net/switchdev/switchdev.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
From: "Minghao Chi (CGEL ZTE)" <chi.minghao@zte.com.cn>
Replace zero-length array with flexible-array member and make use
of the struct_size() helper in kmalloc(). For example:
struct switchdev_deferred_item {
...
unsigned long data[];
};
Make use of the struct_size() helper instead of an open-coded version
in order to avoid any potential type mistakes.
Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Minghao Chi (CGEL ZTE) <chi.minghao@zte.com.cn>
---
net/switchdev/switchdev.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/switchdev/switchdev.c b/net/switchdev/switchdev.c
index b62565278fac..b3aedd0ef4d0 100644
--- a/net/switchdev/switchdev.c
+++ b/net/switchdev/switchdev.c
@@ -85,7 +85,7 @@ static int switchdev_deferred_enqueue(struct net_device *dev,
{
struct switchdev_deferred_item *dfitem;
- dfitem = kmalloc(sizeof(*dfitem) + data_len, GFP_ATOMIC);
+ dfitem = kmalloc(struct_size(*dfitem, data, data_len), GFP_ATOMIC);
if (!dfitem)
return -ENOMEM;
dfitem->dev = dev;
--
2.25.1
Hi,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on linus/master]
[also build test ERROR on v5.17-rc1 next-20220128]
[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/cgel-zte-gmail-com/net-switchdev-use-struct_size-over-open-coded-arithmetic/20220128-155848
base: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 23a46422c56144939c091c76cf389aa863ce9c18
config: arm-orion5x_defconfig (https://download.01.org/0day-ci/archive/20220128/202201282035.8dNEcULs-lkp@intel.com/config)
compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 33b45ee44b1f32ffdbc995e6fec806271b4b3ba4)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# install arm cross compiling tool for clang build
# apt-get install binutils-arm-linux-gnueabi
# https://github.com/0day-ci/linux/commit/bf0e33a8c3deb700b95173a37dd16754341ba70e
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review cgel-zte-gmail-com/net-switchdev-use-struct_size-over-open-coded-arithmetic/20220128-155848
git checkout bf0e33a8c3deb700b95173a37dd16754341ba70e
# save the config file to linux build tree
mkdir build_dir
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=arm SHELL=/bin/bash
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
All errors (new ones prefixed by >>):
>> net/switchdev/switchdev.c:88:19: error: member reference type 'struct switchdev_deferred_item' is not a pointer; did you mean to use '.'?
dfitem = kmalloc(struct_size(*dfitem, data, data_len), GFP_ATOMIC);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/overflow.h:194:18: note: expanded from macro 'struct_size'
sizeof(*(p)->member) + __must_be_array((p)->member),\
~~~^
>> net/switchdev/switchdev.c:88:19: error: indirection requires pointer operand ('unsigned long[]' invalid)
dfitem = kmalloc(struct_size(*dfitem, data, data_len), GFP_ATOMIC);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/overflow.h:194:14: note: expanded from macro 'struct_size'
sizeof(*(p)->member) + __must_be_array((p)->member),\
^~~~~~~~~~~~
>> net/switchdev/switchdev.c:88:19: error: member reference type 'struct switchdev_deferred_item' is not a pointer; did you mean to use '.'?
dfitem = kmalloc(struct_size(*dfitem, data, data_len), GFP_ATOMIC);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/overflow.h:194:49: note: expanded from macro 'struct_size'
sizeof(*(p)->member) + __must_be_array((p)->member),\
~~~~~~~~~~~~~~~~~~~^~~~~~~~~
include/linux/compiler.h:258:59: note: expanded from macro '__must_be_array'
#define __must_be_array(a) BUILD_BUG_ON_ZERO(__same_type((a), &(a)[0]))
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~
include/linux/compiler_types.h:287:63: note: expanded from macro '__same_type'
#define __same_type(a, b) __builtin_types_compatible_p(typeof(a), typeof(b))
^
include/linux/build_bug.h:16:62: note: expanded from macro 'BUILD_BUG_ON_ZERO'
#define BUILD_BUG_ON_ZERO(e) ((int)(sizeof(struct { int:(-!!(e)); })))
^
>> net/switchdev/switchdev.c:88:19: error: member reference type 'struct switchdev_deferred_item' is not a pointer; did you mean to use '.'?
