From ddf5049ee6f517bd1cac2452a833a58c2830a92f Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Sun, 15 Dec 2024 10:02:37 +0100 Subject: [PATCH] 5.4-stable patches added patches: bpf-sockmap-fix-update-element-with-same.patch --- ...sockmap-fix-update-element-with-same.patch | 57 +++++++++++++++++++ queue-5.4/series | 1 + 2 files changed, 58 insertions(+) create mode 100644 queue-5.4/bpf-sockmap-fix-update-element-with-same.patch diff --git a/queue-5.4/bpf-sockmap-fix-update-element-with-same.patch b/queue-5.4/bpf-sockmap-fix-update-element-with-same.patch new file mode 100644 index 00000000000..b4f83330b87 --- /dev/null +++ b/queue-5.4/bpf-sockmap-fix-update-element-with-same.patch @@ -0,0 +1,57 @@ +From 75e072a390da9a22e7ae4a4e8434dfca5da499fb Mon Sep 17 00:00:00 2001 +From: Michal Luczaj +Date: Mon, 2 Dec 2024 12:29:23 +0100 +Subject: bpf, sockmap: Fix update element with same + +From: Michal Luczaj + +commit 75e072a390da9a22e7ae4a4e8434dfca5da499fb upstream. + +Consider a sockmap entry being updated with the same socket: + + osk = stab->sks[idx]; + sock_map_add_link(psock, link, map, &stab->sks[idx]); + stab->sks[idx] = sk; + if (osk) + sock_map_unref(osk, &stab->sks[idx]); + +Due to sock_map_unref(), which invokes sock_map_del_link(), all the +psock's links for stab->sks[idx] are torn: + + list_for_each_entry_safe(link, tmp, &psock->link, list) { + if (link->link_raw == link_raw) { + ... + list_del(&link->list); + sk_psock_free_link(link); + } + } + +And that includes the new link sock_map_add_link() added just before +the unref. + +This results in a sockmap holding a socket, but without the respective +link. This in turn means that close(sock) won't trigger the cleanup, +i.e. a closed socket will not be automatically removed from the sockmap. + +Stop tearing the links when a matching link_raw is found. + +Fixes: 604326b41a6f ("bpf, sockmap: convert to generic sk_msg interface") +Signed-off-by: Michal Luczaj +Signed-off-by: Daniel Borkmann +Reviewed-by: John Fastabend +Link: https://lore.kernel.org/bpf/20241202-sockmap-replace-v1-1-1e88579e7bd5@rbox.co +Signed-off-by: Greg Kroah-Hartman +--- + net/core/sock_map.c | 1 + + 1 file changed, 1 insertion(+) + +--- a/net/core/sock_map.c ++++ b/net/core/sock_map.c +@@ -152,6 +152,7 @@ static void sock_map_del_link(struct soc + strp_stop = true; + list_del(&link->list); + sk_psock_free_link(link); ++ break; + } + } + spin_unlock_bh(&psock->link_lock); diff --git a/queue-5.4/series b/queue-5.4/series index e5bbf88abb7..c0ea0be4d46 100644 --- a/queue-5.4/series +++ b/queue-5.4/series @@ -4,3 +4,4 @@ usb-dwc2-hcd-fix-getportstatus-setportfeature.patch usb-ehci-hcd-fix-call-balance-of-clocks-handling-routines.patch usb-gadget-u_serial-fix-the-issue-that-gs_start_io-crashed-due-to-accessing-null-pointer.patch xfs-don-t-drop-errno-values-when-we-fail-to-ficlone-the-entire-range.patch +bpf-sockmap-fix-update-element-with-same.patch -- 2.47.3