diff mbox series

[v1,net,1/2] udplite: Print deprecation notice.

Message ID 20230614194705.90673-2-kuniyu@amazon.com (mailing list archive)
State Accepted
Commit be28c14ac8bbe1ff0b2a18a06cd10981f90fc741
Delegated to: Netdev Maintainers
Headers show
Series udplite/dccp: Print deprecation notice. | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net
netdev/fixes_present fail Series targets non-next tree, but doesn't contain any Fixes tags
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 10 this patch: 10
netdev/cc_maintainers warning 1 maintainers not CCed: dsahern@kernel.org
netdev/build_clang success Errors and warnings before: 8 this patch: 8
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 No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 10 this patch: 10
netdev/checkpatch warning WARNING: quoted string split across lines
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Kuniyuki Iwashima June 14, 2023, 7:47 p.m. UTC 
Recently syzkaller reported a 7-year-old null-ptr-deref [0] that occurs
when a UDP-Lite socket tries to allocate a buffer under memory pressure.

Someone should have stumbled on the bug much earlier if UDP-Lite had been
used in a real app.  Also, we do not always need a large UDP-Lite workload
to hit the bug since UDP and UDP-Lite share the same memory accounting
limit.

Removing UDP-Lite would simplify UDP code removing a bunch of conditionals
in fast path.

Let's add a deprecation notice when UDP-Lite socket is created and schedule
its removal to 2025.

Link: https://lore.kernel.org/netdev/20230523163305.66466-1-kuniyu@amazon.com/ [0]
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
---
 net/ipv4/udplite.c | 2 ++
 net/ipv6/udplite.c | 4 ++++
 2 files changed, 6 insertions(+)
diff mbox series

Patch

diff --git a/net/ipv4/udplite.c b/net/ipv4/udplite.c
index 56d94d23b9e0..143f93a12f25 100644
--- a/net/ipv4/udplite.c
+++ b/net/ipv4/udplite.c
@@ -22,6 +22,8 @@  static int udplite_sk_init(struct sock *sk)
 {
 	udp_init_sock(sk);
 	udp_sk(sk)->pcflag = UDPLITE_BIT;
+	pr_warn_once("UDP-Lite is deprecated and scheduled to be removed in 2025, "
+		     "please contact the netdev mailing list\n");
 	return 0;
 }
 
diff --git a/net/ipv6/udplite.c b/net/ipv6/udplite.c
index 3bab0cc13697..8e010d07917a 100644
--- a/net/ipv6/udplite.c
+++ b/net/ipv6/udplite.c
@@ -8,6 +8,8 @@ 
  *  Changes:
  *  Fixes:
  */
+#define pr_fmt(fmt) "UDPLite6: " fmt
+
 #include <linux/export.h>
 #include <linux/proc_fs.h>
 #include "udp_impl.h"
@@ -16,6 +18,8 @@  static int udplitev6_sk_init(struct sock *sk)
 {
 	udpv6_init_sock(sk);
 	udp_sk(sk)->pcflag = UDPLITE_BIT;
+	pr_warn_once("UDP-Lite is deprecated and scheduled to be removed in 2025, "
+		     "please contact the netdev mailing list\n");
 	return 0;
 }