diff mbox series

[net-next] net: ethtool: phy: Check the req_info.pdn field for GET commands

Message ID 20240910174636.857352-1-maxime.chevallier@bootlin.com (mailing list archive)
State Accepted
Commit fce1e9f86af13cbd6696ef0c8775990559108f45
Delegated to: Netdev Maintainers
Headers show
Series [net-next] net: ethtool: phy: Check the req_info.pdn field for GET commands | expand

Checks

Context Check Description
netdev/series_format success Single patches do not need cover letters
netdev/tree_selection success Clearly marked for net-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 16 this patch: 16
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers success CCed 6 of 6 maintainers
netdev/build_clang success Errors and warnings before: 16 this patch: 16
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 16 this patch: 16
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 8 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-09-12--00-00 (tests: 764)

Commit Message

Maxime Chevallier Sept. 10, 2024, 5:46 p.m. UTC
When processing the netlink GET requests to get PHY info, the req_info.pdn
pointer is NULL when no PHY matches the requested parameters, such as when
the phy_index is invalid, or there's simply no PHY attached to the
interface.

Therefore, check the req_info.pdn pointer for NULL instead of
dereferencing it.

Suggested-by: Eric Dumazet <edumazet@google.com>
Reported-by: Eric Dumazet <edumazet@google.com>
Closes: https://lore.kernel.org/netdev/CANn89iKRW0WpGAh1tKqY345D8WkYCPm3Y9ym--Si42JZrQAu1g@mail.gmail.com/T/#mfced87d607d18ea32b3b4934dfa18d7b36669285
Fixes: 17194be4c8e1 ("net: ethtool: Introduce a command to list PHYs on an interface")
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
---
Hi,

I'm targetting net-next as the commit this patch fixes is still in
net-next.

 net/ethtool/phy.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Eric Dumazet Sept. 11, 2024, 7:26 a.m. UTC | #1
On Tue, Sep 10, 2024 at 7:46 PM Maxime Chevallier
<maxime.chevallier@bootlin.com> wrote:
>
> When processing the netlink GET requests to get PHY info, the req_info.pdn
> pointer is NULL when no PHY matches the requested parameters, such as when
> the phy_index is invalid, or there's simply no PHY attached to the
> interface.
>
> Therefore, check the req_info.pdn pointer for NULL instead of
> dereferencing it.
>
> Suggested-by: Eric Dumazet <edumazet@google.com>
> Reported-by: Eric Dumazet <edumazet@google.com>
> Closes: https://lore.kernel.org/netdev/CANn89iKRW0WpGAh1tKqY345D8WkYCPm3Y9ym--Si42JZrQAu1g@mail.gmail.com/T/#mfced87d607d18ea32b3b4934dfa18d7b36669285
> Fixes: 17194be4c8e1 ("net: ethtool: Introduce a command to list PHYs on an interface")
> Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
> ---

Thanks, there is another issue found by syzbot BTW (one imbalanced netdev_put())

Reviewed-by: Eric Dumazet <edumazet@google.com>
Maxime Chevallier Sept. 11, 2024, 8:33 a.m. UTC | #2
Hi Eric,

On Wed, 11 Sep 2024 09:26:23 +0200
Eric Dumazet <edumazet@google.com> wrote:

> On Tue, Sep 10, 2024 at 7:46 PM Maxime Chevallier
> <maxime.chevallier@bootlin.com> wrote:
> >
> > When processing the netlink GET requests to get PHY info, the req_info.pdn
> > pointer is NULL when no PHY matches the requested parameters, such as when
> > the phy_index is invalid, or there's simply no PHY attached to the
> > interface.
> >
> > Therefore, check the req_info.pdn pointer for NULL instead of
> > dereferencing it.
> >
> > Suggested-by: Eric Dumazet <edumazet@google.com>
> > Reported-by: Eric Dumazet <edumazet@google.com>
> > Closes: https://lore.kernel.org/netdev/CANn89iKRW0WpGAh1tKqY345D8WkYCPm3Y9ym--Si42JZrQAu1g@mail.gmail.com/T/#mfced87d607d18ea32b3b4934dfa18d7b36669285
> > Fixes: 17194be4c8e1 ("net: ethtool: Introduce a command to list PHYs on an interface")
> > Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
> > ---  
> 
> Thanks, there is another issue found by syzbot BTW (one imbalanced netdev_put())

