diff options
author | Nicolin Chen <nicolinc@nvidia.com> | 2024-02-22 13:23:45 -0800 |
---|---|---|
committer | Jason Gunthorpe <jgg@nvidia.com> | 2024-02-26 16:58:11 -0400 |
commit | aeb004c0cd6958e910123a1607634401009c9539 (patch) | |
tree | f7716b45546c09ab19bb167cd04d0beeeaf9a737 | |
parent | d206a76d7d2726f3b096037f2079ce0bd3ba329b (diff) |
iommufd: Fix iopt_access_list_id overwrite bug
Syzkaller reported the following WARN_ON:
WARNING: CPU: 1 PID: 4738 at drivers/iommu/iommufd/io_pagetable.c:1360
Call Trace:
iommufd_access_change_ioas+0x2fe/0x4e0
iommufd_access_destroy_object+0x50/0xb0
iommufd_object_remove+0x2a3/0x490
iommufd_object_destroy_user
iommufd_access_destroy+0x71/0xb0
iommufd_test_staccess_release+0x89/0xd0
__fput+0x272/0xb50
__fput_sync+0x4b/0x60
__do_sys_close
__se_sys_close
__x64_sys_close+0x8b/0x110
do_syscall_x64
The mismatch between the access pointer in the list and the passed-in
pointer is resulting from an overwrite of access->iopt_access_list_id, in
iopt_add_access(). Called from iommufd_access_change_ioas() when
xa_alloc() succeeds but iopt_calculate_iova_alignment() fails.
Add a new_id in iopt_add_access() and only update iopt_access_list_id when
returning successfully.
Cc: stable@vger.kernel.org
Fixes: 9227da7816dd ("iommufd: Add iommufd_access_change_ioas(_id) helpers")
Link: https://lore.kernel.org/r/2dda7acb25b8562ec5f1310de828ef5da9ef509c.1708636627.git.nicolinc@nvidia.com
Reported-by: Jason Gunthorpe <jgg@nvidia.com>
Suggested-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
-rw-r--r-- | drivers/iommu/iommufd/io_pagetable.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/drivers/iommu/iommufd/io_pagetable.c b/drivers/iommu/iommufd/io_pagetable.c index 504ac1b01b2d..05fd9d3abf1b 100644 --- a/drivers/iommu/iommufd/io_pagetable.c +++ b/drivers/iommu/iommufd/io_pagetable.c @@ -1330,20 +1330,23 @@ out_unlock: int iopt_add_access(struct io_pagetable *iopt, struct iommufd_access *access) { + u32 new_id; int rc; down_write(&iopt->domains_rwsem); down_write(&iopt->iova_rwsem); - rc = xa_alloc(&iopt->access_list, &access->iopt_access_list_id, access, - xa_limit_16b, GFP_KERNEL_ACCOUNT); + rc = xa_alloc(&iopt->access_list, &new_id, access, xa_limit_16b, + GFP_KERNEL_ACCOUNT); + if (rc) goto out_unlock; rc = iopt_calculate_iova_alignment(iopt); if (rc) { - xa_erase(&iopt->access_list, access->iopt_access_list_id); + xa_erase(&iopt->access_list, new_id); goto out_unlock; } + access->iopt_access_list_id = new_id; out_unlock: up_write(&iopt->iova_rwsem); |