| Message ID | 20240612082936.10867-1-osalvador@suse.de (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | mm/hugetlb: Guard dequeue_hugetlb_folio_nodemask against NUMA_NO_NODE uses | expand |
> On Jun 12, 2024, at 16:29, Oscar Salvador <osalvador@suse.de> wrote: > > dequeue_hugetlb_folio_nodemask() expects a preferred node where to get the > hugetlb page from. > It does not expect, though, users to pass NUMA_NO_NODE, otherwise we will > get trash when trying to get the zonelist from that node. > All current users are careful enough to not pass NUMA_NO_NODE, but > it opens the door for new users to get this wrong since it is not > documented [0]. > Guard against this by getting the local nid if NUMA_NO_NODE was passed. > > [0] https://lore.kernel.org/linux-mm/0000000000004f12bb061a9acf07@google.com/ > > Closes: https://lore.kernel.org/linux-mm/0000000000004f12bb061a9acf07@google.com/ > Reported-and-tested-by: syzbot+569ed13f4054f271087b@syzkaller.appspotmail.com > Signed-off-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: Muchun Song <muchun.song@linux.dev> Thanks.
> dequeue_hugetlb_folio_nodemask() expects a preferred node where to get > the > hugetlb page from. > It does not expect, though, users to pass NUMA_NO_NODE, otherwise we > will > get trash when trying to get the zonelist from that node. > All current users are careful enough to not pass NUMA_NO_NODE, but > it opens the door for new users to get this wrong since it is not > documented [0]. > Guard against this by getting the local nid if NUMA_NO_NODE was passed. > > [0] https://lore.kernel.org/linux- > mm/0000000000004f12bb061a9acf07@google.com/ > > Closes: https://lore.kernel.org/linux- > mm/0000000000004f12bb061a9acf07@google.com/ > Reported-and-tested-by: > syzbot+569ed13f4054f271087b@syzkaller.appspotmail.com > Signed-off-by: Oscar Salvador <osalvador@suse.de> > --- > mm/hugetlb.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/mm/hugetlb.c b/mm/hugetlb.c > index 3518321f6598..6a5ea898e4da 100644 > --- a/mm/hugetlb.c > +++ b/mm/hugetlb.c > @@ -1355,6 +1355,10 @@ static struct folio > *dequeue_hugetlb_folio_nodemask(struct hstate *h, gfp_t gfp_ > struct zoneref *z; > int node = NUMA_NO_NODE; > > + /* 'nid' should not be NUMA_NO_NODE. Try to catch any misuse of it > and rectifiy. */ > + if (nid == NUMA_NO_NODE) > + nid = numa_node_id(); > + > zonelist = node_zonelist(nid, gfp_mask); Acked-by: Vivek Kasireddy <vivek.kasireddy@intel.com> > > retry_cpuset: > -- > 2.45.2
diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 3518321f6598..6a5ea898e4da 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1355,6 +1355,10 @@ static struct folio *dequeue_hugetlb_folio_nodemask(struct hstate *h, gfp_t gfp_ struct zoneref *z; int node = NUMA_NO_NODE; + /* 'nid' should not be NUMA_NO_NODE. Try to catch any misuse of it and rectifiy. */ + if (nid == NUMA_NO_NODE) + nid = numa_node_id(); + zonelist = node_zonelist(nid, gfp_mask); retry_cpuset:
dequeue_hugetlb_folio_nodemask() expects a preferred node where to get the hugetlb page from. It does not expect, though, users to pass NUMA_NO_NODE, otherwise we will get trash when trying to get the zonelist from that node. All current users are careful enough to not pass NUMA_NO_NODE, but it opens the door for new users to get this wrong since it is not documented [0]. Guard against this by getting the local nid if NUMA_NO_NODE was passed. [0] https://lore.kernel.org/linux-mm/0000000000004f12bb061a9acf07@google.com/ Closes: https://lore.kernel.org/linux-mm/0000000000004f12bb061a9acf07@google.com/ Reported-and-tested-by: syzbot+569ed13f4054f271087b@syzkaller.appspotmail.com Signed-off-by: Oscar Salvador <osalvador@suse.de> --- mm/hugetlb.c | 4 ++++ 1 file changed, 4 insertions(+)