mhi_alloc_controller() allocates a memory space for mhi_ctrl. When some
errors occur, mhi_ctrl should be freed by mhi_free_controller() and set
ab_pci->mhi_ctrl = NULL because ab_pci->mhi_ctrl has a dangling pointer
to the freed memory. But when ath11k_mhi_read_addr_from_dt() fails, the
function returns without calling mhi_free_controller(), which will lead
to a memory leak.
We can fix it by calling mhi_free_controller() when
ath11k_mhi_read_addr_from_dt() fails and set ab_pci->mhi_ctrl = NULL in
all of the places where we call mhi_free_controller().
Signed-off-by: Jianglei Nie <[email protected]>
---
drivers/net/wireless/ath/ath11k/mhi.c | 17 ++++++++++-------
1 file changed, 10 insertions(+), 7 deletions(-)
diff --git a/drivers/net/wireless/ath/ath11k/mhi.c b/drivers/net/wireless/ath/ath11k/mhi.c
index fc3524e83e52..fc1bbf91c58e 100644
--- a/drivers/net/wireless/ath/ath11k/mhi.c
+++ b/drivers/net/wireless/ath/ath11k/mhi.c
@@ -367,8 +367,7 @@ int ath11k_mhi_register(struct ath11k_pci *ab_pci)
ret = ath11k_mhi_get_msi(ab_pci);
if (ret) {
ath11k_err(ab, "failed to get msi for mhi\n");
- mhi_free_controller(mhi_ctrl);
- return ret;
+ goto free_controller;
}
if (!test_bit(ATH11K_PCI_FLAG_MULTI_MSI_VECTORS, &ab_pci->flags))
@@ -377,7 +376,7 @@ int ath11k_mhi_register(struct ath11k_pci *ab_pci)
if (test_bit(ATH11K_FLAG_FIXED_MEM_RGN, &ab->dev_flags)) {
ret = ath11k_mhi_read_addr_from_dt(mhi_ctrl);
if (ret < 0)
- return ret;
+ goto free_controller;
} else {
mhi_ctrl->iova_start = 0;
mhi_ctrl->iova_stop = 0xFFFFFFFF;
@@ -405,18 +404,22 @@ int ath11k_mhi_register(struct ath11k_pci *ab_pci)
default:
ath11k_err(ab, "failed assign mhi_config for unknown hw rev %d\n",
ab->hw_rev);
- mhi_free_controller(mhi_ctrl);
- return -EINVAL;
+ ret = -EINVAL;
+ goto free_controller;
}
ret = mhi_register_controller(mhi_ctrl, ath11k_mhi_config);
if (ret) {
ath11k_err(ab, "failed to register to mhi bus, err = %d\n", ret);
- mhi_free_controller(mhi_ctrl);
- return ret;
+ goto free_controller;
}
return 0;
+
+free_controller:
+ mhi_free_controller(mhi_ctrl);
+ ab_pci->mhi_ctrl = NULL;
+ return ret;
}
void ath11k_mhi_unregister(struct ath11k_pci *ab_pci)
--
2.25.1
Jianglei Nie <[email protected]> wrote:
> mhi_alloc_controller() allocates a memory space for mhi_ctrl. When some
> errors occur, mhi_ctrl should be freed by mhi_free_controller() and set
> ab_pci->mhi_ctrl = NULL because ab_pci->mhi_ctrl has a dangling pointer
> to the freed memory. But when ath11k_mhi_read_addr_from_dt() fails, the
> function returns without calling mhi_free_controller(), which will lead
> to a memory leak.
>
> We can fix it by calling mhi_free_controller() when
> ath11k_mhi_read_addr_from_dt() fails and set ab_pci->mhi_ctrl = NULL in
> all of the places where we call mhi_free_controller().
>
> Signed-off-by: Jianglei Nie <[email protected]>
Fails to apply, please rebase on top of ath.git master branch:
https://git.kernel.org/pub/scm/linux/kernel/git/kvalo/ath.git/
error: patch failed: drivers/net/wireless/ath/ath11k/mhi.c:367
error: drivers/net/wireless/ath/ath11k/mhi.c: patch does not apply
stg import: Diff does not apply cleanly
Patch set to Changes Requested.
--
https://patchwork.kernel.org/project/linux-wireless/patch/[email protected]/
https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches
On 5/30/2022 1:06 AM, Jianglei Nie wrote:
> mhi_alloc_controller() allocates a memory space for mhi_ctrl. When some
> errors occur, mhi_ctrl should be freed by mhi_free_controller() and set
> ab_pci->mhi_ctrl = NULL because ab_pci->mhi_ctrl has a dangling pointer
> to the freed memory. But when ath11k_mhi_read_addr_from_dt() fails, the
> function returns without calling mhi_free_controller(), which will lead
> to a memory leak.
>
> We can fix it by calling mhi_free_controller() when
> ath11k_mhi_read_addr_from_dt() fails and set ab_pci->mhi_ctrl = NULL in
> all of the places where we call mhi_free_controller().
>
> Signed-off-by: Jianglei Nie <[email protected]>
> ---
> drivers/net/wireless/ath/ath11k/mhi.c | 17 ++++++++++-------
> 1 file changed, 10 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/net/wireless/ath/ath11k/mhi.c b/drivers/net/wireless/ath/ath11k/mhi.c
> index fc3524e83e52..fc1bbf91c58e 100644
> --- a/drivers/net/wireless/ath/ath11k/mhi.c
> +++ b/drivers/net/wireless/ath/ath11k/mhi.c
> @@ -367,8 +367,7 @@ int ath11k_mhi_register(struct ath11k_pci *ab_pci)
> ret = ath11k_mhi_get_msi(ab_pci);
> if (ret) {
> ath11k_err(ab, "failed to get msi for mhi\n");
> - mhi_free_controller(mhi_ctrl);
> - return ret;
> + goto free_controller;
> }
>
> if (!test_bit(ATH11K_PCI_FLAG_MULTI_MSI_VECTORS, &ab_pci->flags))
> @@ -377,7 +376,7 @@ int ath11k_mhi_register(struct ath11k_pci *ab_pci)
> if (test_bit(ATH11K_FLAG_FIXED_MEM_RGN, &ab->dev_flags)) {
> ret = ath11k_mhi_read_addr_from_dt(mhi_ctrl);
> if (ret < 0)
> - return ret;
> + goto free_controller;
> } else {
> mhi_ctrl->iova_start = 0;
> mhi_ctrl->iova_stop = 0xFFFFFFFF;
> @@ -405,18 +404,22 @@ int ath11k_mhi_register(struct ath11k_pci *ab_pci)
> default:
> ath11k_err(ab, "failed assign mhi_config for unknown hw rev %d\n",
> ab->hw_rev);
> - mhi_free_controller(mhi_ctrl);
> - return -EINVAL;
> + ret = -EINVAL;
> + goto free_controller;
> }
>
> ret = mhi_register_controller(mhi_ctrl, ath11k_mhi_config);
> if (ret) {
> ath11k_err(ab, "failed to register to mhi bus, err = %d\n", ret);
> - mhi_free_controller(mhi_ctrl);
> - return ret;
> + goto free_controller;
> }
>
> return 0;
> +
> +free_controller:
> + mhi_free_controller(mhi_ctrl);
> + ab_pci->mhi_ctrl = NULL;
> + return ret;
> }
>
> void ath11k_mhi_unregister(struct ath11k_pci *ab_pci)
LGTM, thanks
Reviewed-by: Jeff Johnson <[email protected]>