linux-kernel - Re: [PATCH 2/2] thp, shmem: Fix conflict of above-47bit hint address and PMD alignment

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:   Sat, 28 Dec 2019 08:10:07 +0800
From:   kbuild test robot <lkp@...el.com>
To:     "Kirill A. Shutemov" <kirill@...temov.name>
Cc:     kbuild-all@...ts.01.org, Andrew Morton <akpm@...ux-foundation.org>,
        "Willhalm, Thomas" <thomas.willhalm@...el.com>,
        Dan Williams <dan.j.williams@...el.com>,
        "Bruggeman, Otto G" <otto.g.bruggeman@...el.com>,
        "Aneesh Kumar K . V" <aneesh.kumar@...ux.vnet.ibm.com>,
        linux-mm@...ck.org, x86@...nel.org, linux-kernel@...r.kernel.org,
        "Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>
Subject: Re: [PATCH 2/2] thp, shmem: Fix conflict of above-47bit hint address
 and PMD alignment

Hi "Kirill,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on linus/master]
[also build test WARNING on v5.5-rc3 next-20191220]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]

url:    https://github.com/0day-ci/linux/commits/Kirill-A-Shutemov/Fix-two-above-47bit-hint-address-vs-THP-bugs/20191223-221713
base:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 46cf053efec6a3a5f343fead837777efe8252a46
reproduce:
        # apt-get install sparse
        # sparse version: v0.6.1-129-g341daf20-dirty
        make ARCH=x86_64 allmodconfig
        make C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__'

If you fix the issue, kindly add following tag
Reported-by: kbuild test robot <lkp@...el.com>


sparse warnings: (new ones prefixed by >>)

>> mm/shmem.c:2147:34: sparse: sparse: incorrect type in argument 1 (different base types)
>> mm/shmem.c:2147:34: sparse:    expected struct file *
>> mm/shmem.c:2147:34: sparse:    got unsigned long uaddr

vim +2147 mm/shmem.c

  2073	
  2074	unsigned long shmem_get_unmapped_area(struct file *file,
  2075					      unsigned long uaddr, unsigned long len,
  2076					      unsigned long pgoff, unsigned long flags)
  2077	{
  2078		unsigned long (*get_area)(struct file *,
  2079			unsigned long, unsigned long, unsigned long, unsigned long);
  2080		unsigned long addr;
  2081		unsigned long offset;
  2082		unsigned long inflated_len;
  2083		unsigned long inflated_addr;
  2084		unsigned long inflated_offset;
  2085	
  2086		if (len > TASK_SIZE)
  2087			return -ENOMEM;
  2088	
  2089		get_area = current->mm->get_unmapped_area;
  2090		addr = get_area(file, uaddr, len, pgoff, flags);
  2091	
  2092		if (!IS_ENABLED(CONFIG_TRANSPARENT_HUGE_PAGECACHE))
  2093			return addr;
  2094		if (IS_ERR_VALUE(addr))
  2095			return addr;
  2096		if (addr & ~PAGE_MASK)
  2097			return addr;
  2098		if (addr > TASK_SIZE - len)
  2099			return addr;
  2100	
  2101		if (shmem_huge == SHMEM_HUGE_DENY)
  2102			return addr;
  2103		if (len < HPAGE_PMD_SIZE)
  2104			return addr;
  2105		if (flags & MAP_FIXED)
  2106			return addr;
  2107		/*
  2108		 * Our priority is to support MAP_SHARED mapped hugely;
  2109		 * and support MAP_PRIVATE mapped hugely too, until it is COWed.
  2110		 * But if caller specified an address hint and we allocated area there
  2111		 * successfully, respect that as before.
  2112		 */
  2113		if (uaddr == addr)
  2114			return addr;
  2115	
  2116		if (shmem_huge != SHMEM_HUGE_FORCE) {
  2117			struct super_block *sb;
  2118	
  2119			if (file) {
  2120				VM_BUG_ON(file->f_op != &shmem_file_operations);
  2121				sb = file_inode(file)->i_sb;
  2122			} else {
  2123				/*
  2124				 * Called directly from mm/mmap.c, or drivers/char/mem.c
  2125				 * for "/dev/zero", to create a shared anonymous object.
  2126				 */
  2127				if (IS_ERR(shm_mnt))
  2128					return addr;
  2129				sb = shm_mnt->mnt_sb;
  2130			}
  2131			if (SHMEM_SB(sb)->huge == SHMEM_HUGE_NEVER)
  2132				return addr;
  2133		}
  2134	
  2135		offset = (pgoff << PAGE_SHIFT) & (HPAGE_PMD_SIZE-1);
  2136		if (offset && offset + len < 2 * HPAGE_PMD_SIZE)
  2137			return addr;
  2138		if ((addr & (HPAGE_PMD_SIZE-1)) == offset)
  2139			return addr;
  2140	
  2141		inflated_len = len + HPAGE_PMD_SIZE - PAGE_SIZE;
  2142		if (inflated_len > TASK_SIZE)
  2143			return addr;
  2144		if (inflated_len < len)
  2145			return addr;
  2146	
> 2147		inflated_addr = get_area(uaddr, 0, inflated_len, 0, flags);
  2148		if (IS_ERR_VALUE(inflated_addr))
  2149			return addr;
  2150		if (inflated_addr & ~PAGE_MASK)
  2151			return addr;
  2152	
  2153		inflated_offset = inflated_addr & (HPAGE_PMD_SIZE-1);
  2154		inflated_addr += offset - inflated_offset;
  2155		if (inflated_offset > offset)
  2156			inflated_addr += HPAGE_PMD_SIZE;
  2157	
  2158		if (inflated_addr > TASK_SIZE - len)
  2159			return addr;
  2160		return inflated_addr;
  2161	}
  2162	

---
0-DAY kernel test infrastructure                 Open Source Technology Center
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org Intel Corporation