diff mbox series

[net,v1] netmem: prevent TX of unreadable skbs

Message ID 20250304234924.1583687-1-almasrymina@google.com (mailing list archive)
State New
Delegated to: Netdev Maintainers
Headers show
Series [net,v1] netmem: prevent TX of unreadable skbs | expand

Checks

Context Check Description
netdev/series_format success Single patches do not need cover letters
netdev/tree_selection success Clearly marked for net
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag present in non-next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 0 this patch: 0
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers fail 1 blamed authors not CCed: willemb@google.com; 1 maintainers not CCed: willemb@google.com
netdev/build_clang success Errors and warnings before: 0 this patch: 0
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: 5 this patch: 5
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 9 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 79 this patch: 79
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2025-03-05--06-00 (tests: 894)

Commit Message

Mina Almasry March 4, 2025, 11:49 p.m. UTC
Currently on stable trees we have support for netmem/devmem RX but not
TX. It is not safe to forward/redirect an RX unreadable netmem packet
into the device's TX path, as the device may call dma-mapping APIs on
dma addrs that should not be passed to it.

Fix this by preventing the xmit of unreadable skbs.

Tested by configuring tc redirect:

sudo tc qdisc add dev eth1 ingress
sudo tc filter add dev eth1 ingress protocol ip prio 1 flower ip_proto \
tcp src_ip 192.168.1.12 action mirred egress redirect dev eth1

Before, I see unreadable skbs in the driver's TX path passed to dma
mapping APIs.

After, I don't see unreadable skbs in the driver's TX path passed to dma
mapping APIs.

Fixes: 65249feb6b3d ("net: add support for skbs with unreadable frags")
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Mina Almasry <almasrymina@google.com>
---
 net/core/dev.c | 3 +++
 1 file changed, 3 insertions(+)


base-commit: 3c6a041b317a9bb0c707343c0b99d2a29d523390
diff mbox series

Patch

diff --git a/net/core/dev.c b/net/core/dev.c
index 30da277c5a6f..63b31afacf84 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -3914,6 +3914,9 @@  static struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct net_device
 
 	skb = validate_xmit_xfrm(skb, features, again);
 
+	if (!skb_frags_readable(skb))
+		goto out_kfree_skb;
+
 	return skb;
 
 out_kfree_skb: