From nobody Sun Feb 8 04:13:23 2026 Received: from mail-pf1-f174.google.com (mail-pf1-f174.google.com [209.85.210.174]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2B59E3EBF20 for ; Sat, 24 Jan 2026 05:01:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.174 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769230895; cv=none; b=gInGlNcKjJ+VCY0sRd3HFn5kvKZJuAt/K164YlToh0Rqpf5hn9RfkF0mnRZ3UaTDYPvloYrYLFDPr3rib/mt/BljLTzwYtxtudv4SfK9jz2AhWcSh+d+E+kZQNy6EQKHcFv6Ud4u97TBe3bCGtokMAorhqWjXhiCIgXGrknG110= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769230895; c=relaxed/simple; bh=NuxKESorXkkj2kfNbIrVK8CRosZqJ8200rvI2f4jcqk=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=oD2UeaoPYbQ6h3/jbBfM2lcFYhEK5mWKIWUvEJXwEhpo71kikFiudU88sOP57uGokp54O4+jNSMHHlxARZYs/8zC0V+v6yHae4LVQk1CcVtiQuY2DHbjTif8MKCQE4beMrW/h+Nycra7niJxztOYm4ipJaOzJlxPf2vFO0FNxDQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=mTL26q3O; arc=none smtp.client-ip=209.85.210.174 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="mTL26q3O" Received: by mail-pf1-f174.google.com with SMTP id d2e1a72fcca58-8230f2140beso1022217b3a.1 for ; Fri, 23 Jan 2026 21:01:33 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1769230893; x=1769835693; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=E2YX76ut4F4+pCFown4SbvAuNnVLkheLVcPXYOrLSEg=; b=mTL26q3O72Nkh6G+T0dCDMWWtotARt2H+1mzi1mNkc45sOHOCUgTMrbi6Qx9p7s5RH 8EVtQgnurBaCtGnxmpQR2gBTaNV9WU3vMaH/eLfqahz2HnGuYiS4QoMvMzj1wt3GKm49 /4qwSs9viUoROxn+08J233IIjUXaSn6j7grFpPK1zZSIXrOQBLrFV30+2ZfdcioszXcn ZWnNLH/sL7AR3gFv2JTxiMxXR1RGUBQUScNCNh4d2uVg++q2ghOlcm4T6iKDInoyFerd 8GAv3fPZEwW7VYb4PxQv5NDv7cb6iVy9MK1oY0LCCOpF5XOSKwwr38RY/Dqdyp3J0vIF v4sg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1769230893; x=1769835693; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=E2YX76ut4F4+pCFown4SbvAuNnVLkheLVcPXYOrLSEg=; b=pYOEihfVGbB3W+CYAZTpKOxonnliwtvkRSv87aRi4lvgWYcd82pIKq0CVG3+1+7YcU gqtgbcFlUudPGUIEIONUinrBz3srMLZVwX9zZGsd8ABWDu/eig10mX2qAZ6+OFGmLD0b T1k71PmZf4RpfOBrCm29RoNogToBJ5GPR/69vIf1rKxwvFzHKRQuEW2skJtNk0GmfkyI s9gfYh64W1gYeuAW5+zIFwqeUJVWH8HtadN0GqHKEu8GLAaJcDeoVVftW3E+kEohtD2j d/pN9yK8X75mPyMv0gKXtr4Ryz1C1zQm/0cjoxW+eDQkpFmwvzMVICcUdVahocLVJczh fYkw== X-Forwarded-Encrypted: i=1; AJvYcCWe+2NnuVAWmREOhOcpWs/3lfMdoN9ldOxKMk0jsjISZWDKiBhz5AHqNYZuJh4X38ToYLMJT3xnEwKOObY=@vger.kernel.org X-Gm-Message-State: AOJu0Yx1yCYT/7Vv/U/wtQhE3ZQHdfOTKkeNWtzWh6sysI86eA2BpXnS uqlKCKAr3yjZzHXEqQ2rU7ppCR/38SYWrmXU3h88Zs9Bo2B01D9Fn/Rm X-Gm-Gg: AZuq6aIEoR+zsOh7qGKN5UDnqoMpA5D+lZyXg1RaqBpd5Cjl5eI/9B11n0/0I2hz6Ya O9hd3zIatE6RsOEm8PC5W1XjMnowNRaSNF+c14tNrFmq2ANoawU9AWIc33HDnkoWYCqyqqdsXnb 6BR3A/wA8EuLJ9TipoWm7lZDnZXC7zoUM0ezSZ+dpzIxmmPgZwtgzXWLYVt3oo98Yl3wm6fVHIO D/M/g2TPFn34uowgdsawpubGly4Bd7M//U++9FPGXx+gDHMEYKVe7LP6Tim1fJDCqM0Nn5JOaii PpZovbbw7sXJnSfzIVuBXc75jXt8Fbm/pPG6poETAuV0SHlMxFvX8xg8viHIeKmDyy5N+g68QCo mQxNx434F7kqv+WzZJ99qTs+RSC8jM2ETBPdDFGK1rr8K4+HDbpLPw+CSwOwM38g+acIoOdiaCe KZFarzu4E/TUeqq8lHi/Fkmv4ki0kwXiSS6UcS6QjdkS36+8gy/wgpfD2TMNsLUB4cA4E= X-Received: by 2002:a05:6a00:1823:b0:81f:4e1c:1d3b with SMTP id d2e1a72fcca58-82317b304c6mr4649165b3a.23.1769230893292; Fri, 23 Jan 2026 21:01:33 -0800 (PST) Received: from deepanshu-kernel-hacker.. ([2405:201:682f:389d:db06:8149:7b0d:66a3]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-8231873e632sm3546744b3a.46.2026.01.23.21.01.29 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 23 Jan 2026 21:01:32 -0800 (PST) From: Deepanshu Kartikey To: