On Sun, Oct 13, 2024 at 2:23 AM Song Liu <song@xxxxxxxxxx> wrote: > > Currently, fsnotify_open_perm() is called from security_file_open(). This > is not right for CONFIG_SECURITY=n and CONFIG_FSNOTIFY=y case, as > security_file_open() in this combination will be a no-op and not call > fsnotify_open_perm(). Fix this by calling fsnotify_open_perm() directly. Maybe I am missing something. I like cleaner interfaces, but if it is a report of a problem then I do not understand what the problem is. IOW, what does "This is not right" mean? > > After this, CONFIG_FANOTIFY_ACCESS_PERMISSIONS does not require > CONFIG_SECURITY any more. Remove the dependency in the config. > > Signed-off-by: Song Liu <song@xxxxxxxxxx> > Acked-by: Paul Moore <paul@xxxxxxxxxxxxxx> > > --- > > v1: https://lore.kernel.org/linux-fsdevel/20241011203722.3749850-1-song@xxxxxxxxxx/ > > As far as I can tell, it is necessary to back port this to stable. Because > CONFIG_FANOTIFY_ACCESS_PERMISSIONS is the only user of fsnotify_open_perm, > and CONFIG_FANOTIFY_ACCESS_PERMISSIONS depends on CONFIG_SECURITY. > Therefore, the following tags are not necessary. But I include here as > these are discussed in v1. I did not understand why you claim that the tags are or not necessary. The dependency is due to removal of the fsnotify.h include. Anyway, I don't think it is critical to backport this fix. The dependencies would probably fail to apply cleanly to older kernels, so unless somebody cares, it would stay this way. > > Fixes: c4ec54b40d33 ("fsnotify: new fsnotify hooks and events types for access decisions") Because I am not sure what the problem is, I am not sure that a Fixes: tag is called for. > Depends-on: 36e28c42187c ("fsnotify: split fsnotify_perm() into two hooks") > Depends-on: d9e5d31084b0 ("fsnotify: optionally pass access range in file permission hooks") These need to be in the commit message in case AUTOSEL or a developer would decide to backport your change. Thanks, Amir. > --- > fs/notify/fanotify/Kconfig | 1 - > fs/open.c | 4 ++++ > security/security.c | 9 +-------- > 3 files changed, 5 insertions(+), 9 deletions(-) > > diff --git a/fs/notify/fanotify/Kconfig b/fs/notify/fanotify/Kconfig > index a511f9d8677b..0e36aaf379b7 100644 > --- a/fs/notify/fanotify/Kconfig > +++ b/fs/notify/fanotify/Kconfig > @@ -15,7 +15,6 @@ config FANOTIFY > config FANOTIFY_ACCESS_PERMISSIONS > bool "fanotify permissions checking" > depends on FANOTIFY > - depends on SECURITY > default n > help > Say Y here is you want fanotify listeners to be able to make permissions > diff --git a/fs/open.c b/fs/open.c > index acaeb3e25c88..6c4950f19cfb 100644 > --- a/fs/open.c > +++ b/fs/open.c > @@ -946,6 +946,10 @@ static int do_dentry_open(struct file *f, > if (error) > goto cleanup_all; > > + error = fsnotify_open_perm(f); > + if (error) > + goto cleanup_all; > + > error = break_lease(file_inode(f), f->f_flags); > if (error) > goto cleanup_all; > diff --git a/security/security.c b/security/security.c > index 6875eb4a59fc..a72cc62c0a07 100644 > --- a/security/security.c > +++ b/security/security.c > @@ -19,7 +19,6 @@ > #include <linux/kernel.h> > #include <linux/kernel_read_file.h> > #include <linux/lsm_hooks.h> > -#include <linux/fsnotify.h> > #include <linux/mman.h> > #include <linux/mount.h> > #include <linux/personality.h> > @@ -3102,13 +3101,7 @@ int security_file_receive(struct file *file) > */ > int security_file_open(struct file *file) > { > - int ret; > - > - ret = call_int_hook(file_open, file); > - if (ret) > - return ret; > - > - return fsnotify_open_perm(file); > + return call_int_hook(file_open, file); > } > > /** > -- > 2.43.5 > >
