From: Roberto Sassu roberto.sassu@huawei.com
As the ramfs-based tmpfs uses ramfs_init_fs_context() for the init_fs_context method, which allocates fc->s_fs_info, use ramfs_kill_sb() to free it and avoid a memory leak.
Cc: stable@vger.kernel.org # v5.4.x Fixes: f32356261d44 ("vfs: Convert ramfs, shmem, tmpfs, devtmpfs, rootfs to use the new mount API") Signed-off-by: Roberto Sassu roberto.sassu@huawei.com --- fs/ramfs/inode.c | 2 +- include/linux/ramfs.h | 1 + mm/shmem.c | 2 +- 3 files changed, 3 insertions(+), 2 deletions(-)
diff --git a/fs/ramfs/inode.c b/fs/ramfs/inode.c index 5ba580c7883..fef477c7810 100644 --- a/fs/ramfs/inode.c +++ b/fs/ramfs/inode.c @@ -278,7 +278,7 @@ int ramfs_init_fs_context(struct fs_context *fc) return 0; }
-static void ramfs_kill_sb(struct super_block *sb) +void ramfs_kill_sb(struct super_block *sb) { kfree(sb->s_fs_info); kill_litter_super(sb); diff --git a/include/linux/ramfs.h b/include/linux/ramfs.h index 917528d102c..d506dc63dd4 100644 --- a/include/linux/ramfs.h +++ b/include/linux/ramfs.h @@ -7,6 +7,7 @@ struct inode *ramfs_get_inode(struct super_block *sb, const struct inode *dir, umode_t mode, dev_t dev); extern int ramfs_init_fs_context(struct fs_context *fc); +extern void ramfs_kill_sb(struct super_block *sb);
#ifdef CONFIG_MMU static inline int diff --git a/mm/shmem.c b/mm/shmem.c index e40a08c5c6d..74abb97ea55 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -4196,7 +4196,7 @@ static struct file_system_type shmem_fs_type = { .name = "tmpfs", .init_fs_context = ramfs_init_fs_context, .parameters = ramfs_fs_parameters, - .kill_sb = kill_litter_super, + .kill_sb = ramfs_kill_sb, .fs_flags = FS_USERNS_MOUNT, };