| Message ID | 1eb3b298-4f7e-32ad-74ae-12044ed637ed@openvz.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | sparse: use force attribute for fmode_t casts | expand |
On Sat 14-05-22 13:22:28, Vasily Averin wrote: > Fixes sparce warnings: > fs/notify/fanotify/fanotify_user.c:267:63: sparse: > warning: restricted fmode_t degrades to integer > fs/notify/fanotify/fanotify_user.c:1351:28: sparse: > warning: restricted fmode_t degrades to integer > fs/proc/base.c:2240:25: sparse: warning: cast to restricted fmode_t > fs/proc/base.c:2297:42: sparse: warning: cast from restricted fmode_t > fs/proc/base.c:2394:48: sparse: warning: cast from restricted fmode_t > fs/open.c:1024:21: sparse: warning: restricted fmode_t degrades to integer > > Signed-off-by: Vasily Averin <vvs@openvz.org> Looks good. Feel free to add: Acked-by: Jan Kara <jack@suse.cz> for the fsnotify related bits. Honza > --- > fs/notify/fanotify/fanotify_user.c | 4 ++-- > fs/open.c | 2 +- > fs/proc/base.c | 6 +++--- > 3 files changed, 6 insertions(+), 6 deletions(-) > > diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c > index 9b32b76a9c30..6b058828e412 100644 > --- a/fs/notify/fanotify/fanotify_user.c > +++ b/fs/notify/fanotify/fanotify_user.c > @@ -264,7 +264,7 @@ static int create_fd(struct fsnotify_group *group, struct path *path, > * originally opened O_WRONLY. > */ > new_file = dentry_open(path, > - group->fanotify_data.f_flags | FMODE_NONOTIFY, > + group->fanotify_data.f_flags | (__force int)FMODE_NONOTIFY, > current_cred()); > if (IS_ERR(new_file)) { > /* > @@ -1348,7 +1348,7 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags) > (!(fid_mode & FAN_REPORT_NAME) || !(fid_mode & FAN_REPORT_FID))) > return -EINVAL; > > - f_flags = O_RDWR | FMODE_NONOTIFY; > + f_flags = O_RDWR | (__force int)FMODE_NONOTIFY; > if (flags & FAN_CLOEXEC) > f_flags |= O_CLOEXEC; > if (flags & FAN_NONBLOCK) > diff --git a/fs/open.c b/fs/open.c > index 1315253e0247..b5ff39ccebfd 100644 > --- a/fs/open.c > +++ b/fs/open.c > @@ -1021,7 +1021,7 @@ inline struct open_how build_open_how(int flags, umode_t mode) > inline int build_open_flags(const struct open_how *how, struct open_flags *op) > { > u64 flags = how->flags; > - u64 strip = FMODE_NONOTIFY | O_CLOEXEC; > + u64 strip = (__force u64)FMODE_NONOTIFY | O_CLOEXEC; > int lookup_flags = 0; > int acc_mode = ACC_MODE(flags); > > diff --git a/fs/proc/base.c b/fs/proc/base.c > index c1031843cc6a..194b5ac069e7 100644 > --- a/fs/proc/base.c > +++ b/fs/proc/base.c > @@ -2237,7 +2237,7 @@ static struct dentry * > proc_map_files_instantiate(struct dentry *dentry, > struct task_struct *task, const void *ptr) > { > - fmode_t mode = (fmode_t)(unsigned long)ptr; > + fmode_t mode = (__force fmode_t)(unsigned long)ptr; > struct proc_inode *ei; > struct inode *inode; > > @@ -2294,7 +2294,7 @@ static struct dentry *proc_map_files_lookup(struct inode *dir, > > if (vma->vm_file) > result = proc_map_files_instantiate(dentry, task, > - (void *)(unsigned long)vma->vm_file->f_mode); > + (void *)(__force unsigned long)vma->vm_file->f_mode); > > out_no_vma: > mmap_read_unlock(mm); > @@ -2391,7 +2391,7 @@ proc_map_files_readdir(struct file *file, struct dir_context *ctx) > buf, len, > proc_map_files_instantiate, > task, > - (void *)(unsigned long)p->mode)) > + (void *)(__force unsigned long)p->mode)) > break; > ctx->pos++; > } > -- > 2.31.1 >
On Sat, May 14, 2022 at 01:22:28PM +0300, Vasily Averin wrote: > Fixes sparce warnings: > fs/notify/fanotify/fanotify_user.c:267:63: sparse: > warning: restricted fmode_t degrades to integer > fs/notify/fanotify/fanotify_user.c:1351:28: sparse: > warning: restricted fmode_t degrades to integer > fs/proc/base.c:2240:25: sparse: warning: cast to restricted fmode_t > fs/proc/base.c:2297:42: sparse: warning: cast from restricted fmode_t > fs/proc/base.c:2394:48: sparse: warning: cast from restricted fmode_t > fs/open.c:1024:21: sparse: warning: restricted fmode_t degrades to integer > > Signed-off-by: Vasily Averin <vvs@openvz.org> > --- > fs/notify/fanotify/fanotify_user.c | 4 ++-- > fs/open.c | 2 +- Looks good to me, Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Please just use __FMODE_NONOTIFY instead, which might be a bit misnamed, but was added exactly for this kind of use. And remember once more: __force casts are a massive code smell. Never add them before thinking hard about them and adding a comment explaining why they can't be avoided, preferably in a dedicated helper.
diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c index 9b32b76a9c30..6b058828e412 100644 --- a/fs/notify/fanotify/fanotify_user.c +++ b/fs/notify/fanotify/fanotify_user.c @@ -264,7 +264,7 @@ static int create_fd(struct fsnotify_group *group, struct path *path, * originally opened O_WRONLY. */ new_file = dentry_open(path, - group->fanotify_data.f_flags | FMODE_NONOTIFY, + group->fanotify_data.f_flags | (__force int)FMODE_NONOTIFY, current_cred()); if (IS_ERR(new_file)) { /* @@ -1348,7 +1348,7 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags) (!(fid_mode & FAN_REPORT_NAME) || !(fid_mode & FAN_REPORT_FID))) return -EINVAL; - f_flags = O_RDWR | FMODE_NONOTIFY; + f_flags = O_RDWR | (__force int)FMODE_NONOTIFY; if (flags & FAN_CLOEXEC) f_flags |= O_CLOEXEC; if (flags & FAN_NONBLOCK) diff --git a/fs/open.c b/fs/open.c index 1315253e0247..b5ff39ccebfd 100644 --- a/fs/open.c +++ b/fs/open.c @@ -1021,7 +1021,7 @@ inline struct open_how build_open_how(int flags, umode_t mode) inline int build_open_flags(const struct open_how *how, struct open_flags *op) { u64 flags = how->flags; - u64 strip = FMODE_NONOTIFY | O_CLOEXEC; + u64 strip = (__force u64)FMODE_NONOTIFY | O_CLOEXEC; int lookup_flags = 0; int acc_mode = ACC_MODE(flags); diff --git a/fs/proc/base.c b/fs/proc/base.c index c1031843cc6a..194b5ac069e7 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -2237,7 +2237,7 @@ static struct dentry * proc_map_files_instantiate(struct dentry *dentry, struct task_struct *task, const void *ptr) { - fmode_t mode = (fmode_t)(unsigned long)ptr; + fmode_t mode = (__force fmode_t)(unsigned long)ptr; struct proc_inode *ei; struct inode *inode; @@ -2294,7 +2294,7 @@ static struct dentry *proc_map_files_lookup(struct inode *dir, if (vma->vm_file) result = proc_map_files_instantiate(dentry, task, - (void *)(unsigned long)vma->vm_file->f_mode); + (void *)(__force unsigned long)vma->vm_file->f_mode); out_no_vma: mmap_read_unlock(mm); @@ -2391,7 +2391,7 @@ proc_map_files_readdir(struct file *file, struct dir_context *ctx) buf, len, proc_map_files_instantiate, task, - (void *)(unsigned long)p->mode)) + (void *)(__force unsigned long)p->mode)) break; ctx->pos++; }
Fixes sparce warnings: fs/notify/fanotify/fanotify_user.c:267:63: sparse: warning: restricted fmode_t degrades to integer fs/notify/fanotify/fanotify_user.c:1351:28: sparse: warning: restricted fmode_t degrades to integer fs/proc/base.c:2240:25: sparse: warning: cast to restricted fmode_t fs/proc/base.c:2297:42: sparse: warning: cast from restricted fmode_t fs/proc/base.c:2394:48: sparse: warning: cast from restricted fmode_t fs/open.c:1024:21: sparse: warning: restricted fmode_t degrades to integer Signed-off-by: Vasily Averin <vvs@openvz.org> --- fs/notify/fanotify/fanotify_user.c | 4 ++-- fs/open.c | 2 +- fs/proc/base.c | 6 +++--- 3 files changed, 6 insertions(+), 6 deletions(-)