Re: [PATCH] fs/squashfs: restrict length of xattr_ids in read_xattr_id_table

From: kernel test robot
Date: Wed Feb 03 2021 - 09:12:39 EST


Hi Sabyrzhan,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on linux/master]
[also build test WARNING on linus/master v5.11-rc6 next-20210125]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url: https://github.com/0day-ci/linux/commits/Sabyrzhan-Tasbolatov/fs-squashfs-restrict-length-of-xattr_ids-in-read_xattr_id_table/20210203-184131
base: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 2ab38c17aac10bf55ab3efde4c4db3893d8691d2
config: i386-randconfig-s001-20210202 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-15) 9.3.0
reproduce:
# apt-get install sparse
# sparse version: v0.6.3-215-g0fb77bb6-dirty
# https://github.com/0day-ci/linux/commit/7e2a858aa7b4de58aa7b037aad474710f07807e8
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Sabyrzhan-Tasbolatov/fs-squashfs-restrict-length-of-xattr_ids-in-read_xattr_id_table/20210203-184131
git checkout 7e2a858aa7b4de58aa7b037aad474710f07807e8
# save the attached .config to linux build tree
make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=i386

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@xxxxxxxxx>

All warnings (new ones prefixed by >>):

fs/squashfs/xattr_id.c: In function 'squashfs_read_xattr_id_table':
>> fs/squashfs/xattr_id.c:82:10: warning: returning 'int' from a function with return type '__le64 *' {aka 'long long unsigned int *'} makes pointer from integer without a cast [-Wint-conversion]
82 | return -ENOMEM;
| ^


"sparse warnings: (new ones prefixed by >>)"
>> fs/squashfs/xattr_id.c:82:24: sparse: sparse: incorrect type in return expression (different base types) @@ expected restricted __le64 [usertype] * @@ got int @@
fs/squashfs/xattr_id.c:82:24: sparse: expected restricted __le64 [usertype] *
fs/squashfs/xattr_id.c:82:24: sparse: got int

vim +82 fs/squashfs/xattr_id.c

48
49
50 /*
51 * Read uncompressed xattr id lookup table indexes from disk into memory
52 */
53 __le64 *squashfs_read_xattr_id_table(struct super_block *sb, u64 start,
54 u64 *xattr_table_start, int *xattr_ids)
55 {
56 unsigned int len;
57 struct squashfs_xattr_id_table *id_table;
58
59 id_table = squashfs_read_table(sb, start, sizeof(*id_table));
60 if (IS_ERR(id_table))
61 return (__le64 *) id_table;
62
63 *xattr_table_start = le64_to_cpu(id_table->xattr_table_start);
64 *xattr_ids = le32_to_cpu(id_table->xattr_ids);
65 kfree(id_table);
66
67 /* Sanity check values */
68
69 /* there is always at least one xattr id */
70 if (*xattr_ids == 0)
71 return ERR_PTR(-EINVAL);
72
73 /* xattr_table should be less than start */
74 if (*xattr_table_start >= start)
75 return ERR_PTR(-EINVAL);
76
77 len = SQUASHFS_XATTR_BLOCK_BYTES(*xattr_ids);
78
79 TRACE("In read_xattr_index_table, length %d\n", len);
80
81 if (len > KMALLOC_MAX_SIZE)
> 82 return -ENOMEM;

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx

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