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 06B1E4219F7; Tue, 7 Jul 2026 13:46:22 +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=1783431987; cv=none; b=ayOnG8c0QTU6YW6rxCOSyz8TT2DB/FFSr0JNArG/RQR1WybInWX5yWpXni1nsUDOaKRaul/nmNWEdGp3PEX816tJ8yUlwZrUfmJirFMRymDyZxkPKs1e59Ql6jUO5Uuc8cVyREBZNy4257bvRE6hN4iQ/KGFO1nmnVh889ahyf8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783431987; c=relaxed/simple; bh=W9H2l+XTH59Ig783jGszyEzxeqejZYk96tBBTaP0jt4=; h=Message-ID:Date:From:To:Cc:Subject:References:MIME-Version: Content-Type; b=pQ92xnbi8THATWPWdaXy4FuzetaVXONSXo8XLRzngtumVBBePimyt6lCxwgHjQXg2X8tuK/kmdzvp8efuKxg8gLBp7Jez3NSyQ7xL5c+W12M9Q6EU0rW51CiTwVObaQ4jwhOMbd/zYMmkdSlMTYT10iatih5M994uzUnRMyeQpk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=aq0pZmgn; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="aq0pZmgn" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DCB2A1F01559; Tue, 7 Jul 2026 13:46:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1783431981; bh=Y7Tm4/VM2bLRCHDwXtpN/zJB4V7HAUOrArAtD+vl6AA=; h=Date:From:To:Cc:Subject:References; b=aq0pZmgni4C6flCe7ODGZa4qt2Yc15mrD1taUd74RaIy3L2O0bMC1j6hEbA41TfA4 DT9fVoeo+2CbaF1wX0NkvFw8QgGoKlYdwNJH2Y68gFdnrxO2gAmXVA85ufOS7IK0ow jEpV4nuLRh1j64IEjzRZWT/kCReMAWT/PhSWBJMlxX83zqwJBf9YAyenIotFZOY4gQ oyMQ3N9Yuz/KDLnXKNLJPihmOZlZyM5ze4APdB7/RYRHMSCfd3TPLvrknGJmoMS8OT ZhKlZq0V0MPVdt8sK4o/O7u8/sUcZyBBvtSXnA94jm0nkoCIy6BT0RQJKb9AWog1ba mcVR22XfBYnDg== Received: from rostedt by gandalf with local (Exim 4.99.4) (envelope-from ) id 1wh681-00000000h64-0i7i; Tue, 07 Jul 2026 09:46:25 -0400 Message-ID: <20260707134625.010455998@kernel.org> User-Agent: quilt/0.69 Date: Tue, 07 Jul 2026 09:46:15 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Masami Hiramatsu , Mark Rutland , Mathieu Desnoyers , Andrew Morton , stable@vger.kernel.org, Peter Wang , Bart Van Assche Subject: [for-linus][PATCH 11/13] ufs: core: tracing: Do not dereference pointers in TP_printk() References: <20260707134604.275787924@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 From: Steven Rostedt The trace events in drivers/ufs/core/ufs_trace.h were converted to take a pointer to the hba structure as an argument for the tracepoint and then in TP_printk() the printing of the dev_name from the ring buffer was converted to using the dev dereferenced pointer from the hba saved pointer. This is not allowed as the TP_printk() is executed at the time the trace event is read from /sys/kernel/tracing/trace file. That can happen literally, seconds, minutes, hours, weeks, days, or even months later! There is no guarantee that the hba pointer will still exist by the time it is dereferenced when the "trace" file is read. Instead, save the device name from the hba pointer at the time the tracepoint is called and place it into the ring buffer event. Then the TP_printk() can read the name directly from the ring buffer and remove the possibility that it will read a freed pointer and crash the kernel. This was detected when testing the trace event code that looks for TP_printk() parameters doing illegal