLTO07A+8gVt/VFK5v21mFtsCOaApp7iZcZCraS4= X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R761e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=maildocker-contentspam033045133197;MF=joseph.qi@linux.alibaba.com;NM=1;PH=DS;RN=6;SR=0;TI=SMTPD_---0XA8Sdj1_1788267144; Received: from localhost(mailfrom:joseph.qi@linux.alibaba.com fp:SMTPD_---0XA8Sdj1_1788267144 cluster:ay36) by smtp.aliyun-inc.com; Tue, 01 Sep 2026 20:52:24 +0800 From: Joseph Qi To: Andrew Morton , Heming Zhao Cc: Mark Fasheh , Joel Becker , ocfs2-devel@lists.linux.dev, linux-kernel@vger.kernel.org Subject: [PATCH v3 3/4] ocfs2: validate suballoc slot and bit of xattr and dir index blocks Date: Tue, 1 Sep 2026 20:52:20 +0800 Message-Id: <20260901125221.1634686-4-joseph.qi@linux.alibaba.com> X-Mailer: git-send-email 2.39.3 In-Reply-To: <20260901125221.1634686-1-joseph.qi@linux.alibaba.com> References: <20260901125221.1634686-1-joseph.qi@linux.alibaba.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" ocfs2_validate_xattr_block() and ocfs2_validate_dx_root() do not validate xb_suballoc_slot, xb_suballoc_bit, dr_suballoc_slot and dr_suballoc_bit at all. Since xattr blocks and dir index root blocks are allocated from a per-slot suballocator at runtime, their suballoc slots must be within range and their suballoc bits must fit in a block group bitmap. Otherwise a corrupted image can carry an out-of-range slot. When the xattr block or dir index is removed, ocfs2_xattr_block_remove() or ocfs2_dx_dir_remove_index() passes the unvalidated slot to ocfs2_get_system_file_inode() and get_local_system_inode() will either hit BUG_ON(slot =3D=3D OCFS2_INVALID_SLOT) or compute an out-of-bounds index into the local_system_inodes array. Similarly an oversized suballoc bit will error out the filesystem in _ocfs2_free_suballoc_bits(). Furthermore ocfs2_validate_dx_root() does not verify dr_blkno against the physical block number like the extent and xattr block validators do, so a misplaced dir index root block can pass validation. Reject misplaced dir index root blocks, out-of-range suballoc slots and oversized suballoc bits during validation. Signed-off-by: Joseph Qi --- fs/ocfs2/dir.c | 35 +++++++++++++++++++++++++++++++++++ fs/ocfs2/xattr.c | 25 +++++++++++++++++++++++++ 2 files changed, 60 insertions(+) diff --git a/fs/ocfs2/dir.c b/fs/ocfs2/dir.c index 0075e1624310..6bb6aa133f01 100644 --- a/fs/ocfs2/dir.c +++ b/fs/ocfs2/dir.c @@ -605,6 +605,41 @@ static int ocfs2_validate_dx_root(struct super_block *= sb, goto bail; } =20 + if (le64_to_cpu(dx_root->dr_blkno) !=3D bh->b_blocknr) { + ret =3D ocfs2_error(sb, + "Dir Index Root # %llu has an invalid dr_blkno of %llu\n", + (unsigned long long)bh->b_blocknr, + (unsigned long long)le64_to_cpu(dx_root->dr_blkno)); + goto bail; + } + + /* + * Dir index root blocks are allocated from a per-slot suballocator, + * so the slot must be in range. Otherwise removing the index passes + * it to get_local_system_inode(), which hits BUG_ON() for + * OCFS2_INVALID_SLOT or computes an out-of-bounds index otherwise. + */ + if ((u32)le16_to_cpu(dx_root->dr_suballoc_slot) >=3D OCFS2_SB(sb)->max_sl= ots) { + ret =3D ocfs2_error(sb, + "Dir Index Root # %llu has invalid dr_suballoc_slot %u\n", + (unsigned long