Commit edd3cb05 authored by Simon Schuster's avatar Simon Schuster Committed by Christian Brauner
Browse files

copy_process: pass clone_flags as u64 across calltree 



With the introduction of clone3 in commit 7f192e3c ("fork: add
clone3") the effective bit width of clone_flags on all architectures was
increased from 32-bit to 64-bit, with a new type of u64 for the flags.
However, for most consumers of clone_flags the interface was not
changed from the previous type of unsigned long.

While this works fine as long as none of the new 64-bit flag bits
(CLONE_CLEAR_SIGHAND and CLONE_INTO_CGROUP) are evaluated, this is still
undesirable in terms of the principle of least surprise.

Thus, this commit fixes all relevant interfaces of callees to
sys_clone3/copy_process (excluding the architecture-specific
copy_thread) to consistently pass clone_flags as u64, so that
no truncation to 32-bit integers occurs on 32-bit architectures.

Signed-off-by: default avatarSimon Schuster <schuster.simon@siemens-energy.com>
Link: https://lore.kernel.org/20250901-nios2-implement-clone3-v2-2-53fcf5577d57@siemens-energy.com


Acked-by: default avatarDavid Hildenbrand <david@redhat.com>
Reviewed-by: default avatarLorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: default avatarArnd Bergmann <arnd@arndb.de>
Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent 04ff4823

block/blk-ioc.c

+1 −1
Original line number Diff line number Diff line
@@ -286,7 +286,7 @@ int set_task_ioprio(struct task_struct *task, int ioprio) 
}

EXPORT_SYMBOL_GPL(set_task_ioprio);



int __copy_io(unsigned long clone_flags, struct task_struct *tsk)

int __copy_io(u64 clone_flags, struct task_struct *tsk)

{

	struct io_context *ioc = current->io_context;

fs/namespace.c

+1 −1
Original line number Diff line number Diff line
@@ -4200,7 +4200,7 @@ static struct mnt_namespace *alloc_mnt_ns(struct user_namespace *user_ns, bool a 
}



__latent_entropy

struct mnt_namespace *copy_mnt_ns(unsigned long flags, struct mnt_namespace *ns,

struct mnt_namespace *copy_mnt_ns(u64 flags, struct mnt_namespace *ns,

		struct user_namespace *user_ns, struct fs_struct *new_fs)

{

	struct mnt_namespace *new_ns;

include/linux/cgroup.h

+2 −2
Original line number Diff line number Diff line
@@ -796,7 +796,7 @@ extern struct cgroup_namespace init_cgroup_ns; 


void free_cgroup_ns(struct cgroup_namespace *ns);



struct cgroup_namespace *copy_cgroup_ns(unsigned long flags,

struct cgroup_namespace *copy_cgroup_ns(u64 flags,

					struct user_namespace *user_ns,

					struct cgroup_namespace *old_ns);
@@ -818,7 +818,7 @@ static inline void put_cgroup_ns(struct cgroup_namespace *ns) 


static inline void free_cgroup_ns(struct cgroup_namespace *ns) { }

static inline struct cgroup_namespace *

copy_cgroup_ns(unsigned long flags, struct user_namespace *user_ns,

copy_cgroup_ns(u64 flags, struct user_namespace *user_ns,

	       struct cgroup_namespace *old_ns)

{

	return old_ns;

include/linux/cred.h

+1 −1
Original line number Diff line number Diff line
@@ -148,7 +148,7 @@ struct cred { 


extern void __put_cred(struct cred *);

extern void exit_creds(struct task_struct *);

extern int copy_creds(struct task_struct *, unsigned long);

extern int copy_creds(struct task_struct *, u64);

extern const struct cred *get_task_cred(struct task_struct *);

extern struct cred *cred_alloc_blank(void);

extern struct cred *prepare_creds(void);

include/linux/iocontext.h

+3 −3
Original line number Diff line number Diff line
@@ -118,8 +118,8 @@ struct task_struct; 
#ifdef CONFIG_BLOCK

void put_io_context(struct io_context *ioc);

void exit_io_context(struct task_struct *task);

int __copy_io(unsigned long clone_flags, struct task_struct *tsk);

static inline int copy_io(unsigned long clone_flags, struct task_struct *tsk)

int __copy_io(u64 clone_flags, struct task_struct *tsk);

static inline int copy_io(u64 clone_flags, struct task_struct *tsk)

{

	if (!current->io_context)

		return 0;
@@ -129,7 +129,7 @@ static inline int copy_io(unsigned long clone_flags, struct task_struct *tsk) 
struct io_context;

static inline void put_io_context(struct io_context *ioc) { }

static inline void exit_io_context(struct task_struct *task) { }

static inline int copy_io(unsigned long clone_flags, struct task_struct *tsk)

static inline int copy_io(u64 clone_flags, struct task_struct *tsk)

{

	return 0;

}