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Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , netfilter-devel@vger.kernel.org, coreteam@netfilter.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org, Tristan Madani References: <20260527135751.1031891-1-tristmd@gmail.com> Content-Language: en-US From: Fernando Fernandez Mancera In-Reply-To: <20260527135751.1031891-1-tristmd@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Level: X-Rspamd-Server: rspamd2.dmz-prg2.suse.org X-Rspamd-Queue-Id: 5EE1A67161 X-Rspamd-Action: no action X-Spamd-Result: default: False [-4.51 / 50.00]; BAYES_HAM(-3.00)[99.99%]; NEURAL_HAM_LONG(-1.00)[-1.000]; R_DKIM_ALLOW(-0.20)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; NEURAL_HAM_SHORT(-0.20)[-0.988]; MIME_GOOD(-0.10)[text/plain]; MX_GOOD(-0.01)[]; FREEMAIL_TO(0.00)[gmail.com,netfilter.org,strlen.de]; FUZZY_RATELIMITED(0.00)[rspamd.com]; ARC_NA(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; RCPT_COUNT_TWELVE(0.00)[15]; MIME_TRACE(0.00)[0:+]; MID_RHS_MATCH_FROM(0.00)[]; FREEMAIL_ENVRCPT(0.00)[gmail.com]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; RCVD_TLS_ALL(0.00)[]; FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; RCVD_COUNT_TWO(0.00)[2]; TO_MATCH_ENVRCPT_ALL(0.00)[]; DBL_BLOCKED_OPENRESOLVER(0.00)[imap1.dmz-prg2.suse.org:rdns,imap1.dmz-prg2.suse.org:helo,suse.de:email,suse.de:dkim,suse.de:mid]; SPAMHAUS_XBL(0.00)[2a07:de40:b281:104:10:150:64:97:from]; DNSWL_BLOCKED(0.00)[2a07:de40:b281:106:10:150:64:167:received]; DKIM_TRACE(0.00)[suse.de:+] X-Spam-Flag: NO X-Spam-Score: -4.51 On 5/27/26 3:57 PM, Tristan Madani wrote: > From: Tristan Madani > > nft_tunnel_obj_destroy() calls metadata_dst_free() which directly > kfree()s the metadata_dst, ignoring the dst_entry refcount. Packets > that took a reference via dst_hold() in nft_tunnel_obj_eval() and > are still queued (e.g. in a netem qdisc) are left with a dangling > pointer. When these packets are eventually dequeued, dst_release() > operates on freed memory. > > Replace metadata_dst_free() with dst_release() so the metadata_dst > is freed only after all references are dropped. The dst subsystem > already handles metadata_dst cleanup in dst_destroy() when > DST_METADATA is set. > > Fixes: af308b94a2a4 ("netfilter: nf_tables: add tunnel support") > Cc: stable@vger.kernel.org > Signed-off-by: Tristan Madani Reviewed-by: Fernando Fernandez Mancera Thanks!