From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793207614; b=Ugai00kG4vaOseg8TLiR1OzJOiGUT+BXEW5gB7Owrt4nUw9sbJ08H5PDIUTQsDdCA90i ePGknq56fn9nP4+B2JZLEeZkd4scJ1tPdhBJNlAQA4F2RuDp96Vgp20Kau98BZ5rf5/Fg 4e1cP2gc3rkLtTWwHl7CxUExUtHh+eL/TKRZKwIl4qjgHxomiwEB7R6neMvMRT0h7MO8G lE+VaI5WruQyupb8LLMMB7PRzFaA1BUGPbJ9QqvDEgFvjvWm3Nn4Ywqz2Xnozgfg4CI7M 5TQEoPNImfWHyK89CJiCBVbGhx4JJ99qTS57CfDdQvwq8OygLg1qOJ1z2yJ+K9fU7/g== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793207614; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=LuqqY9efg7Zahvz+N72jxNkYg79ACIlpXhZycaYgTnU=; b=w1GUIk8bZTuzDsa9NuZWDoXcmimdyVqMdXZEPpuzGPwhP+rm3uc2k2tFJ5vPZDNwEHld 3kBeN2BFAN5SP9baBh56Bzn2bW/Or9jEqIrXS9Ctcpw/ssZby/wKcHWBjmehVb4FNy61T Katxbtm+8ohKDXd/RzlRI+/0ZFXyoq5a0r0cvNNo4DhHvMHLuLkCGnJxeWoFxGA19IRf1 rqv+2hlifWeysOipToROTQFdIbl9ovTsNQ6R31sWsOm5MibWZCppY9VQ6CEY3/qvB5DXR KyE+cdKCHCXXptIQJDnMgzf1eGUnov2wH3ZyGFJ1F3Ce8HDNnWLgoT2wExO6rfcu1Aw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=dfkIg6ak; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B5720606A327; Wed, 28 Oct 2026 17:13:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=dfkIg6ak Received: by smtp.kernel.org (Postfix) with ESMTPSA id 138B01F01829; Wed, 28 Oct 2026 17:13:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793207613; bh=LuqqY9efg7Zahvz+N72jxNkYg79ACIlpXhZycaYgTnU=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=dfkIg6akI05l8w9bzFlNv+5ojtvuya0jKg+BnX70HNT3aUYHGlTLvSE1F475ZhLJC 1+duPcdePl/eXD9jMRamH/KchuB0NkbbYDBiV/WzHwJtQGj5XV/XVy9rwHK5ePyHS3 vWcsRSZtFyHwe9KPbkAcIp7JViOtaxpz8AXNL7rs= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Lee Jones , "Masami Hiramatsu (Google)" , Steven Rostedt Subject: [PATCH 6.12 076/247] tracing/histograms: Reject non-stacktrace fields for synthetic stacktrace fields Date: Wed, 28 Oct 2026 17:57:59 +0100 Message-ID: <20261028165949.192125722@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261028165947.349197979@linuxfoundation.org> References: <20261028165947.349197979@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Lee Jones commit a244c241593b5b38a08f0df2cb43c26574efbdcb upstream. In check_synth_field(), when a synthetic event field is a stacktrace (field->is_stack) and the histogram field is not a "long[" stacktrace array, validation falls through to the generic size and signedness comparison. Because parse_synth_field() sets a stacktrace field's type to "__data_loc unsigned long[]", its size is sizeof(u64) and synth_field_signed() marks it as signed. Consequently, any 8-byte signed scalar histogram field passes the fallback check, and its scalar value is subsequently dereferenced as a kernel stacktrace pointer in get_field_size() and trace_stack(). Furthermore, checking strstr(hist_field->type, "long[") is insufficient because tracepoint fields defined with __bitmask() or __rel_bitmask() also have type "__data_loc unsigned long[]" or "__rel_loc unsigned long[]", whilst create_hist_field() treats them as 4-byte scalar values without HIST_FIELD_FL_STACKTRACE. Propagate HIST_FIELD_FL_STACKTRACE to variable references and field variables (whilst excluding variable aliases from per-element stacktrace capture), and reject any mismatch between HIST_FIELD_FL_STACKTRACE and field->is_stack in check_synth_field(). Cc: stable@vger.kernel.org Fixes: 00cf3d672a9d ("tracing: Allow synthetic events to pass around stacktraces") Link: https://patch.msgid.link/20261013112449.1006088-1-lee@kernel.org Signed-off-by: Lee Jones Acked-by: Masami Hiramatsu (Google) Signed-off-by: Steven Rostedt Signed-off-by: Greg Kroah-Hartman --- kernel/trace/trace_events_hist.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -2098,7 +2098,8 @@ static int init_var_ref(struct hist_fiel ref_field->size = var_field->size; ref_field->is_signed = var_field->is_signed; ref_field->flags |= var_field->flags & - (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); + (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS | + HIST_FIELD_FL_STACKTRACE); if (system) { ref_field->system = kstrdup(system, GFP_KERNEL); @@ -3286,6 +3287,7 @@ static struct field_var *create_field_va ret = -ENOMEM; goto err; } + var->flags |= val->flags & HIST_FIELD_FL_STACKTRACE; field_var->var = var; field_var->val = val; @@ -3904,7 +3906,10 @@ static int check_synth_field(struct synt && field->is_dynamic) return 0; - if (strstr(hist_field->type, "long[") && field->is_stack) + if (!!(hist_field->flags & HIST_FIELD_FL_STACKTRACE) != field->is_stack) + return -EINVAL; + + if (field->is_stack) return 0; if (strcmp(field->type, hist_field->type) != 0) { @@ -4443,7 +4448,8 @@ static int create_var_field(struct hist_ if (!ret && hist_data->fields[val_idx]->flags & HIST_FIELD_FL_EXECNAME) update_var_execname(hist_data->fields[val_idx]); - if (!ret && hist_data->fields[val_idx]->flags & + if (!ret && !(hist_data->fields[val_idx]->flags & HIST_FIELD_FL_ALIAS) && + hist_data->fields[val_idx]->flags & (HIST_FIELD_FL_STRING | HIST_FIELD_FL_STACKTRACE)) hist_data->fields[val_idx]->var_str_idx = hist_data->n_var_str++; @@ -5184,7 +5190,8 @@ static void hist_trigger_elt_update(stru if (hist_field->flags & HIST_FIELD_FL_VAR) { var_idx = hist_field->var.idx; - if (hist_field->flags & + if (!(hist_field->flags & HIST_FIELD_FL_ALIAS) && + hist_field->flags & (HIST_FIELD_FL_STRING | HIST_FIELD_FL_STACKTRACE)) { unsigned int str_start, var_str_idx, idx; char *str, *val_str;