dfitem = kmalloc(struct_size(*dfitem, data, data_len), GFP_ATOMIC);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/overflow.h:194:49: note: expanded from macro 'struct_size'
sizeof(*(p)->member) + __must_be_array((p)->member),\
~~~~~~~~~~~~~~~~~~~^~~~~~~~~
include/linux/compiler.h:258:65: note: expanded from macro '__must_be_array'
#define __must_be_array(a) BUILD_BUG_ON_ZERO(__same_type((a), &(a)[0]))
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~
include/linux/compiler_types.h:287:74: note: expanded from macro '__same_type'
#define __same_type(a, b) __builtin_types_compatible_p(typeof(a), typeof(b))
^
include/linux/build_bug.h:16:62: note: expanded from macro 'BUILD_BUG_ON_ZERO'
#define BUILD_BUG_ON_ZERO(e) ((int)(sizeof(struct { int:(-!!(e)); })))
^
>> net/switchdev/switchdev.c:88:19: error: indirection requires pointer operand ('struct switchdev_deferred_item' invalid)
dfitem = kmalloc(struct_size(*dfitem, data, data_len), GFP_ATOMIC);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/overflow.h:195:14: note: expanded from macro 'struct_size'
sizeof(*(p)))
^~~~
5 errors generated.
vim +88 net/switchdev/switchdev.c
81
82 static int switchdev_deferred_enqueue(struct net_device *dev,
83 const void *data, size_t data_len,
84 switchdev_deferred_func_t *func)
85 {
86 struct switchdev_deferred_item *dfitem;
87
> 88 dfitem = kmalloc(struct_size(*dfitem, data, data_len), GFP_ATOMIC);
89 if (!dfitem)
90 return -ENOMEM;
91 dfitem->dev = dev;
92 dfitem->func = func;
93 memcpy(dfitem->data, data, data_len);
94 dev_hold_track(dev, &dfitem->dev_tracker, GFP_ATOMIC);
95 spin_lock_bh(&deferred_lock);
96 list_add_tail(&dfitem->list, &deferred);
97 spin_unlock_bh(&deferred_lock);
98 schedule_work(&deferred_process_work);
99 return 0;
100 }
101
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
Hi,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on linus/master]
[also build test ERROR on v5.17-rc1 next-20220128]
[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/cgel-zte-gmail-com/net-switchdev-use-struct_size-over-open-coded-arithmetic/20220128-155848
base: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 23a46422c56144939c091c76cf389aa863ce9c18
config: i386-randconfig-a005 (https://download.01.org/0day-ci/archive/20220129/202201290005.GR1IxnQb-lkp@intel.com/config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0
reproduce (this is a W=1 build):
# https://github.com/0day-ci/linux/commit/bf0e33a8c3deb700b95173a37dd16754341ba70e
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review cgel-zte-gmail-com/net-switchdev-use-struct_size-over-open-coded-arithmetic/20220128-155848
git checkout bf0e33a8c3deb700b95173a37dd16754341ba70e
# save the config file to linux build tree
mkdir build_dir
make W=1 O=build_dir ARCH=i386 SHELL=/bin/bash net/
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
All errors (new ones prefixed by >>):
In file included from include/linux/mm.h:30,
from arch/x86/include/asm/cacheflush.h:5,
from include/linux/cacheflush.h:5,
from include/linux/highmem.h:8,
from include/linux/bvec.h:10,
from include/linux/skbuff.h:17,
from include/net/net_namespace.h:40,
from include/linux/netdevice.h:37,
from net/switchdev/switchdev.c:13:
net/switchdev/switchdev.c: In function 'switchdev_deferred_enqueue':
>> include/linux/overflow.h:194:18: error: invalid type argument of '->' (have 'struct switchdev_deferred_item')
194 | sizeof(*(p)->member) + __must_be_array((p)->member),\
| ^~
net/switchdev/switchdev.c:88:19: note: in expansion of macro 'struct_size'
88 | dfitem = kmalloc(struct_size(*dfitem, data, data_len), GFP_ATOMIC);
| ^~~~~~~~~~~
In file included from include/linux/container_of.h:5,
from include/linux/kernel.h:21,
from net/switchdev/switchdev.c:8:
include/linux/overflow.h:194:49: error: invalid type argument of '->' (have 'struct switchdev_deferred_item')
194 | sizeof(*(p)->member) + __must_be_array((p)->member),\
| ^~
include/linux/build_bug.h:16:62: note: in definition of macro 'BUILD_BUG_ON_ZERO'
