Hi, On 12/16/19 3:24 PM, Qian Cai wrote: > > >> On Nov 26, 2019, at 5:27 AM, Eric Auger <[email protected]> wrote: >> >> In case the new region gets merged into another one, the nr >> list node is freed. Checking its type while completing the >> merge algorithm leads to a use-after-free. Use new->type >> instead. >> >> Fixes: 4dbd258ff63e ("iommu: Revisit iommu_insert_resv_region() >> implementation") >> Signed-off-by: Eric Auger <[email protected]> >> Reported-by: Qian Cai <[email protected]> >> Cc: Stable <[email protected]> #v5.3+ > > > Looks like Joerg is away for a few weeks. Could Andrew or Linus pick up this > use-after-free? Thanks for the heads up. Indeed I was wondering why it hasn't been taken yet.
Note the right version to pick up is the v4, reviewed by Jerry: https://www.mail-archive.com/[email protected]/msg36226.html Thanks Eric > >> >> --- >> >> v2 -> v3: >> - directly use new->type >> >> v1 -> v2: >> - remove spurious new line >> --- >> drivers/iommu/iommu.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c >> index d658c7c6a2ab..285ad4a4c7f2 100644 >> --- a/drivers/iommu/iommu.c >> +++ b/drivers/iommu/iommu.c >> @@ -313,7 +313,7 @@ int iommu_insert_resv_region(struct iommu_resv_region >> *new, >> phys_addr_t top_end, iter_end = iter->start + iter->length - 1; >> >> /* no merge needed on elements of different types than @nr */ >> - if (iter->type != nr->type) { >> + if (iter->type != new->type) { >> list_move_tail(&iter->list, &stack); >> continue; >> } >> -- >> 2.20.1 >> > _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
