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 D2E383594E; Tue, 12 Aug 2025 19:16:39 +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=1755026199; cv=none; b=FsUiB7NTQo4B6G5Ru8xiOEi0H0WOro0/CYveb9HtMbOJm7mrtXvV1uezlY297+2IxOAFbbCyVD4A6hmNP/D/Me+LFhkDxFzAHAH9PvfuUwdlL/AWEfOUS8XvhEV4OSyku2SwC2JTXc3S1C2QHSL7A9Nth8edcQeZhSDs39yIBbE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755026199; c=relaxed/simple; bh=18TZplVBfaWbPENfVQiG8RkmdgU1zuxHhvMMGwpq1x4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=jK2gUlkShl4hGr3swNEdiq0SPIvz4UeU97R9Bmr/MAjcbuUk96zbA8dOu0iV4ThVS8aTwun/A3kj8JR/fiKpilKxgMh9lWQsvAm+FlXYQY5YJDedqt37H/vlYPiS5oJlgZUCyOzBUBXXu9ryVPqXunuyEKIuu8kqyy2cIR7qD2E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=I8r+ODNa; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="I8r+ODNa" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 40A38C4CEF0; Tue, 12 Aug 2025 19:16:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1755026199; bh=18TZplVBfaWbPENfVQiG8RkmdgU1zuxHhvMMGwpq1x4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=I8r+ODNa4UFsbk2DmYMjICSRRjPYM/MjjwjvnFoYCmZK6g8hd0I5DSgmiH7O6zkpR ZzKKQJohFHu4HELnctHRaSDQ48/NV7G5MO+sqn06gUUHtYWX55wOxChTZRq5FA1aWt AM9CbfmhWqKGBwvJ+YrDNAgYLBGplrAP8wNTd+h0= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Alexey Kardashevskiy , Tom Lendacky , "Pratik R. Sampat" , Herbert Xu , Sasha Levin Subject: [PATCH 6.15 267/480] crypto: ccp - Fix locking on alloc failure handling Date: Tue, 12 Aug 2025 19:47:55 +0200 Message-ID: <20250812174408.455003443@linuxfoundation.org> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20250812174357.281828096@linuxfoundation.org> References: <20250812174357.281828096@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Alexey Kardashevskiy [ Upstream commit b4abeccb8d39db7d9b51cb0098d6458760b30a75 ] The __snp_alloc_firmware_pages() helper allocates pages in the firmware state (alloc + rmpupdate). In case of failed rmpupdate, it tries reclaiming pages with already changed state. This requires calling the PSP firmware and since there is sev_cmd_mutex to guard such calls, the helper takes a "locked" parameter so specify if the lock needs to be held. Most calls happen from snp_alloc_firmware_page() which executes without the lock. However commit 24512afa4336 ("crypto: ccp: Handle the legacy TMR allocation when SNP is enabled") switched sev_fw_alloc() from alloc_pages() (which does not call the PSP) to __snp_alloc_firmware_pages() (which does) but did not account for the fact that sev_fw_alloc() is called from __sev_platform_init_locked() (via __sev_platform_init_handle_tmr()) and executes with the lock held. Add a "locked" parameter to __snp_alloc_firmware_pages(). Make sev_fw_alloc() use the new parameter to prevent potential deadlock in rmp_mark_pages_firmware() if rmpupdate() failed. Fixes: 24512afa4336 ("crypto: ccp: Handle the legacy TMR allocation when SNP is enabled") Signed-off-by: Alexey Kardashevskiy Reviewed-by: Tom Lendacky Reviewed-by: Pratik R. Sampat Signed-off-by: Herbert Xu Signed-off-by: Sasha Levin --- drivers/crypto/ccp/sev-dev.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c index 2e87ca0e292a..4d790837af22 100644 --- a/drivers/crypto/ccp/sev-dev.c +++ b/drivers/crypto/ccp/sev-dev.c @@ -424,7 +424,7 @@ static int rmp_mark_pages_firmware(unsigned long paddr, unsigned int npages, boo return rc; } -static struct page *__snp_alloc_firmware_pages(gfp_t gfp_mask, int order) +static struct page *__snp_alloc_firmware_pages(gfp_t gfp_mask, int order, bool locked) { unsigned long npages = 1ul << order, paddr; struct sev_device *sev; @@ -443,7 +443,7 @@ static struct page *__snp_alloc_firmware_pages(gfp_t gfp_mask, int order) return page; paddr = __pa((unsigned long)page_address(page)); - if (rmp_mark_pages_firmware(paddr, npages, false)) + if (rmp_mark_pages_firmware(paddr, npages, locked)) return NULL; return page; @@ -453,7 +453,7 @@ void *snp_alloc_firmware_page(gfp_t gfp_mask) { struct page *page; - page = __snp_alloc_firmware_pages(gfp_mask, 0); + page = __snp_alloc_firmware_pages(gfp_mask, 0, false); return page ? page_address(page) : NULL; } @@ -488,7 +488,7 @@ static void *sev_fw_alloc(unsigned long len) { struct page *page; - page = __snp_alloc_firmware_pages(GFP_KERNEL, get_order(len)); + page = __snp_alloc_firmware_pages(GFP_KERNEL, get_order(len), true); if (!page) return NULL; -- 2.39.5