Message ID | 1290557355.2866.117.camel@edumazet-laptop |
---|---|
State | Accepted, archived |
Delegated to: | David Miller |
Headers | show |
From: Eric Dumazet <eric.dumazet@gmail.com> Date: Wed, 24 Nov 2010 01:09:15 +0100 > [PATCH net-next-2.6] net: scm: lower SCM_MAX_FD > > Lower SCM_MAX_FD from 255 to 253 so that allocations for scm_fp_list are > halved. (commit f8d570a4 added two pointers in this structure) > > scm_fp_dup() should not copy whole structure (and trigger kmemcheck > warnings), but only the used part. While we are at it, only allocate > needed size. > > Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Also applied, thanks Eric. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/include/net/scm.h b/include/net/scm.h index 3165650..745460f 100644 --- a/include/net/scm.h +++ b/include/net/scm.h @@ -10,11 +10,12 @@ /* Well, we should have at least one descriptor open * to accept passed FDs 8) */ -#define SCM_MAX_FD 255 +#define SCM_MAX_FD 253 struct scm_fp_list { struct list_head list; - int count; + short count; + short max; struct file *fp[SCM_MAX_FD]; }; diff --git a/net/core/scm.c b/net/core/scm.c index 413cab8..bbe4544 100644 --- a/net/core/scm.c +++ b/net/core/scm.c @@ -79,10 +79,11 @@ static int scm_fp_copy(struct cmsghdr *cmsg, struct scm_fp_list **fplp) return -ENOMEM; *fplp = fpl; fpl->count = 0; + fpl->max = SCM_MAX_FD; } fpp = &fpl->fp[fpl->count]; - if (fpl->count + num > SCM_MAX_FD) + if (fpl->count + num > fpl->max) return -EINVAL; /* @@ -331,11 +332,12 @@ struct scm_fp_list *scm_fp_dup(struct scm_fp_list *fpl) if (!fpl) return NULL; - new_fpl = kmalloc(sizeof(*fpl), GFP_KERNEL); + new_fpl = kmemdup(fpl, offsetof(struct scm_fp_list, fp[fpl->count]), + GFP_KERNEL); if (new_fpl) { - for (i=fpl->count-1; i>=0; i--) + for (i = 0; i < fpl->count; i++) get_file(fpl->fp[i]); - memcpy(new_fpl, fpl, sizeof(*fpl)); + new_fpl->max = new_fpl->count; } return new_fpl; }