From: ZhengYuan Huang Date: Tue, 12 May 2026 02:41:15 +0000 (+0800) Subject: ocfs2: don't BUG_ON an invalid journal dinode X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c0438198c28b1d22c272751af5e717c11d9fa8dd;p=thirdparty%2Flinux.git ocfs2: don't BUG_ON an invalid journal dinode [BUG] A fuzzed OCFS2 image can corrupt the current slot journal dinode while mount is still in progress. The mount path first reports the invalid journal block and then crashes in shutdown: kernel BUG at fs/ocfs2/journal.c:1034! Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI RIP: 0010:ocfs2_journal_toggle_dirty+0x2d6/0x340 fs/ocfs2/journal.c:1034 Call Trace: ocfs2_journal_shutdown+0x414/0xc30 fs/ocfs2/journal.c:1116 ocfs2_mount_volume fs/ocfs2/super.c:1785 [inline] ocfs2_fill_super+0x30a9/0x3cd0 fs/ocfs2/super.c:1083 get_tree_bdev_flags+0x38b/0x640 fs/super.c:1698 get_tree_bdev+0x24/0x40 fs/super.c:1721 ocfs2_get_tree+0x21/0x30 fs/ocfs2/super.c:1184 vfs_get_tree+0x9a/0x370 fs/super.c:1758 fc_mount fs/namespace.c:1199 [inline] do_new_mount_fc fs/namespace.c:3642 [inline] do_new_mount fs/namespace.c:3718 [inline] path_mount+0x5b8/0x1ea0 fs/namespace.c:4028 do_mount fs/namespace.c:4041 [inline] __do_sys_mount fs/namespace.c:4229 [inline] __se_sys_mount fs/namespace.c:4206 [inline] __x64_sys_mount+0x282/0x320 fs/namespace.c:4206 ... [CAUSE] ocfs2_journal_toggle_dirty() used to return -EIO when journal->j_bh no longer contained a valid dinode, because the startup and shutdown paths already handled that failure. Commit 10995aa2451a ("ocfs2: Morph the haphazard OCFS2_IS_VALID_DINODE() checks.") changed the check to a BUG_ON() under the assumption that the journal dinode had already been validated. That turns an unexpected invalid journal dinode during mount teardown into a kernel crash instead of a normal mount failure. [FIX] Replace the BUG_ON() with WARN_ON() and return -EIO. This keeps the invariant warning for debugging, but restores the original behavior of failing startup or shutdown cleanly instead of panicking the kernel. Link: https://lore.kernel.org/20260512024115.4036371-1-gality369@gmail.com Fixes: 10995aa2451a ("ocfs2: Morph the haphazard OCFS2_IS_VALID_DINODE() checks.") Signed-off-by: ZhengYuan Huang Reviewed-by: Joseph Qi Cc: Mark Fasheh Cc: Joel Becker Cc: Junxiao Bi Cc: Changwei Ge Cc: Jun Piao Cc: Heming Zhao Signed-off-by: Andrew Morton --- diff --git a/fs/ocfs2/journal.c b/fs/ocfs2/journal.c index f9bf3bac085d..fc54cc798ce3 100644 --- a/fs/ocfs2/journal.c +++ b/fs/ocfs2/journal.c @@ -1022,11 +1022,8 @@ static int ocfs2_journal_toggle_dirty(struct ocfs2_super *osb, struct ocfs2_dinode *fe; fe = (struct ocfs2_dinode *)bh->b_data; - - /* The journal bh on the osb always comes from ocfs2_journal_init() - * and was validated there inside ocfs2_inode_lock_full(). It's a - * code bug if we mess it up. */ - BUG_ON(!OCFS2_IS_VALID_DINODE(fe)); + if (WARN_ON(!OCFS2_IS_VALID_DINODE(fe))) + return -EIO; flags = le32_to_cpu(fe->id1.journal1.ij_flags); if (dirty)