From bb88131c9831075b8dc08cdd375743e5d44c7ca2 Mon Sep 17 00:00:00 2001 From: ZhengYuan Huang Date: Mon, 3 Aug 2026 11:00:07 +0800 Subject: [PATCH] ocfs2: validate DIO orphan slot during inode read [BUG] A corrupted append-DIO dinode (high byte at offset 0xa1 corrupted from 0 to 1) can carry an i_dio_orphaned_slot outside the mounted filesystem slot range and trigger a use-after-free error: BUG: KASAN: slab-use-after-free in ocfs2_get_system_file_inode+0x780/0x820 fs/ocfs2/sysfile.c:102 Read of size 8 at addr ffff88800b767c00 by task kworker/u8:3/85 Call Trace: ... ocfs2_get_system_file_inode+0x780/0x820 fs/ocfs2/sysfile.c:102 ocfs2_wipe_inode+0x292/0xf70 fs/ocfs2/inode.c:840 ocfs2_delete_inode fs/ocfs2/inode.c:1155 [inline] ocfs2_evict_inode+0x6c9/0x1170 fs/ocfs2/inode.c:1295 evict+0x38e/0x8f0 fs/inode.c:810 iput_final fs/inode.c:1914 [inline] iput fs/inode.c:1966 [inline] iput+0x55b/0x8b0 fs/inode.c:1926 ocfs2_recover_orphans+0x610/0xe40 fs/ocfs2/journal.c:2374 ocfs2_complete_recovery+0x5af/0xd00 fs/ocfs2/journal.c:1373 ... [CAUSE] ocfs2_del_inode_from_orphan() uses i_dio_orphaned_slot to index the slot-local system inode cache. The dinode validator does not check this active slot, so an out-of-range value produces an invalid cache entry pointer that is dereferenced as an inode pointer. [FIX] Reject an active i_dio_orphaned_slot outside the slot range during dinode validation, before DIO orphan recovery can consume it. Link: https://lore.kernel.org/20260803030007.3993199-3-gality369@gmail.com Fixes: 06ee5c75b575 ("ocfs2: add functions to add and remove inode in orphan dir") 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 --- fs/ocfs2/inode.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/fs/ocfs2/inode.c b/fs/ocfs2/inode.c index 358ab3535366..180107a11046 100644 --- a/fs/ocfs2/inode.c +++ b/fs/ocfs2/inode.c @@ -1536,6 +1536,14 @@ int ocfs2_validate_inode_block(struct super_block *sb, goto bail; } + if ((le32_to_cpu(di->i_flags) & OCFS2_DIO_ORPHANED_FL) && + le16_to_cpu(di->i_dio_orphaned_slot) >= OCFS2_SB(sb)->max_slots) { + rc = ocfs2_error(sb, "Invalid dinode %llu: DIO orphaned slot %u\n", + (unsigned long long)bh->b_blocknr, + le16_to_cpu(di->i_dio_orphaned_slot)); + goto bail; + } + /* * Reject dinodes whose i_mode does not name one of the seven * canonical POSIX file types. ocfs2_populate_inode() copies