From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8002125228D for ; Thu, 4 Jun 2026 10:49:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780570154; cv=none; b=nO/QxcAYyoI6LdQuvAFkOri5vKCXZfgjc0sd9VMbAK5ejsraDoiSSlA3TOQ3nWwUozsxZg+YB2+kjjyFo+Swse0tpiMoo4vn5evhNHDerTE+57WAl9SuW9KU1h41OVz1J0ozu6tOmqCEFhQz0R5uKo5kNQ3rvAoZzAuINsf9YDw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780570154; c=relaxed/simple; bh=77KNrax/j1yu5JbX0Y7Hq56lfpAaYAfr8apFd9XaASk=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=rMRByh2aKFmhAk5VpB2EgLNGuKerzKJFiWanqGxoNMDc/ehrifrGXe+xAFIaY5iBjHF7NWVQ/pd5dPKQdO1CBd4fYOeUqJVY2cV+hY3VO5rLEeINVwpjEwzL3Nepo6bIy9J46vQg9HVjHcs4TgdAY4boDqvEKv9zxat4kMRVXGY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=N8avISLE; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="N8avISLE" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B5C5E1F00893; Thu, 4 Jun 2026 10:49:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1780570153; bh=Y3fMRFMFw0hhGJXzM4A2NwHE7SD2SglMjF6/AYL57H4=; h=Subject:To:Cc:From:Date; b=N8avISLEHVmfsX4Ku8xT+Do0AcFyZk22pkJNJJoMLXxfr3hCxVdY3hLe7yFKdOV+r 94+QC6ICd8TGtC2TzlJ8DLSCrMoE0ZEctWvfnsXLVY2yntb52YjYdeb13Emdq6s+Av uKS0az4r7ZYQA6Of/hfRWjvNAC7TelSTbVxZUOco= Subject: FAILED: patch "[PATCH] thunderbolt: property: Cap recursion depth in" failed to apply to 6.1-stable tree To: michael.bommarito@gmail.com,mika.westerberg@linux.intel.com Cc: From: Date: Thu, 04 Jun 2026 12:48:08 +0200 Message-ID: <2026060408-scoundrel-harmonica-f5da@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit The patch below does not apply to the 6.1-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y git checkout FETCH_HEAD git cherry-pick -x 928abe19fbf0127003abcb1ea69cabc1c897d0ab # git commit -s git send-email --to '' --in-reply-to '2026060408-scoundrel-harmonica-f5da@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 928abe19fbf0127003abcb1ea69cabc1c897d0ab Mon Sep 17 00:00:00 2001 From: Michael Bommarito Date: Sun, 10 May 2026 19:16:58 -0400 Subject: [PATCH] thunderbolt: property: Cap recursion depth in __tb_property_parse_dir() A DIRECTORY entry's value field is used as the dir_offset for a recursive call into __tb_property_parse_dir() with no depth counter. A crafted peer that chains DIRECTORY entries into a back-reference loop drives the parser until the kernel stack is exhausted and the guard page fires. Any untrusted XDomain peer (cable, dock, in-line inspector, adjacent host) that reaches the PROPERTIES_REQUEST control-plane exchange can trigger this without authentication. Thread a depth counter through tb_property_parse() and __tb_property_parse_dir(), and reject blocks that exceed TB_PROPERTY_MAX_DEPTH = 8. That is comfortably larger than any observed legitimate XDomain layout. Operators who do not need XDomain host-to-host discovery can disable the path entirely with thunderbolt.xdomain=0 on the kernel command line. Fixes: cdae7c07e3e3 ("thunderbolt: Add support for XDomain properties") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4-6 Assisted-by: Codex:gpt-5-4 Signed-off-by: Michael Bommarito Signed-off-by: Mika Westerberg diff --git a/drivers/thunderbolt/property.c b/drivers/thunderbolt/property.c index 74c92f9801ff..da2c59a17db5 100644 --- a/drivers/thunderbolt/property.c +++ b/drivers/thunderbolt/property.c @@ -35,10 +35,11 @@ struct tb_property_dir_entry { }; #define TB_PROPERTY_ROOTDIR_MAGIC 0x55584401 +#define TB_PROPERTY_MAX_DEPTH 8 static struct tb_property_dir *__tb_property_parse_dir(const u32 *block, size_t block_len, unsigned int dir_offset, size_t dir_len, - bool is_root); + bool is_root, unsigned int depth); static inline void parse_dwdata(void *dst, const void *src, size_t dwords) { @@ -97,7 +98,8 @@ tb_property_alloc(const char *key, enum tb_property_type type) } static struct tb_property *tb_property_parse(const u32 *block, size_t block_len, - const struct tb_property_entry *entry) + const struct tb_property_entry *entry, + unsigned int depth) { char key[TB_PROPERTY_KEY_SIZE + 1]; struct tb_property *property; @@ -118,7 +120,7 @@ static struct tb_property *tb_property_parse(const u32 *block, size_t block_len, switch (property->type) { case TB_PROPERTY_TYPE_DIRECTORY: dir = __tb_property_parse_dir(block, block_len, entry->value, - entry->length, false); + entry->length, false, depth + 1); if (!dir) { kfree(property); return NULL; @@ -163,13 +165,17 @@ static struct tb_property *tb_property_parse(const u32 *block, size_t block_len, } static struct tb_property_dir *__tb_property_parse_dir(const u32 *block, - size_t block_len, unsigned int dir_offset, size_t dir_len, bool is_root) + size_t block_len, unsigned int dir_offset, size_t dir_len, bool is_root, + unsigned int depth) { const struct tb_property_entry *entries; size_t i, content_len, nentries; unsigned int content_offset; struct tb_property_dir *dir; + if (depth > TB_PROPERTY_MAX_DEPTH) + return NULL; + dir = kzalloc_obj(*dir); if (!dir) return NULL; @@ -200,7 +206,7 @@ static struct tb_property_dir *__tb_property_parse_dir(const u32 *block, for (i = 0; i < nentries; i++) { struct tb_property *property; - property = tb_property_parse(block, block_len, &entries[i]); + property = tb_property_parse(block, block_len, &entries[i], depth); if (!property) { tb_property_free_dir(dir); return NULL; @@ -239,7 +245,7 @@ struct tb_property_dir *tb_property_parse_dir(const u32 *block, return NULL; return __tb_property_parse_dir(block, block_len, 0, rootdir->length, - true); + true, 0); } /**