long)le64_to_cpu(dx_root->dr_blkno), + le16_to_cpu(dx_root->dr_suballoc_slot)); + goto bail; + } + + /* + * Similarly the suballoc bit must fit in a block group bitmap. + * Otherwise removing the index will pass the oversized bit to + * _ocfs2_free_suballoc_bits() and trigger ocfs2_error() there. + */ + if (le16_to_cpu(dx_root->dr_suballoc_bit) >=3D ocfs2_suballoc_bits_per_bl= ock(sb)) { + ret =3D ocfs2_error(sb, + "Dir Index Root # %llu has invalid dr_suballoc_bit %u\n", + (unsigned long long)le64_to_cpu(dx_root->dr_blkno), + le16_to_cpu(dx_root->dr_suballoc_bit)); + goto bail; + } + if (!(dx_root->dr_flags & OCFS2_DX_FLAG_INLINE)) { struct ocfs2_extent_list *el =3D &dx_root->dr_list; =20 diff --git a/fs/ocfs2/xattr.c b/fs/ocfs2/xattr.c index 143d6f75f9c9..34f102db2a0e 100644 --- a/fs/ocfs2/xattr.c +++ b/fs/ocfs2/xattr.c @@ -532,6 +532,31 @@ static int ocfs2_validate_xattr_block(struct super_blo= ck *sb, le32_to_cpu(xb->xb_fs_generation)); } =20 + /* + * Xattr blocks are allocated from a per-slot suballocator, so the + * slot must be in range. Otherwise freeing the block passes it to + * get_local_system_inode(), which hits BUG_ON() for + * OCFS2_INVALID_SLOT or computes an out-of-bounds index otherwise. + */ + if ((u32)le16_to_cpu(xb->xb_suballoc_slot) >=3D OCFS2_SB(sb)->max_slots) { + return ocfs2_error(sb, + "Extended attribute block #%llu has an invalid xb_suballoc_slot of = %u\n", + (unsigned long long)bh->b_blocknr, + le16_to_cpu(xb->xb_suballoc_slot)); + } + + /* + * Similarly the suballoc bit must fit in a block group bitmap. + * Otherwise freeing the block will pass the oversized bit to + * _ocfs2_free_suballoc_bits() and trigger ocfs2_error() there. + */ + if (le16_to_cpu(xb->xb_suballoc_bit) >=3D ocfs2_suballoc_bits_per_block(s= b)) { + return ocfs2_error(sb, + "Extended attribute block #%llu has an invalid xb_suballoc_bit of %= u\n", + (unsigned long long)bh->b_blocknr, + le16_to_cpu(xb->xb_suballoc_bit)); + } + if (!(le16_to_cpu(xb->xb_flags) & OCFS2_XATTR_INDEXED)) { size_t region_offset =3D offsetof(struct ocfs2_xattr_block, xb_attrs.xb_header); --=20 2.39.3 From nobody Sat Sep 26 16:40:09 2026 Received: from out30-118.freemail.mail.aliyun.com (out30-118.freemail.mail.aliyun.com [115.124.30.118]) (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 1B6AD3DDDB1 for ; Tue, 1 Sep 2026 12:52:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.118 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788267156; cv=none; b=a5LIgqIRHILt+6VtvZm1F1KvwQp8mTN081KPXZCob0OjjScERQD/DJUGKDGNVexJ/W+ZKwYMz2f8cri4CcURAOxkDz7iJnLWjLrCmcn2GlnDvPywshl+5PfrO7LnInxsjAei9sOxx89eKHhspsnQJYGkzeFjPtrbpwU2u3xImNg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788267156; c=relaxed/simple; bh=VwqZK90dxuLVjGg6rgDcQEloreeN/ku+546Mw+4DdCI=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=b0V1vxDOeBg/0NrckGpkYPn6s63Dh6POimM3Oxq4zfrnICrUTB6I8L4kRR3ksSZyzHHm7i+EMwQnig6WVcYAnmusRS18c6oMEQTIfemVXODM6fwmsusaIQNrDmaC8ULcuPHxQsU4J2AlcJCAwIq/rkUYoqP7PjB8vStaGCNWvo8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b=rCR2Fphx; arc=none smtp.client-ip=115.124.30.118 