2020-06-19 05:24:29

by Tiezhu Yang

Subject: [PATCH] um: vector: Use GFP_ATOMIC under spin lock

Use GFP_ATOMIC instead of GFP_KERNEL under spin lock to fix possible
sleep-in-atomic-context bugs.

Fixes: 9807019a62dc ("um: Loadable BPF "Firmware" for vector drivers")
Signed-off-by: Tiezhu Yang <[email protected]>
---
arch/um/drivers/vector_kern.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/um/drivers/vector_kern.c b/arch/um/drivers/vector_kern.c
index 8735c46..555203e 100644
--- a/arch/um/drivers/vector_kern.c
+++ b/arch/um/drivers/vector_kern.c
@@ -1403,7 +1403,7 @@ static int vector_net_load_bpf_flash(struct net_device *dev,
kfree(vp->bpf->filter);
vp->bpf->filter = NULL;
} else {
- vp->bpf = kmalloc(sizeof(struct sock_fprog), GFP_KERNEL);
+ vp->bpf = kmalloc(sizeof(struct sock_fprog), GFP_ATOMIC);
if (vp->bpf == NULL) {
netdev_err(dev, "failed to allocate memory for firmware\n");
goto flash_fail;
@@ -1415,7 +1415,7 @@ static int vector_net_load_bpf_flash(struct net_device *dev,
if (request_firmware(&fw, efl->data, &vdevice->pdev.dev))
goto flash_fail;

- vp->bpf->filter = kmemdup(fw->data, fw->size, GFP_KERNEL);
+ vp->bpf->filter = kmemdup(fw->data, fw->size, GFP_ATOMIC);
if (!vp->bpf->filter)
goto free_buffer;

--
2.1.0

2020-09-21 15:05:31

by Anton Ivanov

Subject: Re: [PATCH] um: vector: Use GFP_ATOMIC under spin lock

On 19/06/2020 06:20, Tiezhu Yang wrote:
> Use GFP_ATOMIC instead of GFP_KERNEL under spin lock to fix possible
> sleep-in-atomic-context bugs.
>
> Fixes: 9807019a62dc ("um: Loadable BPF "Firmware" for vector drivers")
> Signed-off-by: Tiezhu Yang <[email protected]>
> ---
> arch/um/drivers/vector_kern.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/arch/um/drivers/vector_kern.c b/arch/um/drivers/vector_kern.c
> index 8735c46..555203e 100644
> --- a/arch/um/drivers/vector_kern.c
> +++ b/arch/um/drivers/vector_kern.c
> @@ -1403,7 +1403,7 @@ static int vector_net_load_bpf_flash(struct net_device *dev,
> kfree(vp->bpf->filter);
> vp->bpf->filter = NULL;
> } else {
> - vp->bpf = kmalloc(sizeof(struct sock_fprog), GFP_KERNEL);
> + vp->bpf = kmalloc(sizeof(struct sock_fprog), GFP_ATOMIC);
> if (vp->bpf == NULL) {
> netdev_err(dev, "failed to allocate memory for firmware\n");
> goto flash_fail;
> @@ -1415,7 +1415,7 @@ static int vector_net_load_bpf_flash(struct net_device *dev,
> if (request_firmware(&fw, efl->data, &vdevice->pdev.dev))
> goto flash_fail;
>
> - vp->bpf->filter = kmemdup(fw->data, fw->size, GFP_KERNEL);
> + vp->bpf->filter = kmemdup(fw->data, fw->size, GFP_ATOMIC);
> if (!vp->bpf->filter)
> goto free_buffer;
>
>
Acked-By: Anton Ivanov <[email protected]>
--
Anton R. Ivanov
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