* Re: [PATCH net] devlink: uninitialized data in nsim_dev_trap_fa_cookie_write()
2023-07-11 8:52 [PATCH net] devlink: uninitialized data in nsim_dev_trap_fa_cookie_write() Dan Carpenter
@ 2023-07-12 5:29 ` Pavan Chebbi
2023-07-12 8:36 ` Ido Schimmel
` (2 subsequent siblings)
3 siblings, 0 replies; 6+ messages in thread
From: Pavan Chebbi @ 2023-07-12 5:29 UTC (permalink / raw)
To: Dan Carpenter
Cc: Jiri Pirko, Jakub Kicinski, David S. Miller, Eric Dumazet,
Paolo Abeni, Ido Schimmel, netdev, kernel-janitors
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On Tue, Jul 11, 2023 at 2:22 PM Dan Carpenter <dan.carpenter@linaro.org> wrote:
>
> The simple_write_to_buffer() function is designed to handle partial
> writes. It returns negatives on error, otherwise it returns the number
> of bytes that were able to be copied. This code doesn't check the
> return properly. We only know that the first byte is written, the rest
> of the buffer might be uninitialized.
>
> There is no need to use the simple_write_to_buffer() function.
> Partial writes are prohibited by the "if (*ppos != 0)" check at the
> start of the function. Just use memdup_user() and copy the whole
> buffer.
>
> Fixes: d3cbb907ae57 ("netdevsim: add ACL trap reporting cookie as a metadata")
> Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
> ---
> drivers/net/netdevsim/dev.c | 9 +++------
> 1 file changed, 3 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/net/netdevsim/dev.c b/drivers/net/netdevsim/dev.c
> index 6045bece2654..b4d3b9cde8bd 100644
> --- a/drivers/net/netdevsim/dev.c
> +++ b/drivers/net/netdevsim/dev.c
> @@ -184,13 +184,10 @@ static ssize_t nsim_dev_trap_fa_cookie_write(struct file *file,
> cookie_len = (count - 1) / 2;
> if ((count - 1) % 2)
> return -EINVAL;
> - buf = kmalloc(count, GFP_KERNEL | __GFP_NOWARN);
> - if (!buf)
> - return -ENOMEM;
>
> - ret = simple_write_to_buffer(buf, count, ppos, data, count);
> - if (ret < 0)
> - goto free_buf;
> + buf = memdup_user(data, count);
Looks good to me except that now memory comes from GFP_USER.
Within limits it still looks all fine to me.
Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
> + if (IS_ERR(buf))
> + return PTR_ERR(buf);
>
> fa_cookie = kmalloc(sizeof(*fa_cookie) + cookie_len,
> GFP_KERNEL | __GFP_NOWARN);
> --
> 2.39.2
>
>
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^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH net] devlink: uninitialized data in nsim_dev_trap_fa_cookie_write()
2023-07-11 8:52 [PATCH net] devlink: uninitialized data in nsim_dev_trap_fa_cookie_write() Dan Carpenter
2023-07-12 5:29 ` Pavan Chebbi
@ 2023-07-12 8:36 ` Ido Schimmel
2023-07-12 19:48 ` Jakub Kicinski
2023-07-12 21:00 ` patchwork-bot+netdevbpf
3 siblings, 0 replies; 6+ messages in thread
From: Ido Schimmel @ 2023-07-12 8:36 UTC (permalink / raw)
To: Dan Carpenter
Cc: Jiri Pirko, Jakub Kicinski, David S. Miller, Eric Dumazet,
Paolo Abeni, Ido Schimmel, netdev, kernel-janitors
On Tue, Jul 11, 2023 at 11:52:26AM +0300, Dan Carpenter wrote:
> The simple_write_to_buffer() function is designed to handle partial
> writes. It returns negatives on error, otherwise it returns the number
> of bytes that were able to be copied. This code doesn't check the
> return properly. We only know that the first byte is written, the rest
> of the buffer might be uninitialized.
>
> There is no need to use the simple_write_to_buffer() function.
> Partial writes are prohibited by the "if (*ppos != 0)" check at the
> start of the function. Just use memdup_user() and copy the whole
> buffer.