derferences[1] [1] https://lore.kernel.org/all/20260630184836.74d477b6@gandalf.local.home/ Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260630185412.283c26c5@gandalf.local.home Fixes: 583e518e71003 ("scsi: ufs: core: Add hba parameter to trace events") Reviewed-by: Peter Wang Reviewed-by: Bart Van Assche Signed-off-by: Steven Rostedt --- drivers/ufs/core/ufs_trace.h | 36 +++++++++++++++++++++++++++--------- 1 file changed, 27 insertions(+), 9 deletions(-) diff --git a/drivers/ufs/core/ufs_trace.h b/drivers/ufs/core/ufs_trace.h index 309ae51b4906..377a3c54b9f5 100644 --- a/drivers/ufs/core/ufs_trace.h +++ b/drivers/ufs/core/ufs_trace.h @@ -89,16 +89,18 @@ TRACE_EVENT(ufshcd_clk_gating, TP_STRUCT__entry( __field(struct ufs_hba *, hba) + __string(dev_name, dev_name(hba->dev)) __field(int, state) ), TP_fast_assign( + __assign_str(dev_name); __entry->hba = hba; __entry->state = state; ), TP_printk("%s: gating state changed to %s", - dev_name(__entry->hba->dev), + __get_str(dev_name), __print_symbolic(__entry->state, UFSCHD_CLK_GATING_STATES)) ); @@ -111,6 +113,7 @@ TRACE_EVENT(ufshcd_clk_scaling, TP_STRUCT__entry( __field(struct ufs_hba *, hba) + __string(dev_name, dev_name(hba->dev)) __string(state, state) __string(clk, clk) __field(u32, prev_state) @@ -119,6 +122,7 @@ TRACE_EVENT(ufshcd_clk_scaling, TP_fast_assign( __entry->hba = hba; + __assign_str(dev_name); __assign_str(state); __assign_str(clk); __entry->prev_state = prev_state; @@ -126,7 +130,7 @@ TRACE_EVENT(ufshcd_clk_scaling, ), TP_printk("%s: %s %s from %u to %u Hz", - dev_name(__entry->hba->dev), __get_str(state), __get_str(clk), + __get_str(dev_name), __get_str(state), __get_str(clk), __entry->prev_state, __entry->curr_state) ); @@ -138,16 +142,18 @@ TRACE_EVENT(ufshcd_auto_bkops_state, TP_STRUCT__entry( __field(struct ufs_hba *, hba) + __string(dev_name, dev_name(hba->dev)) __string(state, state) ), TP_fast_assign( __entry->hba = hba; + __assign_str(dev_name); __assign_str(state); ), TP_printk("%s: auto bkops - %s", - dev_name(__entry->hba->dev), __get_str(state)) + __get_str(dev_name), __get_str(state)) ); DECLARE_EVENT_CLASS(ufshcd_profiling_template, @@ -158,6 +164,7 @@ DECLARE_EVENT_CLASS(ufshcd_profiling_template, TP_STRUCT__entry( __field(struct ufs_hba *, hba) + __string(dev_name, dev_name(hba->dev)) __string(profile_info, profile_info) __field(s64, time_us) __field(int, err) @@ -165,13 +172,14 @@ DECLARE_EVENT_CLASS(ufshcd_profiling_template, TP_fast_assign( __entry->hba = hba; + __assign_str(dev_name); __assign_str(profile_info); __entry->time_us = time_us; __entry->err = err; ), TP_printk("%s: %s: took %lld usecs, err %d", - dev_name(__entry->hba->dev), __get_str(profile_info), + __get_str(dev_name), __get_str(profile_info), __entry->time_us, __entry->err) ); @@ -200,6 +208,7 @@ DECLARE_EVENT_CLASS(ufshcd_template, __field(s64, usecs) __field(int, err) __field(struct ufs_hba *, hba) + __string(dev_name, dev_name(hba->dev)) __field(int, dev_state) __field(int, link_state) ), @@ -208,13 +217,14 @@ DECLARE_EVENT_CLASS(ufshcd_template, __entry->usecs = usecs; __entry->err = err; __entry->hba = hba; + __assign_str(dev_name); __entry->dev_state = dev_state; __entry->link_state = link_state; ), TP_printk( "%s: took %lld usecs, dev_state: %s, link_state: %s, err %d", - dev_name(__entry->hba->dev), + __get_str(dev_name), __entry->usecs, __print_symbolic(__entry->dev_state, UFS_PWR_MODES), __print_symbolic(__entry->link_state, UFS_LINK_STATES), @@ -279,6 +289,7 @@ TRACE_EVENT(ufshcd_command, TP_STRUCT__entry( __field(struct scsi_device *, sdev) __field(struct ufs_hba *, hba) + __string(dev_name, dev_name(&sdev->sdev_dev)) __field(enum ufs_trace_str_t, str_t) __field(unsigned int, tag) __field(u32, doorbell) @@ -291,6 +302,7 @@ TRACE_EVENT(ufshcd_command, ), TP_fast_assign( + __assign_str(dev_name); __entry->sdev = sdev; __entry->hba = hba; __entry->str_t = str_t; @@ -307,7 +319,7 @@ TRACE_EVENT(ufshcd_command, TP_printk( "%s: %s: tag: %u, DB: 0x%x, size: %d, IS: %u, LBA: %llu, opcode: 0x%x (%s), group_id: 0x%x, hwq_id: %d", show_ufs_cmd_trace_str(__entry->str_t), - dev_name(&__entry->sdev->sdev_dev), __entry->tag, + __get_str(dev_name), __entry->tag, __entry->doorbell, __entry->transfer_len, __entry->intr, __entry->lba, (u32)__entry->opcode, str_opcode(__entry->opcode), (u32)__entry->group_id, __entry->hwq_id @@ -322,6 +334,7 @@ TRACE_EVENT(ufshcd_uic_command, TP_STRUCT__entry( __field(struct ufs_hba *, hba) + __string(dev_name, dev_name(hba->dev)) __field(enum ufs_trace_str_t, str_t) __field(u32, cmd) __field(u32, arg1) @@ -331,6 +344,7 @@ TRACE_EVENT(ufshcd_uic_command, TP_fast_assign( __entry->hba = hba; + __assign_str(dev_name); __entry->str_t = str_t; __entry->cmd = cmd; __entry->arg1 = arg1; @@ -340,7 +354,7 @@ TRACE_EVENT(ufshcd_uic_command, TP_printk( "%s: %s: cmd: 0x%x, arg1: 0x%x, arg2: 0x%x, arg3: 0x%x", - show_ufs_cmd_trace_str(__entry->str_t), dev_name(__entry->hba->dev), + show_ufs_cmd_trace_str(__entry->str_t), __get_str(dev_name), __entry->cmd, __entry->arg1, __entry->arg2, __entry->arg3 ) ); @@ -353,6 +367,7 @@ TRACE_EVENT(ufshcd_upiu, TP_STRUCT__entry( __field(struct ufs_hba *, hba) + __string(dev_name, dev_name(hba->dev)) __field(enum ufs_trace_str_t, str_t) __array(unsigned char, hdr, 12) __array(unsigned char, tsf, 16) @@ -361,6 +376,7 @@ TRACE_EVENT(ufshcd_upiu, TP_fast_assign( __entry->hba = hba; + __assign_str(dev_name); __entry->str_t = str_t; memcpy(__entry->hdr, hdr, sizeof(__entry->hdr)); memcpy(__entry->tsf, tsf, sizeof(__entry->tsf)); @@ -369,7 +385,7 @@ TRACE_EVENT(ufshcd_upiu, TP_printk( "%s: %s: HDR:%s, %s:%s", - show_ufs_cmd_trace_str(__entry->str_t), dev_name(__entry->hba->dev), + show_ufs_cmd_trace_str(__entry->str_t), __get_str(dev_name), __print_hex(__entry->hdr, sizeof(__entry->hdr)), show_ufs_cmd_trace_tsf(__entry->tsf_t), __print_hex(__entry->tsf, sizeof(__entry->tsf)) @@ -384,16 +400,18 @@ TRACE_EVENT(ufshcd_exception_event, TP_STRUCT__entry( __field(struct ufs_hba *, hba) + __string(dev_name, dev_name(hba->dev)) __field(u16, status) ), TP_fast_assign( __entry->hba = hba; + __assign_str(dev_name); __entry->status = status; ), TP_printk("%s: status 0x%x", - dev_name(__entry->hba->dev), __entry->status + __get_str(dev_name), __entry->status ) ); -- 2.53.0