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 CBA38144D34; Tue, 23 Apr 2024 21:45:54 +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=1713908754; cv=none; b=X7iWOCyR3Sja2fkZclv/YM54mebZ3DL55J899yNHftEhL6ExdrrvUDo5e7iqQ5wvUQXgGkjlkeBt48OUJYiM6TvplCMnb4e0nz/CILrbwDSLBjKayf8Fp2sqMUlNV0SSw3wuNWkefjMZsAykZPnPUnymQY4Lel5U/JJ5s2a5gHc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713908754; c=relaxed/simple; bh=zIuKW2NyVfR90hraTHP40jwbIUx0WYIdoM/cpxo2S6k=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=SrlrW3oUbePAbvPZ/Q+Mzoi3tg3+jnGFE30Ch5B1UY6aaZ11gFavbm6Oc1pm07cM2eTUoX0FsgNblQ5V8v1GmFeix8OyDjbfVlS0T8qoxis3dabeKg5rr2I2LGypaI4e6o9sv52Yex+/MnExKur8aBmyl5wWD7IbHFmz9SWV2V4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=2hFuGCdJ; 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="2hFuGCdJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9D91FC116B1; Tue, 23 Apr 2024 21:45:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1713908754; bh=zIuKW2NyVfR90hraTHP40jwbIUx0WYIdoM/cpxo2S6k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=2hFuGCdJ/lYTwibgeptx6EH8Dk2mK5wHujT2gnnml1MXKyfkxb6sDsNClzyq5veum qDtpC30+izetz4x+zeBRnYp8YpwBMxXcYkjFfUeR7t7yxtCl7BRCJdgxbzqC3Qq1NN wn4Hxqu5jLgWRP1tODjo4119LsaKKY1p8R2G8vwk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Stable@vger.kernel.org, Qiang Zhang , "Masami Hiramatsu (Google)" Subject: [PATCH 6.1 131/141] bootconfig: use memblock_free_late to free xbc memory to buddy Date: Tue, 23 Apr 2024 14:39:59 -0700 Message-ID: <20240423213857.470510888@linuxfoundation.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240423213853.356988651@linuxfoundation.org> References: <20240423213853.356988651@linuxfoundation.org> User-Agent: quilt/0.67 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 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Qiang Zhang commit 89f9a1e876b5a7ad884918c03a46831af202c8a0 upstream. On the time to free xbc memory in xbc_exit(), memblock may has handed over memory to buddy allocator. So it doesn't make sense to free memory back to memblock. memblock_free() called by xbc_exit() even causes UAF bugs on architectures with CONFIG_ARCH_KEEP_MEMBLOCK disabled like x86. Following KASAN logs shows this case. This patch fixes the xbc memory free problem by calling memblock_free() in early xbc init error rewind path and calling memblock_free_late() in xbc exit path to free memory to buddy allocator. [ 9.410890] ================================================================== [ 9.418962] BUG: KASAN: use-after-free in memblock_isolate_range+0x12d/0x260 [ 9.426850] Read of size 8 at addr ffff88845dd30000 by task swapper/0/1 [ 9.435901] CPU: 9 PID: 1 Comm: swapper/0 Tainted: G U 6.9.0-rc3-00208-g586b5dfb51b9 #5 [ 9.446403] Hardware name: Intel Corporation RPLP LP5 (CPU:RaptorLake)/RPLP LP5 (ID:13), BIOS IRPPN02.01.01.00.00.19.015.D-00000000 Dec 28 2023 [ 9.460789] Call Trace: [ 9.463518] [ 9.465859] dump_stack_lvl+0x53/0x70 [ 9.469949] print_report+0xce/0x610 [ 9.473944] ? __virt_addr_valid+0xf5/0x1b0 [ 9.478619] ? memblock_isolate_range+0x12d/0x260 [ 9.483877] kasan_report+0xc6/0x100 [ 9.487870] ? memblock_isolate_range+0x12d/0x260 [ 9.493125] memblock_isolate_range+0x12d/0x260 [ 9.498187] memblock_phys_free+0xb4/0x160 [ 9.502762] ? __pfx_memblock_phys_free+0x10/0x10 [ 9.508021] ? mutex_unlock+0x7e/0xd0 [ 9.512111] ? __pfx_mutex_unlock+0x10/0x10 [ 9.516786] ? kernel_init_freeable+0x2d4/0x430 [ 9.521850] ? __pfx_kernel_init+0x10/0x10 [ 9.526426] xbc_exit+0x17/0x70 [ 9.529935] kernel_init+0x38/0x1e0 [ 9.533829] ? _raw_spin_unlock_irq+0xd/0x30 [ 9.538601] ret_from_fork+0x2c/0x50 [ 9.542596] ? __pfx_kernel_init+0x10/0x10 [ 9.547170] ret_from_fork_asm+0x1a/0x30 [ 9.551552] [ 9.555649] The buggy address belongs to the physical page: [ 9.561875] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x45dd30 [ 9.570821] flags: 0x200000000000000(node=0|zone=2) [ 9.576271] page_type: 0xffffffff() [ 9.580167] raw: 0200000000000000 ffffea0011774c48 ffffea0012ba1848 0000000000000000 [ 9.588823] raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000 [ 9.597476] page dumped because: kasan: bad access detected [ 9.605362] Memory state around the buggy address: [ 9.610714] ffff88845dd2ff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 9.618786] ffff88845dd2ff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 9.626857] >ffff88845dd30000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 9.634930] ^ [ 9.638534] ffff88845dd30080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 9.646605] ffff88845dd30100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 9.654675] ================================================================== Link: https://lore.kernel.org/all/20240414114944.1012359-1-qiang4.zhang@linux.intel.com/ Fixes: 40caa127f3c7 ("init: bootconfig: Remove all bootconfig data when the init memory is removed") Cc: Stable@vger.kernel.org Signed-off-by: Qiang Zhang Acked-by: Masami Hiramatsu (Google) Signed-off-by: Masami Hiramatsu (Google) Signed-off-by: Greg Kroah-Hartman --- include/linux/bootconfig.h | 7 ++++++- lib/bootconfig.c | 19 +++++++++++-------- 2 files changed, 17 insertions(+), 9 deletions(-) --- a/include/linux/bootconfig.h +++ b/include/linux/bootconfig.h @@ -287,7 +287,12 @@ int __init xbc_init(const char *buf, siz int __init xbc_get_info(int *node_size, size_t *data_size); /* XBC cleanup data structures */ -void __init xbc_exit(void); +void __init _xbc_exit(bool early); + +static inline void xbc_exit(void) +{ + _xbc_exit(false); +} /* XBC embedded bootconfig data in kernel */ #ifdef CONFIG_BOOT_CONFIG_EMBED --- a/lib/bootconfig.c +++ b/lib/bootconfig.c @@ -61,9 +61,12 @@ static inline void * __init xbc_alloc_me return memblock_alloc(size, SMP_CACHE_BYTES); } -static inline void __init xbc_free_mem(void *addr, size_t size) +static inline void __init xbc_free_mem(void *addr, size_t size, bool early) { - memblock_free(addr, size); + if (early) + memblock_free(addr, size); + else if (addr) + memblock_free_late(__pa(addr), size); } #else /* !__KERNEL__ */ @@ -73,7 +76,7 @@ static inline void *xbc_alloc_mem(size_t return malloc(size); } -static inline void xbc_free_mem(void *addr, size_t size) +static inline void xbc_free_mem(void *addr, size_t size, bool early) { free(addr); } @@ -904,13 +907,13 @@ static int __init xbc_parse_tree(void) * If you need to reuse xbc_init() with new boot config, you can * use this. */ -void __init xbc_exit(void) +void __init _xbc_exit(bool early) { - xbc_free_mem(xbc_data, xbc_data_size); + xbc_free_mem(xbc_data, xbc_data_size, early); xbc_data = NULL; xbc_data_size = 0; xbc_node_num = 0; - xbc_free_mem(xbc_nodes, sizeof(struct xbc_node) * XBC_NODE_MAX); + xbc_free_mem(xbc_nodes, sizeof(struct xbc_node) * XBC_NODE_MAX, early); xbc_nodes = NULL; brace_index = 0; } @@ -963,7 +966,7 @@ int __init xbc_init(const char *data, si if (!xbc_nodes) { if (emsg) *emsg = "Failed to allocate bootconfig nodes"; - xbc_exit(); + _xbc_exit(true); return -ENOMEM; } memset(xbc_nodes, 0, sizeof(struct xbc_node) * XBC_NODE_MAX); @@ -977,7 +980,7 @@ int __init xbc_init(const char *data, si *epos = xbc_err_pos; if (emsg) *emsg = xbc_err_msg; - xbc_exit(); + _xbc_exit(true); } else ret = xbc_node_num;