Hi Jingbo,
On 2024/4/22 18:25, Jingbo Xu wrote:
On 4/19/24 8:36 PM, Baokun Li wrote:
@@ -761,12 +747,15 @@ static void erofs_free_dev_context(struct
erofs_dev_context *devs)
static void erofs_fc_free(struct fs_context *fc)
{
- struct erofs_fs_context *ctx = fc->fs_private;
+ struct erofs_sb_info *sbi = fc->s_fs_info;
+
+ if (!sbi)
+ return;
This is the only difference comparing to the original code literally.
Is there any chance that fc->s_fs_info can be NULL when erofs_fc_free()
is called?
Otherwise looks good to me.
When sget_fc() executes successfully, fc->s_fs_info is set to NULL,
so the following NULL pointer dereference may occur:
do_new_mount
vfs_get_tree
erofs_fc_get_tree
get_tree_bdev
sget_dev
sget_fc
s = alloc_super
s->s_fs_info = fc->s_fs_info;
fc->s_fs_info = NULL;
fill_super
// return error
deactivate_locked_super
kfree(sbi);
put_fs_context
sbi = fc->s_fs_info
kfree(sbi->fsid)
Thank you very much for the review!
--
With Best Regards,
Baokun Li