mark@fasheh.com, jlbec@evilplan.org, joseph.qi@linux.alibaba.com Cc: ocfs2-devel@lists.linux.dev, linux-kernel@vger.kernel.org, Deepanshu Kartikey , syzbot+44c564a3cb08605f34a1@syzkaller.appspotmail.com Subject: [PATCH v3] ocfs2: validate i_blkno and BITMAP_FL consistency in ocfs2_validate_inode_block Date: Sat, 24 Jan 2026 10:31:24 +0530 Message-ID: <20260124050124.27926-1-kartikey406@gmail.com> X-Mailer: git-send-email 2.43.0 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_is_cluster_bitmap() checks whether an inode is the global bitmap by comparing ip_blkno with osb->bitmap_blkno. A corrupted filesystem can have an inode with i_blkno and OCFS2_BITMAP_FL flag inconsistent: - i_blkno matches bitmap_blkno but BITMAP_FL is not set, or - BITMAP_FL is set but i_blkno does not match bitmap_blkno In either case, ocfs2_is_cluster_bitmap() returns incorrect results, triggering BUG_ON in ocfs2_block_group_search() or ocfs2_cluster_group_search() causing a kernel panic. Call trace: ocfs2_block_group_search+0x1c7/0x2c0 fs/ocfs2/suballoc.c:1611 ocfs2_search_chain+0x38a/0x1010 fs/ocfs2/suballoc.c:1764 ocfs2_claim_suballoc_bits+0x3a4/0x650 fs/ocfs2/suballoc.c:1978 ocfs2_claim_new_inode+0x95/0x130 fs/ocfs2/suballoc.c:2137 ocfs2_mknod_locked+0x129/0x510 fs/ocfs2/namei.c:568 ocfs2_mknod+0x5c7/0x11d0 fs/ocfs2/namei.c:802 ocfs2_create+0x136/0x170 fs/ocfs2/namei.c:852 Add validation in ocfs2_validate_inode_block() to check that i_blkno and OCFS2_BITMAP_FL are consistent: - If i_blkno matches bitmap_blkno, BITMAP_FL must be set - If BITMAP_FL is set, i_blkno must match bitmap_blkno This catches corrupted inodes early when reading from disk. Reported-by: syzbot+44c564a3cb08605f34a1@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=3D44c564a3cb08605f34a1 Tested-by: syzbot+44c564a3cb08605f34a1@syzkaller.appspotmail.com Link: https://lore.kernel.org/all/20260104014028.305029-1-kartikey406@gmail= .com/T/ [v1] Link: https://lore.kernel.org/all/20260110054443.604944-1-kartikey406@gmail= .com/T/ [v2] Signed-off-by: Deepanshu Kartikey --- v3: - Move validation to ocfs2_validate_inode_block() to catch corruption early when inode is read from disk (Joseph Qi) - Add check for both directions of inconsistency v2: - Fix commit message - ocfs2_is_cluster_bitmap() checks ip_blkno against bitmap_blkno, not a flag (Joseph Qi) --- fs/ocfs2/inode.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/fs/ocfs2/inode.c b/fs/ocfs2/inode.c index b5fcc2725a29..2d80934d14b4 100644 --- a/fs/ocfs2/inode.c +++ b/fs/ocfs2/inode.c @@ -1529,6 +1529,27 @@ int ocfs2_validate_inode_block(struct super_block *s= b, } } =20 + /* + * Validate bitmap flag consistency with bitmap_blkno. + * A corrupted inode with mismatched i_blkno and BITMAP_FL would + * cause ocfs2_is_cluster_bitmap() to return incorrect results, + * triggering BUG_ON in ocfs2_block_group_search() or + * ocfs2_cluster_group_search(). + */ + if (le64_to_cpu(di->i_blkno) =3D=3D OCFS2_SB(sb)->bitmap_blkno && + !(di->i_flags & cpu_to_le32(OCFS2_BITMAP_FL))) { + rc =3D ocfs2_error(sb, + "Invalid dinode #%llu: i_blkno matches bitmap but BITMAP flag not set= \n", + (unsigned long long)bh->b_blocknr); + goto bail; + } else if (di->i_flags & cpu_to_le32(OCFS2_BITMAP_FL) && + le64_to_cpu(di->i_blkno) !=3D OCFS2_SB(sb)->bitmap_blkno) { + rc =3D ocfs2_error(sb, + "Invalid dinode #%llu: BITMAP flag set but i_blkno does not match bit= map\n", + (unsigned long long)bh->b_blocknr); + goto bail; + } + rc =3D 0; =20 bail: --=20 2.43.0