On Sun, Dec 9, 2018 at 7:52 AM Boris Brezillon <boris.brezillon@xxxxxxxxxxx> wrote: > > On Sat, 20 Oct 2018 19:07:53 +0800 > Hou Tao <houtao1@xxxxxxxxxx> wrote: > > > When jffs2_xattr_ref is dead, xref->ic or xref->xd will be invalid > > because these fields will be reused as xref->ino or xref->xid, > > so access xref->ic->ino or xref->xd->xid will lead to Oops. > > > > Fix the problem by checking whether or not it is a dead xref. > > > > Signed-off-by: Hou Tao <houtao1@xxxxxxxxxx> > > --- > > fs/jffs2/xattr.c | 9 +++++++-- > > 1 file changed, 7 insertions(+), 2 deletions(-) > > > > diff --git a/fs/jffs2/xattr.c b/fs/jffs2/xattr.c > > index 3d40fe02b003..0c4c7891556d 100644 > > --- a/fs/jffs2/xattr.c > > +++ b/fs/jffs2/xattr.c > > @@ -550,7 +550,8 @@ static int save_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref) > > ref->xseqno = xseqno; > > jffs2_add_physical_node_ref(c, phys_ofs | REF_PRISTINE, PAD(sizeof(rr)), (void *)ref); > > > > - dbg_xattr("success on saving xref (ino=%u, xid=%u)\n", ref->ic->ino, ref->xd->xid); > > + dbg_xattr("success on saving xref (ino=%u, xid=%u)\n", > > + je32_to_cpu(rr.ino), je32_to_cpu(rr.xid)); > > Nit: align the second line on the open parens (same applies to the > other chunk). > > Sorry, I can't comment on the actual change. I'll let Richard look > at it. > > > > > return 0; > > } > > @@ -1329,7 +1330,11 @@ int jffs2_garbage_collect_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ > > rc = save_xattr_ref(c, ref); > > if (!rc) > > dbg_xattr("xref (ino=%u, xid=%u) GC'ed from %#08x to %08x\n", > > - ref->ic->ino, ref->xd->xid, old_ofs, ref_offset(ref->node)); > > + is_xattr_ref_dead(ref) ? > > + ref->ino : ref->ic->ino, > > + is_xattr_ref_dead(ref) ? > > + ref->xid : ref->xd->xid, > > + old_ofs, ref_offset(ref->node)); > > out: > > if (!rc) > > jffs2_mark_node_obsolete(c, raw); > Since is_xattr_ref_dead() is cheap, can you please add two macros. Something like: static inline uint32_t xattr_ref_ino(struct jffs2_xattr_ref *ref) { if (is_xattr_ref_dead(ref)) return ref>ino; else return ref->ic->ino; } Same for xid. -- Thanks, //richard ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/