The patch titled Subject: shmem: use ramfs_kill_sb() for kill_sb method of ramfs-based tmpfs has been added to the -mm mm-unstable branch. Its filename is shmem-use-ramfs_kill_sb-for-kill_sb-method-of-ramfs-based-tmpfs.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/shmem-use-ramfs_kill_sb-for-kill_sb-method-of-ramfs-based-tmpfs.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm 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 via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Roberto Sassu <roberto.sassu@xxxxxxxxxx> Subject: shmem: use ramfs_kill_sb() for kill_sb method of ramfs-based tmpfs Date: Wed, 7 Jun 2023 18:15:23 +0200 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. Link: https://lkml.kernel.org/r/20230607161523.2876433-1-roberto.sassu@xxxxxxxxxxxxxxx Fixes: f32356261d44 ("vfs: Convert ramfs, shmem, tmpfs, devtmpfs, rootfs to use the new mount API") Signed-off-by: Roberto Sassu <roberto.sassu@xxxxxxxxxx> Cc: Hugh Dickins <hughd@xxxxxxxxxx> Cc: David Howells <dhowells@xxxxxxxxxx> Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/ramfs/inode.c | 2 +- include/linux/ramfs.h | 1 + mm/shmem.c | 2 +- 3 files changed, 3 insertions(+), 2 deletions(-) --- a/fs/ramfs/inode.c~shmem-use-ramfs_kill_sb-for-kill_sb-method-of-ramfs-based-tmpfs +++ a/fs/ramfs/inode.c @@ -278,7 +278,7 @@ int ramfs_init_fs_context(struct fs_cont 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); --- a/include/linux/ramfs.h~shmem-use-ramfs_kill_sb-for-kill_sb-method-of-ramfs-based-tmpfs +++ a/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 --- a/mm/shmem.c~shmem-use-ramfs_kill_sb-for-kill_sb-method-of-ramfs-based-tmpfs +++ a/mm/shmem.c @@ -4214,7 +4214,7 @@ static struct file_system_type shmem_fs_ .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, }; _ Patches currently in -mm which might be from roberto.sassu@xxxxxxxxxx are memfd-check-for-non-null-file_seals-in-memfd_create-syscall.patch shmem-use-ramfs_kill_sb-for-kill_sb-method-of-ramfs-based-tmpfs.patch