diff options
| author |   Tejun Heo <tj@kernel.org> | 2019-11-04 15:54:29 -0800 |
|---|---|---|
| committer | Tejun Heo <tj@kernel.org> | 2019-11-12 08:18:03 -0800 |
| commit | e23f568aa63f64cd6b355094224cc9356c0f696b (patch) | |
| tree | fdefc12ecadf8a7677cf7230613a33d6e86e98e0 /include/linux/kernfs.h | |
| parent | kselftests: cgroup: Avoid the reuse of fd after it is deallocated (diff) | |
| download | linux-dev-e23f568aa63f64cd6b355094224cc9356c0f696b.tar.xz linux-dev-e23f568aa63f64cd6b355094224cc9356c0f696b.zip | |
kernfs: fix ino wrap-around detection
When the 32bit ino wraps around, kernfs increments the generation
number to distinguish reused ino instances. The wrap-around detection
tests whether the allocated ino is lower than what the cursor but the
cursor is pointing to the next ino to allocate so the condition never
triggers.
Fix it by remembering the last ino and comparing against that.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fixes: 4a3ef68acacf ("kernfs: implement i_generation")
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: stable@vger.kernel.org # v4.14+
Diffstat (limited to 'include/linux/kernfs.h')
| -rw-r--r-- | include/linux/kernfs.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/include/linux/kernfs.h b/include/linux/kernfs.h index 936b61bd504e..f797ccc650e7 100644 --- a/include/linux/kernfs.h +++ b/include/linux/kernfs.h @@ -187,6 +187,7 @@ struct kernfs_root { /* private fields, do not use outside kernfs proper */ struct idr ino_idr; + u32 last_ino; u32 next_generation; struct kernfs_syscall_ops *syscall_ops; |