[v2] tap: fix write-after-free and double free of intr_handle
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Commit Message
rte_pmd_tun/tap_probe() allocates pmd->intr_handle in eth_dev_tap_create()
and it should not be freed until rte_pmd_tap_remove() is called.
Inspection of tap_rx_intr_vec_set() shows that the call to
tap_tx_intr_vec_uninstall() was calling rte_intr_instance_free() but
tap_tx_intr_vec_install() can then be immediately called, and this then
uses pmd->intr_handle without it being reallocated.
This commit moves the call of rte_intr_instance_free() from
tap_tx_intr_vec_uninstall() to rte_pmd_tap_remove().
Fixes: d61138d4f0e2 ("drivers: remove direct access to interrupt handle")
Changes in v2:
Move rte_intr_instance_free() from tap_rx_intr_vec_uninstall()
to tap_dev_close().
Signed-off-by: Quentin Armitage <quentin@armitage.org.uk>
---
drivers/net/tap/rte_eth_tap.c | 2 ++
drivers/net/tap/tap_intr.c | 2 --
2 files changed, 2 insertions(+), 2 deletions(-)
Comments
On Tue, May 3, 2022 at 8:23 PM Quentin Armitage <quentin@armitage.org.uk> wrote:
>
> rte_pmd_tun/tap_probe() allocates pmd->intr_handle in eth_dev_tap_create()
> and it should not be freed until rte_pmd_tap_remove() is called.
>
> Inspection of tap_rx_intr_vec_set() shows that the call to
> tap_tx_intr_vec_uninstall() was calling rte_intr_instance_free() but
> tap_tx_intr_vec_install() can then be immediately called, and this then
> uses pmd->intr_handle without it being reallocated.
>
> This commit moves the call of rte_intr_instance_free() from
> tap_tx_intr_vec_uninstall() to rte_pmd_tap_remove().
>
> Fixes: d61138d4f0e2 ("drivers: remove direct access to interrupt handle")
Cc: stable@dpdk.org
https://doc.dpdk.org/guides/contributing/patches.html#patch-for-stable-releases
The reason is that backport scripts look for a "Cc: stable@dpdk.org"
in the commitlog itself.
(no need for a v3 just for this, it can be fixed when applying)
>
> Changes in v2:
> Move rte_intr_instance_free() from tap_rx_intr_vec_uninstall()
> to tap_dev_close().
Nit: revisions changelog should be added as annotations (i.e. put
after the --- after the commitlog).
>
> Signed-off-by: Quentin Armitage <quentin@armitage.org.uk>
I did not test the change, but the fix lgtm.
The CI failure from UNH is a false positive.
Reviewed-by: David Marchand <david.marchand@redhat.com>
On 5/4/22 14:17, David Marchand wrote:
> On Tue, May 3, 2022 at 8:23 PM Quentin Armitage <quentin@armitage.org.uk> wrote:
>>
>> rte_pmd_tun/tap_probe() allocates pmd->intr_handle in eth_dev_tap_create()
>> and it should not be freed until rte_pmd_tap_remove() is called.
>>
>> Inspection of tap_rx_intr_vec_set() shows that the call to
>> tap_tx_intr_vec_uninstall() was calling rte_intr_instance_free() but
>> tap_tx_intr_vec_install() can then be immediately called, and this then
>> uses pmd->intr_handle without it being reallocated.
>>
>> This commit moves the call of rte_intr_instance_free() from
>> tap_tx_intr_vec_uninstall() to rte_pmd_tap_remove().
>>
>> Fixes: d61138d4f0e2 ("drivers: remove direct access to interrupt handle")
>
> Cc: stable@dpdk.org
>
> https://doc.dpdk.org/guides/contributing/patches.html#patch-for-stable-releases
> The reason is that backport scripts look for a "Cc: stable@dpdk.org"
> in the commitlog itself.
>
> (no need for a v3 just for this, it can be fixed when applying)
>
>>
>> Changes in v2:
>> Move rte_intr_instance_free() from tap_rx_intr_vec_uninstall()
>> to tap_dev_close().
>
> Nit: revisions changelog should be added as annotations (i.e. put
> after the --- after the commitlog).
>
>
>>
>> Signed-off-by: Quentin Armitage <quentin@armitage.org.uk>
>
> I did not test the change, but the fix lgtm.
> The CI failure from UNH is a false positive.
>
> Reviewed-by: David Marchand <david.marchand@redhat.com>
>
>
Applied with minor fixes in summary and description, thanks.
@@ -1213,6 +1213,8 @@ tap_dev_close(struct rte_eth_dev *dev)
TAP_LOG(DEBUG, "Closing %s Ethernet device on numa %u",
tuntap_types[internals->type], rte_socket_id());
+ rte_intr_instance_free(internals->intr_handle);
+
if (internals->ioctl_sock != -1) {
close(internals->ioctl_sock);
internals->ioctl_sock = -1;
@@ -34,8 +34,6 @@ tap_rx_intr_vec_uninstall(struct rte_eth_dev *dev)
rte_intr_free_epoll_fd(intr_handle);
rte_intr_vec_list_free(intr_handle);
rte_intr_nb_efd_set(intr_handle, 0);
-
- rte_intr_instance_free(intr_handle);
}
/**