From: Joerg Roedel <jroe...@suse.de> The iommu_alloc_default_domain() function takes a reference to an IOMMU group without releasing it. This causes the group to never be released, with undefined side effects.
The function has only one call-site, which takes a group reference on its own, so to fix this leak, do not take another reference in iommu_alloc_default_domain() and pass the group as a function parameter instead. Reference: https://lore.kernel.org/lkml/20200522130145.30067-1-saiprakash.ran...@codeaurora.org/ Reported-by: Sai Prakash Ranjan <saiprakash.ran...@codeaurora.org> Cc: Sai Prakash Ranjan <saiprakash.ran...@codeaurora.org> Fixes: 6e1aa2049154 ("iommu: Move default domain allocation to iommu_probe_device()") Signed-off-by: Joerg Roedel <jroe...@suse.de> --- drivers/iommu/iommu.c | 21 +++++++++------------ 1 file changed, 9 insertions(+), 12 deletions(-) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 374b34fd6fac..bf20674769e0 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -80,7 +80,8 @@ static bool iommu_cmd_line_dma_api(void) return !!(iommu_cmd_line & IOMMU_CMD_LINE_DMA_API); } -static int iommu_alloc_default_domain(struct device *dev); +static int iommu_alloc_default_domain(struct iommu_group *group, + struct device *dev); static struct iommu_domain *__iommu_domain_alloc(struct bus_type *bus, unsigned type); static int __iommu_attach_device(struct iommu_domain *domain, @@ -251,17 +252,17 @@ int iommu_probe_device(struct device *dev) if (ret) goto err_out; + group = iommu_group_get(dev); + if (!group) + goto err_release; + /* * Try to allocate a default domain - needs support from the * IOMMU driver. There are still some drivers which don't * support default domains, so the return value is not yet * checked. */ - iommu_alloc_default_domain(dev); - - group = iommu_group_get(dev); - if (!group) - goto err_release; + iommu_alloc_default_domain(group, dev); if (group->default_domain) ret = __iommu_attach_device(group->default_domain, dev); @@ -1478,15 +1479,11 @@ static int iommu_group_alloc_default_domain(struct bus_type *bus, return 0; } -static int iommu_alloc_default_domain(struct device *dev) +static int iommu_alloc_default_domain(struct iommu_group *group, + struct device *dev) { - struct iommu_group *group; unsigned int type; - group = iommu_group_get(dev); - if (!group) - return -ENODEV; - if (group->default_domain) return 0; -- 2.26.2 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
