The patch titled
Subject: ocfs2: fix potential use after free
has been added to the -mm tree. Its filename is
ocfs2-fix-potential-use-after-free.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/ocfs2-fix-potential-use-after-free.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/ocfs2-fix-potential-use-after-free.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Pan Bian <bianpan2016@xxxxxxx>
Subject: ocfs2: fix potential use after free
ocfs2_get_dentry() calls iput(inode) to drop the reference count of inode,
and if the reference count hits 0, inode is freed. However, in this
function, it then reads inode->i_generation, which may result in a use
after free bug. Move the put operation later.
Link: http://lkml.kernel.org/r/1543109237-110227-1-git-send-email-bianpan2016@xxxxxxx
Fixes: 781f200cb7a("ocfs2: Remove masklog ML_EXPORT.")
Signed-off-by: Pan Bian <bianpan2016@xxxxxxx>
Reviewed-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Mark Fasheh <mark@xxxxxxxxxx>
Cc: Joel Becker <jlbec@xxxxxxxxxxxx>
Cc: Junxiao Bi <junxiao.bi@xxxxxxxxxx>
Cc: Joseph Qi <jiangqi903@xxxxxxxxx>
Cc: Changwei Ge <ge.changwei@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/ocfs2/export.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/fs/ocfs2/export.c~ocfs2-fix-potential-use-after-free
+++ a/fs/ocfs2/export.c
@@ -125,10 +125,10 @@ check_err:
check_gen:
if (handle->ih_generation != inode->i_generation) {
- iput(inode);
trace_ocfs2_get_dentry_generation((unsigned long long)blkno,
handle->ih_generation,
inode->i_generation);
+ iput(inode);
result = ERR_PTR(-ESTALE);
goto bail;
}
_
Patches currently in -mm which might be from bianpan2016@xxxxxxx are
hfs-do-not-free-node-before-using.patch
hfsplus-do-not-free-node-before-using.patch
ocfs2-fix-potential-use-after-free.patch
