6.1-stable review patch. If anyone has any objections, please let me know.
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From: lei lu llfamsec@gmail.com
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 llfamsec@gmail.com Signed-off-by: Konstantin Komarov almaz.alexandrovich@paragon-software.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/ntfs3/fslog.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
--- a/fs/ntfs3/fslog.c +++ b/fs/ntfs3/fslog.c @@ -724,7 +724,8 @@ static bool check_rstbl(const struct RES
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 RES return false;
off = le32_to_cpu(*(__le32 *)Add2Ptr(rt, off)); + + if (off > ts - sizeof(__le32)) + return false; }
return true;