net/ipv4/ip_sockglue.c:838:7: warning: taking address of packed member 'gf_group' of class or structure 'compat_group_filter::(anonymous union)::(anonymous)' may result in an unaligned pointer value
From: kernel test robot
Date: Sun Jul 24 2022 - 22:12:59 EST
Hi Gustavo,
FYI, the error/warning still remains.
tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head: e0dccc3b76fb35bb257b4118367a883073d7390e
commit: db243b796439c0caba47865564d8acd18a301d18 net/ipv4/ipv6: Replace one-element arraya with flexible-array members
date: 12 months ago
config: arm-colibri_pxa300_defconfig (https://download.01.org/0day-ci/archive/20220725/202207251043.l8Cq3k4Z-lkp@xxxxxxxxx/config)
compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project 12fbd2d377e396ad61bce56d71c98a1eb1bebfa9)
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://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=db243b796439c0caba47865564d8acd18a301d18
git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
git fetch --no-tags linus master
git checkout db243b796439c0caba47865564d8acd18a301d18
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=arm SHELL=/bin/bash net/ipv4/ net/ipv6/
If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@xxxxxxxxx>
All warnings (new ones prefixed by >>):
>> net/ipv4/ip_sockglue.c:838:7: warning: taking address of packed member 'gf_group' of class or structure 'compat_group_filter::(anonymous union)::(anonymous)' may result in an unaligned pointer value [-Waddress-of-packed-member]
&gf32->gf_group, gf32->gf_slist_flex);
^~~~~~~~~~~~~~
>> net/ipv4/ip_sockglue.c:1509:29: warning: taking address of packed member 'gf_fmode' of class or structure 'compat_group_filter::(anonymous union)::(anonymous)' may result in an unaligned pointer value [-Waddress-of-packed-member]
put_user(gf.gf_fmode, &p->gf_fmode) ||
^~~~~~~~~~~
arch/arm/include/asm/uaccess.h:406:26: note: expanded from macro 'put_user'
__put_user_switch((x), (ptr), __pu_err, __put_user_check); \
^~~
arch/arm/include/asm/uaccess.h:388:22: note: expanded from macro '__put_user_switch'
const __typeof__(*(ptr)) __user *__pu_ptr = (ptr); \
^~~
>> net/ipv4/ip_sockglue.c:1509:29: warning: taking address of packed member 'gf_fmode' of class or structure 'compat_group_filter::(anonymous union)::(anonymous)' may result in an unaligned pointer value [-Waddress-of-packed-member]
put_user(gf.gf_fmode, &p->gf_fmode) ||
^~~~~~~~~~~
arch/arm/include/asm/uaccess.h:406:26: note: expanded from macro 'put_user'
__put_user_switch((x), (ptr), __pu_err, __put_user_check); \
^~~
arch/arm/include/asm/uaccess.h:389:16: note: expanded from macro '__put_user_switch'
__typeof__(*(ptr)) __pu_val = (x); \
^~~
>> net/ipv4/ip_sockglue.c:1509:29: warning: taking address of packed member 'gf_fmode' of class or structure 'compat_group_filter::(anonymous union)::(anonymous)' may result in an unaligned pointer value [-Waddress-of-packed-member]
put_user(gf.gf_fmode, &p->gf_fmode) ||
^~~~~~~~~~~
arch/arm/include/asm/uaccess.h:406:26: note: expanded from macro 'put_user'
__put_user_switch((x), (ptr), __pu_err, __put_user_check); \
^~~
arch/arm/include/asm/uaccess.h:393:20: note: expanded from macro '__put_user_switch'
switch (sizeof(*(ptr))) { \
^~~
>> net/ipv4/ip_sockglue.c:1510:30: warning: taking address of packed member 'gf_numsrc' of class or structure 'compat_group_filter::(anonymous union)::(anonymous)' may result in an unaligned pointer value [-Waddress-of-packed-member]
put_user(gf.gf_numsrc, &p->gf_numsrc))
^~~~~~~~~~~~
arch/arm/include/asm/uaccess.h:406:26: note: expanded from macro 'put_user'
__put_user_switch((x), (ptr), __pu_err, __put_user_check); \
^~~
arch/arm/include/asm/uaccess.h:388:22: note: expanded from macro '__put_user_switch'
const __typeof__(*(ptr)) __user *__pu_ptr = (ptr); \
^~~
>> net/ipv4/ip_sockglue.c:1510:30: warning: taking address of packed member 'gf_numsrc' of class or structure 'compat_group_filter::(anonymous union)::(anonymous)' may result in an unaligned pointer value [-Waddress-of-packed-member]
put_user(gf.gf_numsrc, &p->gf_numsrc))
^~~~~~~~~~~~
arch/arm/include/asm/uaccess.h:406:26: note: expanded from macro 'put_user'
__put_user_switch((x), (ptr), __pu_err, __put_user_check); \
^~~
arch/arm/include/asm/uaccess.h:389:16: note: expanded from macro '__put_user_switch'
__typeof__(*(ptr)) __pu_val = (x); \
^~~
>> net/ipv4/ip_sockglue.c:1510:30: warning: taking address of packed member 'gf_numsrc' of class or structure 'compat_group_filter::(anonymous union)::(anonymous)' may result in an unaligned pointer value [-Waddress-of-packed-member]
put_user(gf.gf_numsrc, &p->gf_numsrc))
^~~~~~~~~~~~
arch/arm/include/asm/uaccess.h:406:26: note: expanded from macro 'put_user'
__put_user_switch((x), (ptr), __pu_err, __put_user_check); \
^~~
arch/arm/include/asm/uaccess.h:393:20: note: expanded from macro '__put_user_switch'
switch (sizeof(*(ptr))) { \
^~~
7 warnings generated.
