From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 EEBB427E7C1; Wed, 4 Jun 2025 01:07:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748999256; cv=none; b=gwupNY6x07VORfoi39VSeOHrxtzrnh8DqCkUzLnt2lVg3BdoTGwZVR9Rev1Ne+EC/ECV5OGYJp+4T3YKWW7weS3KL/gCBWQQJ5cFnq2h0cvJdl1YyU5nckmg2vD9fIclWABcptoB4d2EWZ1NwnANQCZByDhnWm+skB0xVs0lcIs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748999256; c=relaxed/simple; bh=gTFSugQZq0CA78LB8DIcC566oQZIVSl8nUIclIB1qfo=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=rF9bcs+XAzjrFpU5Dqg2r8OPrC/3v+gOeRxKaeQP1LkIBLuT8+hwh9DbCzs3KTB4Qr/M2DO8YNVu8tvvx+iaqprDKT6tYZavemPfXsbgu8g+bUxpdAa66F/B5eBV9k8kMLnmyCKegKmhLDH5MT949gsYXTPfXaqFqUywWxn5n3M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=G3UGNDRg; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="G3UGNDRg" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CDF78C4CEED; Wed, 4 Jun 2025 01:07:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1748999255; bh=gTFSugQZq0CA78LB8DIcC566oQZIVSl8nUIclIB1qfo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=G3UGNDRgn61UBbG9m2uC4OjOTo3NRl87staGc8m8b9oTJnbzpw3nupDrbOu5oeHdK mjR3z5sKS1NSdVC43fyHUKI1Hjj9rfs+saklm5IfprhhEecNlUshdN+r+PkUkv3GsE UfagtDtZMlSsd37djG+gZHVz27dJpNu4ZVlubw65PGOIXWIfgb6b0rEYDkTe7F8VQb zxzg+Pzyk9/AakHT3fxlezgiV8eTeUiItv8G1oNp+kKlXHoO4lAyigW7TShhowbpF7 yJzvEV1X6f+/5a5LI5JV3Ztu3Qqos6qWr/suGAAT0q9uLu6wEWB81vZX3hs4rSAkqD wrSMUY4aEsyEg== From: Sasha Levin To: patches@lists.linux.dev, stable@vger.kernel.org Cc: Daniel Wagner , Justin Tee , "Martin K . Petersen" , Sasha Levin , james.smart@broadcom.com, dick.kennedy@broadcom.com, linux-scsi@vger.kernel.org Subject: [PATCH AUTOSEL 5.4 18/20] scsi: lpfc: Use memcpy() for BIOS version Date: Tue, 3 Jun 2025 21:07:04 -0400 Message-Id: <20250604010706.7395-18-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250604010706.7395-1-sashal@kernel.org> References: <20250604010706.7395-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 5.4.293 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Daniel Wagner [ Upstream commit ae82eaf4aeea060bb736c3e20c0568b67c701d7d ] The strlcat() with FORTIFY support is triggering a panic because it thinks the target buffer will overflow although the correct target buffer size is passed in. Anyway, instead of memset() with 0 followed by a strlcat(), just use memcpy() and ensure that the resulting buffer is NULL terminated. BIOSVersion is only used for the lpfc_printf_log() which expects a properly terminated string. Signed-off-by: Daniel Wagner Link: https://lore.kernel.org/r/20250409-fix-lpfc-bios-str-v1-1-05dac9e51e13@kernel.org Reviewed-by: Justin Tee Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin --- Let me understand the actual problem by examining the function more carefully. Based on the commit message, this is about a FORTIFY panic when using strlcat(): **YES** This commit should be backported to stable kernel trees. Here's my extensive analysis: ## Bug Analysis **Root Cause:** The commit fixes a kernel panic triggered by FORTIFY_SOURCE when using `strlcat()`. The FORTIFY infrastructure incorrectly detected a potential buffer overflow in the BIOS version string handling code. **The Problem Code:** ```c memset(phba->BIOSVersion, 0, sizeof(phba->BIOSVersion)); strlcat(phba->BIOSVersion, (char *)cntl_attr->bios_ver_str, sizeof(phba->BIOSVersion)); ``` **The Fix:** ```c memcpy(phba->BIOSVersion, cntl_attr->bios_ver_str, sizeof(phba->BIOSVersion)); phba->BIOSVersion[sizeof(phba->BIOSVersion) - 1] = '\0'; ``` ## Technical Details 1. **Buffer Sizes:** `BIOSVersion` is a 16-byte character array (`char BIOSVersion[16]` in lpfc.h:1267), while `bios_ver_str` is a 32-byte array (`uint32_t bios_ver_str[8]` in lpfc_hw4.h:3798). 2. **FORTIFY Issue:** The `strlcat()` function with FORTIFY enabled was triggering a false positive, causing kernel panics when it incorrectly calculated potential overflow conditions. 3. **Safe Solution:** The fix uses `memcpy()` for the exact buffer size and explicitly null-terminates the string, which is simpler and avoids the FORTIFY false positive. ## Backport Criteria Analysis ✅ **Fixes Important Bug:** This resolves kernel panics in production systems with FORTIFY enabled ✅ **Small & Contained:** Only 3 lines changed in a single function ✅ **Minimal Risk:** The change is functionally equivalent but safer ✅ **No Architectural Changes:** Simple string handling improvement ✅ **Clear Side Effects:** No behavioral changes beyond fixing the panic ✅ **Critical Subsystem:** SCSI driver stability is important for storage ## Comparison with Similar Commits This closely resembles **Similar Commit #2** (marked YES for backport) which fixed an overflow build issue with FORTIFY. Both commits: - Address FORTIFY- related compilation/runtime issues - Make minimal, safe code changes - Fix real problems affecting users - Have low regression risk ## Risk Assessment **Low Risk:** The change maintains identical functionality while eliminating the false positive. Both code paths copy BIOS version data into a 16-byte buffer and ensure null termination. The `memcpy()` approach is actually more predictable than `strlcat()` with an empty target buffer. ## Conclusion This commit fixes a real kernel panic issue that affects users running kernels with FORTIFY_SOURCE enabled. The fix is minimal, safe, and follows stable tree guidelines perfectly. It should definitely be backported to prevent production systems from experiencing these panics. drivers/scsi/lpfc/lpfc_sli.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/lpfc/lpfc_sli.c b/drivers/scsi/lpfc/lpfc_sli.c index 04b9a94f2f5e5..e1ef28d9a89e9 100644 --- a/drivers/scsi/lpfc/lpfc_sli.c +++ b/drivers/scsi/lpfc/lpfc_sli.c @@ -5407,9 +5407,9 @@ lpfc_sli4_get_ctl_attr(struct lpfc_hba *phba) phba->sli4_hba.lnk_info.lnk_no = bf_get(lpfc_cntl_attr_lnk_numb, cntl_attr); - memset(phba->BIOSVersion, 0, sizeof(phba->BIOSVersion)); - strlcat(phba->BIOSVersion, (char *)cntl_attr->bios_ver_str, + memcpy(phba->BIOSVersion, cntl_attr->bios_ver_str, sizeof(phba->BIOSVersion)); + phba->BIOSVersion[sizeof(phba->BIOSVersion) - 1] = '\0'; lpfc_printf_log(phba, KERN_INFO, LOG_SLI, "3086 lnk_type:%d, lnk_numb:%d, bios_ver:%s\n", -- 2.39.5