Patch "tools: ynl: make sure we always pass yarg to mnl_cb_run" has been added to the 6.6-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    tools: ynl: make sure we always pass yarg to mnl_cb_run

to the 6.6-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     tools-ynl-make-sure-we-always-pass-yarg-to-mnl_cb_ru.patch
and it can be found in the queue-6.6 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit b2b0c38e0ebe0f499ee47ab426a04f1fe3eda41d
Author: Jakub Kicinski <kuba@xxxxxxxxxx>
Date:   Tue Feb 20 08:11:11 2024 -0800

    tools: ynl: make sure we always pass yarg to mnl_cb_run
    
    [ Upstream commit e4fe082c38cd74a8fa384bc7542cf3edf1cb7318 ]
    
    There is one common error handler in ynl - ynl_cb_error().
    It expects priv to be a pointer to struct ynl_parse_arg AKA yarg.
    To avoid potential crashes if we encounter a stray NLMSG_ERROR
    always pass yarg as priv (or a struct which has it as the first
    member).
    
    ynl_cb_null() has a similar problem directly - it expects yarg
    but priv passed by the caller is ys.
    
    Found by code inspection.
    
    Fixes: 86878f14d71a ("tools: ynl: user space helpers")
    Acked-by: Nicolas Dichtel <nicolas.dichtel@xxxxxxxxx>
    Link: https://lore.kernel.org/r/20240220161112.2735195-2-kuba@xxxxxxxxxx
    Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/tools/net/ynl/lib/ynl.c b/tools/net/ynl/lib/ynl.c
index 514e0d69e7310..0a7fe6a13f7b9 100644
--- a/tools/net/ynl/lib/ynl.c
+++ b/tools/net/ynl/lib/ynl.c
@@ -450,6 +450,8 @@ ynl_gemsg_start_dump(struct ynl_sock *ys, __u32 id, __u8 cmd, __u8 version)
 
 int ynl_recv_ack(struct ynl_sock *ys, int ret)
 {
+	struct ynl_parse_arg yarg = { .ys = ys, };
+
 	if (!ret) {
 		yerr(ys, YNL_ERROR_EXPECT_ACK,
 		     "Expecting an ACK but nothing received");
@@ -462,7 +464,7 @@ int ynl_recv_ack(struct ynl_sock *ys, int ret)
 		return ret;
 	}
 	return mnl_cb_run(ys->rx_buf, ret, ys->seq, ys->portid,
-			  ynl_cb_null, ys);
+			  ynl_cb_null, &yarg);
 }
 
 int ynl_cb_null(const struct nlmsghdr *nlh, void *data)
@@ -725,11 +727,14 @@ static int ynl_ntf_parse(struct ynl_sock *ys, const struct nlmsghdr *nlh)
 
 static int ynl_ntf_trampoline(const struct nlmsghdr *nlh, void *data)
 {
-	return ynl_ntf_parse((struct ynl_sock *)data, nlh);
+	struct ynl_parse_arg *yarg = data;
+
+	return ynl_ntf_parse(yarg->ys, nlh);
 }
 
 int ynl_ntf_check(struct ynl_sock *ys)
 {
+	struct ynl_parse_arg yarg = { .ys = ys, };
 	ssize_t len;
 	int err;
 
@@ -751,7 +756,7 @@ int ynl_ntf_check(struct ynl_sock *ys)
 			return len;
 
 		err = mnl_cb_run2(ys->rx_buf, len, ys->seq, ys->portid,
-				  ynl_ntf_trampoline, ys,
+				  ynl_ntf_trampoline, &yarg,
 				  ynl_cb_array, NLMSG_MIN_TYPE);
 		if (err < 0)
 			return err;