6.18-stable review patch. If anyone has any objections, please let me know.
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From: Edward Adam Davis eadavis@qq.com
[ Upstream commit ccc4e86d1c24260c18ae94541198c3711c140da6 ]
If a rb node with the same ino already exists in the rb tree, the newly alloced mft_inode in ni_add_subrecord() will not have its memory cleaned up, which leads to the memory leak issue reported by syzbot.
The best option to avoid this issue is to put the newly alloced mft node when a rb node with the same ino already exists in the rb tree and return the rb node found in the rb tree to the parent layer.
syzbot reported: BUG: memory leak unreferenced object 0xffff888110bef280 (size 128): backtrace (crc 126a088f): ni_add_subrecord+0x31/0x180 fs/ntfs3/frecord.c:317 ntfs_look_free_mft+0xf0/0x790 fs/ntfs3/fsntfs.c:715
BUG: memory leak unreferenced object 0xffff888109093400 (size 1024): backtrace (crc 7197c55e): mi_init+0x2b/0x50 fs/ntfs3/record.c:105 mi_format_new+0x40/0x220 fs/ntfs3/record.c:422
Fixes: 4342306f0f0d ("fs/ntfs3: Add file operations and implementation") Reported-by: syzbot+3932ccb896e06f7414c9@syzkaller.appspotmail.com Signed-off-by: Edward Adam Davis eadavis@qq.com Signed-off-by: Konstantin Komarov almaz.alexandrovich@paragon-software.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/ntfs3/frecord.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/fs/ntfs3/frecord.c b/fs/ntfs3/frecord.c index a557e3ec0d4c4..e5a005d216f31 100644 --- a/fs/ntfs3/frecord.c +++ b/fs/ntfs3/frecord.c @@ -325,8 +325,10 @@ bool ni_add_subrecord(struct ntfs_inode *ni, CLST rno, struct mft_inode **mi)
mi_get_ref(&ni->mi, &m->mrec->parent_ref);
- ni_add_mi(ni, m); - *mi = m; + *mi = ni_ins_mi(ni, &ni->mi_tree, m->rno, &m->node); + if (*mi != m) + mi_put(m); + return true; }