| Message ID | 20180122145759.GA18798@kroah.com (mailing list archive) |
|---|---|
| State | Not Applicable |
| Delegated to: | Kalle Valo |
| Headers | show |
On Mon, Jan 22, 2018 at 3:57 PM, Greg KH <gregkh@linuxfoundation.org> wrote: > From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > > It's not good to crash the machine if panic_on_warn() is set just > because someone made a stupid mistake of trying to create a sysfs file > with the same name of an existing one. This makes the automated testing > tools a lot harder to find the real bugs in the kernel. > > So just print a warning out and dump the stack to get the attention of > the developer that they did something foolish. Then keep on trucking, > as this should not be a fatal error at all. > > Reported-by: Dmitry Vyukov <dvyukov@google.com> > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > --- > > Dmitry, does this look good to you? If so, I'll queue it up for > 4.16-rc1. Perfect! Looks good. syzbot reacts on "WARNING:" string (+ if kernel panic due to panic_on_warn that's also obviously a problem). > diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c > index 2b67bda2021b..3a36a48a4b3f 100644 > --- a/fs/sysfs/dir.c > +++ b/fs/sysfs/dir.c > @@ -10,6 +10,7 @@ > * Please see Documentation/filesystems/sysfs.txt for more information. > */ > > +#define pr_fmt(fmt) "sysfs: " fmt > #undef DEBUG > > #include <linux/fs.h> > @@ -27,8 +28,8 @@ void sysfs_warn_dup(struct kernfs_node *parent, const char *name) > if (buf) > kernfs_path(parent, buf, PATH_MAX); > > - WARN(1, KERN_WARNING "sysfs: cannot create duplicate filename '%s/%s'\n", > - buf, name); > + pr_warn("cannot create duplicate filename '%s/%s'\n", buf, name); > + dump_stack(); > > kfree(buf); > }
diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index 2b67bda2021b..3a36a48a4b3f 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -10,6 +10,7 @@ * Please see Documentation/filesystems/sysfs.txt for more information. */ +#define pr_fmt(fmt) "sysfs: " fmt #undef DEBUG #include <linux/fs.h> @@ -27,8 +28,8 @@ void sysfs_warn_dup(struct kernfs_node *parent, const char *name) if (buf) kernfs_path(parent, buf, PATH_MAX); - WARN(1, KERN_WARNING "sysfs: cannot create duplicate filename '%s/%s'\n", - buf, name); + pr_warn("cannot create duplicate filename '%s/%s'\n", buf, name); + dump_stack(); kfree(buf); }