>
> Fixes: d3cbb907ae57 ("netdevsim: add ACL trap reporting cookie as a metadata")
> Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH net] devlink: uninitialized data in nsim_dev_trap_fa_cookie_write()
2023-07-11 8:52 [PATCH net] devlink: uninitialized data in nsim_dev_trap_fa_cookie_write() Dan Carpenter
2023-07-12 5:29 ` Pavan Chebbi
2023-07-12 8:36 ` Ido Schimmel
@ 2023-07-12 19:48 ` Jakub Kicinski
2023-07-13 5:56 ` Dan Carpenter
2023-07-12 21:00 ` patchwork-bot+netdevbpf
3 siblings, 1 reply; 6+ messages in thread
From: Jakub Kicinski @ 2023-07-12 19:48 UTC (permalink / raw)
To: Dan Carpenter
Cc: Jiri Pirko, David S. Miller, Eric Dumazet, Paolo Abeni,
Ido Schimmel, netdev, kernel-janitors
On Tue, 11 Jul 2023 11:52:26 +0300 Dan Carpenter wrote:
> Subject: [PATCH net] devlink: uninitialized data in nsim_dev_trap_fa_cookie_write()
We usually reserve the "devlink: " prefix for net/devlink/ changes
rather than driver changes, so I adjust the subject when applying.
Applied, thanks!
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH net] devlink: uninitialized data in nsim_dev_trap_fa_cookie_write()
2023-07-12 19:48 ` Jakub Kicinski
@ 2023-07-13 5:56 ` Dan Carpenter
0 siblings, 0 replies; 6+ messages in thread
From: Dan Carpenter @ 2023-07-13 5:56 UTC (permalink / raw)
To: Jakub Kicinski
Cc: Jiri Pirko, David S. Miller, Eric Dumazet, Paolo Abeni,
Ido Schimmel, netdev, kernel-janitors
On Wed, Jul 12, 2023 at 12:48:06PM -0700, Jakub Kicinski wrote:
> On Tue, 11 Jul 2023 11:52:26 +0300 Dan Carpenter wrote:
> > Subject: [PATCH net] devlink: uninitialized data in nsim_dev_trap_fa_cookie_write()
>
> We usually reserve the "devlink: " prefix for net/devlink/ changes
> rather than driver changes, so I adjust the subject when applying.
Thanks! I should have seen that, sorry.
regards,
dan carpenter
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH net] devlink: uninitialized data in nsim_dev_trap_fa_cookie_write()
2023-07-11 8:52 [PATCH net] devlink: uninitialized data in nsim_dev_trap_fa_cookie_write() Dan Carpenter
` (2 preceding siblings ...)
2023-07-12 19:48 ` Jakub Kicinski
@ 2023-07-12 21:00 ` patchwork-bot+netdevbpf
3 siblings, 0 replies; 6+ messages in thread
From: patchwork-bot+netdevbpf @ 2023-07-12 21:00 UTC (permalink / raw)
To: Dan Carpenter
Cc: jiri, kuba, davem, edumazet, pabeni, idosch, netdev,
kernel-janitors
Hello:
This patch was applied to netdev/net.git (main)
by Jakub Kicinski <kuba@kernel.org>:
On Tue, 11 Jul 2023 11:52:26 +0300 you wrote:
> The simple_write_to_buffer() function is designed to handle partial
> writes. It returns negatives on error, otherwise it returns the number
> of bytes that were able to be copied. This code doesn't check the
> return properly. We only know that the first byte is written, the rest
> of the buffer might be uninitialized.
>
> There is no need to use the simple_write_to_buffer() function.
> Partial writes are prohibited by the "if (*ppos != 0)" check at the
> start of the function. Just use memdup_user() and copy the whole
> buffer.
>
> [...]
Here is the summary with links:
- [net] devlink: uninitialized data in nsim_dev_trap_fa_cookie_write()
https://git.kernel.org/netdev/net/c/f72207a5c0db
You are awesome, thank you!
--
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html
^ permalink raw reply [flat|nested] 6+ messages in thread