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Message-ID: <tencent_816D842DE96C309554E8E2ED9ACC6078120A@qq.com>
From: Edward Adam Davis <eadavis@qq.com>
To: syzbot+c48865e11e7e893ec4ab@syzkaller.appspotmail.com
Cc: bfoster@redhat.com,
	kent.overstreet@linux.dev,
	linux-bcachefs@vger.kernel.org,
	linux-fsdevel@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	syzkaller-bugs@googlegroups.com
Subject: [PATCH] bcachefs: fix oob in bch2_sb_clean_to_text
Date: Tue,  7 May 2024 17:19:29 +0800
In-Reply-To: <000000000000918c290617b914ba@google.com>
References: <000000000000918c290617b914ba@google.com>
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When got too small clean field, entry will never equal vstruct_end(&clean->field), 
the dead loop resulted in out of bounds access.

Fixes: 12bf93a429c9 ("bcachefs: Add .to_text() methods for all superblock sections")
Fixes: a37ad1a3aba9 ("bcachefs: sb-clean.c")
Reported-and-tested-by: syzbot+c48865e11e7e893ec4ab@syzkaller.appspotmail.com
Signed-off-by: Edward Adam Davis <eadavis@qq.com>
---
 fs/bcachefs/sb-clean.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/bcachefs/sb-clean.c b/fs/bcachefs/sb-clean.c
index 5980ba2563fe..02101687853e 100644
--- a/fs/bcachefs/sb-clean.c
+++ b/fs/bcachefs/sb-clean.c
@@ -285,7 +285,7 @@ static void bch2_sb_clean_to_text(struct printbuf *out, struct bch_sb *sb,
 	prt_newline(out);
 
 	for (entry = clean->start;
-	     entry != vstruct_end(&clean->field);
+	     entry < vstruct_end(&clean->field);
 	     entry = vstruct_next(entry)) {
 		if (entry->type == BCH_JSET_ENTRY_btree_keys &&
 		    !entry->u64s)
-- 
2.43.0