Messages in this thread | | | Date | Wed, 18 Jul 2007 23:57:44 +0900 | From | Tejun Heo <> | Subject | Re: [PATCH] sysfs: kill an extra put in sysfs_create_link() failure path |
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Satyam Sharma wrote: > On 7/18/07, Tejun Heo <htejun@gmail.com> wrote: >> There is a subtle bug in sysfs_create_link() failure path. When >> symlink creation fails because there's already a node with the same >> name, the target sysfs_dirent is put twice - once by failure path of >> sysfs_create_link() and once more when the symlink is released. > > The "symlink" is released? But the creation of the symlink is > precisely what failed here ... did it not? > >> Fix it by making only the symlink node responsible for putting >> target_sd. > > And again ... the changelog sounds confusing indeed, perhaps I'm > not familiar enough with sysfs symlink-related terminology/semantics. > Care to elaborate? > >> sd = sysfs_new_dirent(name, S_IFLNK|S_IRWXUGO, SYSFS_KOBJ_LINK); >> if (!sd) >> goto out_put; >> + >> sd->s_elem.symlink.target_sd = target_sd; >> + target_sd = NULL; /* reference is now owned by the >> symlink */ > > Wow. This looks like a very mysterious way to fix a mysterious bug :-) > BTW I just looked over at sysfs_create_link() and ... it looks quite ... > unnecessarily complicated/obfuscated ...
Well, I dunno. Probably my taste just sucks. Please feel free to submit patches and/or suggest better ideas.
-- tejun - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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