16 | #define BUILD_BUG_ON_ZERO(e) ((int)(sizeof(struct { int:(-!!(e)); })))
| ^
include/linux/compiler.h:258:46: note: in expansion of macro '__same_type'
258 | #define __must_be_array(a) BUILD_BUG_ON_ZERO(__same_type((a), &(a)[0]))
| ^~~~~~~~~~~
include/linux/overflow.h:194:30: note: in expansion of macro '__must_be_array'
194 | sizeof(*(p)->member) + __must_be_array((p)->member),\
| ^~~~~~~~~~~~~~~
net/switchdev/switchdev.c:88:19: note: in expansion of macro 'struct_size'
88 | dfitem = kmalloc(struct_size(*dfitem, data, data_len), GFP_ATOMIC);
| ^~~~~~~~~~~
include/linux/overflow.h:194:49: error: invalid type argument of '->' (have 'struct switchdev_deferred_item')
194 | sizeof(*(p)->member) + __must_be_array((p)->member),\
| ^~
include/linux/build_bug.h:16:62: note: in definition of macro 'BUILD_BUG_ON_ZERO'
16 | #define BUILD_BUG_ON_ZERO(e) ((int)(sizeof(struct { int:(-!!(e)); })))
| ^
include/linux/compiler.h:258:46: note: in expansion of macro '__same_type'
258 | #define __must_be_array(a) BUILD_BUG_ON_ZERO(__same_type((a), &(a)[0]))
| ^~~~~~~~~~~
include/linux/overflow.h:194:30: note: in expansion of macro '__must_be_array'
194 | sizeof(*(p)->member) + __must_be_array((p)->member),\
| ^~~~~~~~~~~~~~~
net/switchdev/switchdev.c:88:19: note: in expansion of macro 'struct_size'
88 | dfitem = kmalloc(struct_size(*dfitem, data, data_len), GFP_ATOMIC);
| ^~~~~~~~~~~
include/linux/build_bug.h:16:51: error: bit-field '<anonymous>' width not an integer constant
16 | #define BUILD_BUG_ON_ZERO(e) ((int)(sizeof(struct { int:(-!!(e)); })))
| ^
include/linux/compiler.h:258:28: note: in expansion of macro 'BUILD_BUG_ON_ZERO'
258 | #define __must_be_array(a) BUILD_BUG_ON_ZERO(__same_type((a), &(a)[0]))
| ^~~~~~~~~~~~~~~~~
include/linux/overflow.h:194:30: note: in expansion of macro '__must_be_array'
194 | sizeof(*(p)->member) + __must_be_array((p)->member),\
| ^~~~~~~~~~~~~~~
net/switchdev/switchdev.c:88:19: note: in expansion of macro 'struct_size'
88 | dfitem = kmalloc(struct_size(*dfitem, data, data_len), GFP_ATOMIC);
| ^~~~~~~~~~~
In file included from include/linux/mm.h:30,
from arch/x86/include/asm/cacheflush.h:5,
from include/linux/cacheflush.h:5,
from include/linux/highmem.h:8,
from include/linux/bvec.h:10,
from include/linux/skbuff.h:17,
from include/net/net_namespace.h:40,
from include/linux/netdevice.h:37,
from net/switchdev/switchdev.c:13:
>> include/linux/overflow.h:195:14: error: invalid type argument of unary '*' (have 'struct switchdev_deferred_item')
195 | sizeof(*(p)))
| ^~~~
net/switchdev/switchdev.c:88:19: note: in expansion of macro 'struct_size'
88 | dfitem = kmalloc(struct_size(*dfitem, data, data_len), GFP_ATOMIC);
| ^~~~~~~~~~~
vim +194 include/linux/overflow.h
610b15c50e86eb Kees Cook 2018-05-07 180
610b15c50e86eb Kees Cook 2018-05-07 181 /**
610b15c50e86eb Kees Cook 2018-05-07 182 * struct_size() - Calculate size of structure with trailing array.
610b15c50e86eb Kees Cook 2018-05-07 183 * @p: Pointer to the structure.
610b15c50e86eb Kees Cook 2018-05-07 184 * @member: Name of the array member.
b19d57d0f3cc6f Gustavo A. R. Silva 2020-06-08 185 * @count: Number of elements in the array.
610b15c50e86eb Kees Cook 2018-05-07 186 *
610b15c50e86eb Kees Cook 2018-05-07 187 * Calculates size of memory needed for structure @p followed by an
b19d57d0f3cc6f Gustavo A. R. Silva 2020-06-08 188 * array of @count number of @member elements.
610b15c50e86eb Kees Cook 2018-05-07 189 *
610b15c50e86eb Kees Cook 2018-05-07 190 * Return: number of bytes needed or SIZE_MAX on overflow.
610b15c50e86eb Kees Cook 2018-05-07 191 */
b19d57d0f3cc6f Gustavo A. R. Silva 2020-06-08 192 #define struct_size(p, member, count) \
b19d57d0f3cc6f Gustavo A. R. Silva 2020-06-08 193 __ab_c_size(count, \
610b15c50e86eb Kees Cook 2018-05-07 @194 sizeof(*(p)->member) + __must_be_array((p)->member),\
610b15c50e86eb Kees Cook 2018-05-07 @195 sizeof(*(p)))
610b15c50e86eb Kees Cook 2018-05-07 196
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
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