From 6ae7265a7b816879fd0203e83b5030d3720bbb7a Mon Sep 17 00:00:00 2001 From: lei lu Date: Wed, 29 May 2024 02:52:22 +0800 Subject: [PATCH] fs/ntfs3: Validate ff offset commit 50c47879650b4c97836a0086632b3a2e300b0f06 upstream. This adds sanity checks for ff offset. There is a check on rt->first_free at first, but walking through by ff without any check. If the second ff is a large offset. We may encounter an out-of-bound read. Signed-off-by: lei lu Signed-off-by: Konstantin Komarov Signed-off-by: Greg Kroah-Hartman --- fs/ntfs3/fslog.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/fs/ntfs3/fslog.c b/fs/ntfs3/fslog.c index 2e2348f8e285..c14ab9d5cfc7 100644 --- a/fs/ntfs3/fslog.c +++ b/fs/ntfs3/fslog.c @@ -724,7 +724,8 @@ static bool check_rstbl(const struct RESTART_TABLE *rt, size_t bytes) if (!rsize || rsize > bytes || rsize + sizeof(struct RESTART_TABLE) > bytes || bytes < ts || - le16_to_cpu(rt->total) > ne || ff > ts || lf > ts || + le16_to_cpu(rt->total) > ne || + ff > ts - sizeof(__le32) || lf > ts - sizeof(__le32) || (ff && ff < sizeof(struct RESTART_TABLE)) || (lf && lf < sizeof(struct RESTART_TABLE))) { return false; @@ -754,6 +755,9 @@ static bool check_rstbl(const struct RESTART_TABLE *rt, size_t bytes) return false; off = le32_to_cpu(*(__le32 *)Add2Ptr(rt, off)); + + if (off > ts - sizeof(__le32)) + return false; } return true;