Sorry for asking that, but I missed the report from this current patch,
as well as the one you're referring to. I've looked-up the netdev
archive and the syzbot web interface [1] and found no reports for both
issues. I am clearly not looking at the right place, and/or I probably
need to open my eyes a bit more.

Can you point me to the report in question ?

[1] : https://syzkaller.appspot.com/upstream/s/net

> 
> Reviewed-by: Eric Dumazet <edumazet@google.com>

Thanks for the review,

Maxime
Maxime Chevallier Sept. 11, 2024, 8:37 a.m. UTC | #3
Hi,

On Wed, 11 Sep 2024 10:33:22 +0200
Maxime Chevallier <maxime.chevallier@bootlin.com> wrote:


> Sorry for asking that, but I missed the report from this current patch,
> as well as the one you're referring to. I've looked-up the netdev
> archive and the syzbot web interface [1] and found no reports for both
> issues. I am clearly not looking at the right place, and/or I probably
> need to open my eyes a bit more.

Heh my bad, I just received the report in question. Looks like you are
getting these before I do :)

Thanks,

Maxime
Eric Dumazet Sept. 11, 2024, 9:20 a.m. UTC | #4
On Wed, Sep 11, 2024 at 10:37 AM Maxime Chevallier
<maxime.chevallier@bootlin.com> wrote:
>
> Hi,
>
> On Wed, 11 Sep 2024 10:33:22 +0200
> Maxime Chevallier <maxime.chevallier@bootlin.com> wrote:
>
>
> > Sorry for asking that, but I missed the report from this current patch,
> > as well as the one you're referring to. I've looked-up the netdev
> > archive and the syzbot web interface [1] and found no reports for both
> > issues. I am clearly not looking at the right place, and/or I probably
> > need to open my eyes a bit more.
>
> Heh my bad, I just received the report in question. Looks like you are
> getting these before I do :)

I triage the reports, to avoid flooding mailing list with duplicates,
and possibly catch very serious security bugs.

I usually wait for some consistent signal like a repro, so that a
single email is sent to the list.
patchwork-bot+netdevbpf@kernel.org Sept. 12, 2024, 12:10 a.m. UTC | #5
Hello:

This patch was applied to netdev/net-next.git (main)
by Jakub Kicinski <kuba@kernel.org>:

On Tue, 10 Sep 2024 19:46:35 +0200 you wrote:
> When processing the netlink GET requests to get PHY info, the req_info.pdn
> pointer is NULL when no PHY matches the requested parameters, such as when
> the phy_index is invalid, or there's simply no PHY attached to the
> interface.
> 
> Therefore, check the req_info.pdn pointer for NULL instead of
> dereferencing it.
> 
> [...]

Here is the summary with links:
  - [net-next] net: ethtool: phy: Check the req_info.pdn field for GET commands
    https://git.kernel.org/netdev/net-next/c/fce1e9f86af1

You are awesome, thank you!
diff mbox series

Patch

diff --git a/net/ethtool/phy.c b/net/ethtool/phy.c
index 560dd039c662..4ef7c6e32d10 100644
--- a/net/ethtool/phy.c
+++ b/net/ethtool/phy.c
@@ -164,7 +164,7 @@  int ethnl_phy_doit(struct sk_buff *skb, struct genl_info *info)
 		goto err_unlock_rtnl;
 
 	/* No PHY, return early */
-	if (!req_info.pdn->phy)
+	if (!req_info.pdn)
 		goto err_unlock_rtnl;
 
 	ret = ethnl_phy_reply_size(&req_info.base, info->extack);