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b="rCR2Fphx" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1788267146; h=From:To:Subject:Date:Message-Id:MIME-Version; bh=lO05Xg2Ij7GojObgHIN9IulfmzcQf0TBixu99pXyXZ0=; b=rCR2FphxkqQRYdRP8SptrDv/R4sf5SDClFpBQZvSVetbHOHAR70m3PespsDXZVdGepYHsSqJohRPFK+QHXxpJnb69Bn9JK+CMiICG/M5jaTZDFqT0aQNWpTu5JliL8q4qk3/ZdkuRCVC3C8InF0sreOtAW6/QB2GlW0WtUFAkcQ= X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R391e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=maildocker-contentspam033037009110;MF=joseph.qi@linux.alibaba.com;NM=1;PH=DS;RN=6;SR=0;TI=SMTPD_---0XA8SdjK_1788267145; Received: from localhost(mailfrom:joseph.qi@linux.alibaba.com fp:SMTPD_---0XA8SdjK_1788267145 cluster:ay36) by smtp.aliyun-inc.com; Tue, 01 Sep 2026 20:52:25 +0800 From: Joseph Qi To: Andrew Morton , Heming Zhao Cc: Mark Fasheh , Joel Becker , ocfs2-devel@lists.linux.dev, linux-kernel@vger.kernel.org Subject: [PATCH v3 4/4] ocfs2: validate suballoc slot and bit of extent and refcount blocks Date: Tue, 1 Sep 2026 20:52:21 +0800 Message-Id: <20260901125221.1634686-5-joseph.qi@linux.alibaba.com> X-Mailer: git-send-email 2.39.3 In-Reply-To: <20260901125221.1634686-1-joseph.qi@linux.alibaba.com> References: <20260901125221.1634686-1-joseph.qi@linux.alibaba.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" ocfs2_validate_extent_block() and ocfs2_validate_refcount_block() do not validate h_suballoc_slot, h_suballoc_bit, rf_suballoc_slot and rf_suballoc_bit at all. Since extent blocks and refcount blocks are allocated from a per-slot suballocator at runtime, their suballoc slots must be within range and their suballoc bits must fit in a block group bitmap. Otherwise a corrupted image can carry an out-of-range slot. When the extent block is freed, ocfs2_cache_extent_block_free() caches it and ocfs2_free_cached_blocks() later passes the unvalidated slot to ocfs2_get_system_file_inode(); when the refcount block is freed, ocfs2_remove_refcount_extent() passes it via ocfs2_cache_block_dealloc(). get_local_system_inode() will then either hit BUG_ON(slot =3D=3D OCFS2_INVALID_SLOT) or compute an out-of-bounds index into the local_system_inodes array. Similarly an oversized suballoc bit will error out the filesystem in _ocfs2_free_suballoc_bits(). Furthermore group descriptor validation only guarantees bg_bits within the physical bitmap size, so a corrupted image can still carry a suballoc bit beyond bg_bits, which would let ocfs2_block_group_clear_bits() clear bits beyond bg_bitmap. Convert the remaining BUG_ON against group->bg_bits in _ocfs2_free_suballoc_bits() to ocfs2_error() as well. Reject out-of-range suballoc slots and oversized suballoc bits during validation. Signed-off-by: Joseph Qi --- fs/ocfs2/alloc.c | 27 +++++++++++++++++++++++++++ fs/ocfs2/refcounttree.c | 27 +++++++++++++++++++++++++++ fs/ocfs2/suballoc.c | 15 ++++++++++++++- 3 files changed, 68 insertions(+), 1 deletion(-) diff --git a/fs/ocfs2/alloc.c b/fs/ocfs2/alloc.c index be09e766ac1f..2fdc5403b10b 100644 --- a/fs/ocfs2/alloc.c +++ b/fs/ocfs2/alloc.c @@ -925,6 +925,33 @@ static int ocfs2_validate_extent_block(struct super_bl= ock *sb, goto bail; } =20 + /* + * Extent blocks are allocated from a per-slot suballocator, so the + * slot must be in range. Otherwise freeing the block passes it to + * get_local_system_inode(), which hits BUG_ON() for + * OCFS2_INVALID_SLOT or computes an out-of-bounds index otherwise. + */ + if ((u32)le16_to_cpu(eb->h_suballoc_slot) >=3D OCFS2_SB(sb)->max_slots) { + rc =3D ocfs2_error(sb, + "Extent block #%llu has an invalid h_suballoc_slot of %u\n", + (unsigned long long)bh->b_blocknr, + le16_to_cpu(eb->h_suballoc_slot)); + goto bail; + } + + /* + * Similarly the suballoc bit must fit in a block group bitmap. + * Otherwise freeing the block will pass the oversized bit to + * _ocfs2_free_suballoc_bits() and trigger ocfs2_error() there. + */ + if (le16_to_cpu(eb->h_suballoc_bit) >=3D ocfs2_suballoc_bits_per_block(sb= )) { + rc =3D ocfs2_error(sb, + "Extent block #%llu has an invalid h_suballoc_bit of %u\n", + (unsigned long long)bh->b_blocknr, + le16_to_cpu(eb->h_suballoc_bit)); + goto bail; + } + if (le16_to_cpu(eb->h_list.l_count) !=3D ocfs2_extent_recs_per_eb(sb)) { rc =3D ocfs2_error(sb, "Extent block #%llu has invalid l_count %u (expected %u)\n", diff --git a/fs/ocfs2/refcounttree.c b/fs/ocfs2/refcounttree.c index d9f22b4a2654..3e9cccf06e48 100644 --- a/fs/ocfs2/refcounttree.c +++ b/fs/ocfs2/refcounttree.c @@ -117,6 +117,33 @@ static int ocfs2_validate_refcount_block(struct super_= block *sb, goto out; } =20 + /* + * Refcount blocks are allocated from a per-slot suballocator, so the + * slot must be in range. Otherwise freeing the block passes it to + * get_local_system_inode(), which hits BUG_ON() for + * OCFS2_INVALID_SLOT or computes an out-of-bounds index otherwise. + */ + if ((u32)le16_to_cpu(rb->rf_suballoc_slot) >=3D OCFS2_SB(sb)->max_slots) { + rc =3D ocfs2_error(sb, + "Refcount block #%llu has an invalid rf_suballoc_slot of %u\n", + (unsigned long long)bh->b_blocknr, + le16_to_cpu(rb->rf_suballoc_slot)); + goto out; + } + + /* + * Similarly the suballoc bit must fit in a block group bitmap. + * Otherwise freeing the block will pass the oversized bit to + * _ocfs2_free_suballoc_bits() and trigger ocfs2_error() there. + */ + if (le16_to_cpu(rb->rf_suballoc_bit) >=3D ocfs2_suballoc_bits_per_block(s= b)) { + rc =3D ocfs2_error(sb, + "Refcount block #%llu has an invalid rf_suballoc_bit of %u\n", + (unsigned long long)bh->b_blocknr, + le16_to_cpu(rb->rf_suballoc_bit)); + goto out; + } + /* * rf_records (rl_count/rl_used/rl_recs[]) is only meaningful when * this block is not an interior tree block (OCFS2_REFCOUNT_TREE_FL); diff --git a/fs/ocfs2/suballoc.c b/fs/ocfs2/suballoc.c index ce22d0c3d287..624152e4f7fe 100644 --- a/fs/ocfs2/suballoc.c +++ b/fs/ocfs2/suballoc.c @@ -3070,7 +3070,20 @@ static int _ocfs2_free_suballoc_bits(handle_t *handl= e, } group =3D (struct ocfs2_group_desc *) group_bh->b_data; =20 - BUG_ON((count + start_bit) > le16_to_cpu(group->bg_bits)); + /* + * Group descriptor validation only guarantees bg_bits within the + * physical bitmap size, so double check the freeing range here. + * Otherwise ocfs2_block_group_clear_bits() would clear bits beyond + * bg_bitmap. + */ + if ((count + start_bit) > le16_to_cpu(group->bg_bits)) { + status =3D ocfs2_error(alloc_inode->i_sb, + "Group descriptor #%llu has %u bits, cannot free bits %u+%u\n", + (unsigned long long)le64_to_cpu(group->bg_blkno), + le16_to_cpu(group->bg_bits), + count, start_bit); + goto bail; + } =20 if (ocfs2_is_cluster_bitmap(alloc_inode)) old_bg_contig_free_bits =3D group->bg_contig_free_bits; --=20 2.39.3