--
>> net/ipv6/ipv6_sockglue.c:1111:29: warning: taking address of packed member 'gf_fmode' of class or structure 'compat_group_filter::(anonymous union)::(anonymous)' may result in an unaligned pointer value [-Waddress-of-packed-member]
put_user(gf.gf_fmode, &p->gf_fmode) ||
^~~~~~~~~~~
arch/arm/include/asm/uaccess.h:406:26: note: expanded from macro 'put_user'
__put_user_switch((x), (ptr), __pu_err, __put_user_check); \
^~~
arch/arm/include/asm/uaccess.h:388:22: note: expanded from macro '__put_user_switch'
const __typeof__(*(ptr)) __user *__pu_ptr = (ptr); \
^~~
>> net/ipv6/ipv6_sockglue.c:1111:29: warning: taking address of packed member 'gf_fmode' of class or structure 'compat_group_filter::(anonymous union)::(anonymous)' may result in an unaligned pointer value [-Waddress-of-packed-member]
put_user(gf.gf_fmode, &p->gf_fmode) ||
^~~~~~~~~~~
arch/arm/include/asm/uaccess.h:406:26: note: expanded from macro 'put_user'
__put_user_switch((x), (ptr), __pu_err, __put_user_check); \
^~~
arch/arm/include/asm/uaccess.h:389:16: note: expanded from macro '__put_user_switch'
__typeof__(*(ptr)) __pu_val = (x); \
^~~
>> net/ipv6/ipv6_sockglue.c:1111:29: warning: taking address of packed member 'gf_fmode' of class or structure 'compat_group_filter::(anonymous union)::(anonymous)' may result in an unaligned pointer value [-Waddress-of-packed-member]
put_user(gf.gf_fmode, &p->gf_fmode) ||
^~~~~~~~~~~
arch/arm/include/asm/uaccess.h:406:26: note: expanded from macro 'put_user'
__put_user_switch((x), (ptr), __pu_err, __put_user_check); \
^~~
arch/arm/include/asm/uaccess.h:393:20: note: expanded from macro '__put_user_switch'
switch (sizeof(*(ptr))) { \
^~~
>> net/ipv6/ipv6_sockglue.c:1112:30: warning: taking address of packed member 'gf_numsrc' of class or structure 'compat_group_filter::(anonymous union)::(anonymous)' may result in an unaligned pointer value [-Waddress-of-packed-member]
put_user(gf.gf_numsrc, &p->gf_numsrc))
^~~~~~~~~~~~
arch/arm/include/asm/uaccess.h:406:26: note: expanded from macro 'put_user'
__put_user_switch((x), (ptr), __pu_err, __put_user_check); \
^~~
arch/arm/include/asm/uaccess.h:388:22: note: expanded from macro '__put_user_switch'
const __typeof__(*(ptr)) __user *__pu_ptr = (ptr); \
^~~
>> net/ipv6/ipv6_sockglue.c:1112:30: warning: taking address of packed member 'gf_numsrc' of class or structure 'compat_group_filter::(anonymous union)::(anonymous)' may result in an unaligned pointer value [-Waddress-of-packed-member]
put_user(gf.gf_numsrc, &p->gf_numsrc))
^~~~~~~~~~~~
arch/arm/include/asm/uaccess.h:406:26: note: expanded from macro 'put_user'
__put_user_switch((x), (ptr), __pu_err, __put_user_check); \
^~~
arch/arm/include/asm/uaccess.h:389:16: note: expanded from macro '__put_user_switch'
__typeof__(*(ptr)) __pu_val = (x); \
^~~
>> net/ipv6/ipv6_sockglue.c:1112:30: warning: taking address of packed member 'gf_numsrc' of class or structure 'compat_group_filter::(anonymous union)::(anonymous)' may result in an unaligned pointer value [-Waddress-of-packed-member]
put_user(gf.gf_numsrc, &p->gf_numsrc))
^~~~~~~~~~~~
arch/arm/include/asm/uaccess.h:406:26: note: expanded from macro 'put_user'
__put_user_switch((x), (ptr), __pu_err, __put_user_check); \
^~~
arch/arm/include/asm/uaccess.h:393:20: note: expanded from macro '__put_user_switch'
switch (sizeof(*(ptr))) { \
^~~
6 warnings generated.
vim +838 net/ipv4/ip_sockglue.c
799
800 static int compat_ip_set_mcast_msfilter(struct sock *sk, sockptr_t optval,
801 int optlen)
802 {
803 const int size0 = offsetof(struct compat_group_filter, gf_slist_flex);
804 struct compat_group_filter *gf32;
805 unsigned int n;
806 void *p;
807 int err;
808
809 if (optlen < size0)
810 return -EINVAL;
811 if (optlen > sysctl_optmem_max - 4)
812 return -ENOBUFS;
813
814 p = kmalloc(optlen + 4, GFP_KERNEL);
815 if (!p)
816 return -ENOMEM;
817 gf32 = p + 4; /* we want ->gf_group and ->gf_slist_flex aligned */
818
819 err = -EFAULT;
820 if (copy_from_sockptr(gf32, optval, optlen))
821 goto out_free_gsf;
822
823 /* numsrc >= (4G-140)/128 overflow in 32 bits */
824 n = gf32->gf_numsrc;
825 err = -ENOBUFS;
826 if (n >= 0x1ffffff)
827 goto out_free_gsf;
828
829 err = -EINVAL;
830 if (offsetof(struct compat_group_filter, gf_slist_flex[n]) > optlen)
831 goto out_free_gsf;
832
833 /* numsrc >= (4G-140)/128 overflow in 32 bits */
834 err = -ENOBUFS;
835 if (n > sock_net(sk)->ipv4.sysctl_igmp_max_msf)
836 goto out_free_gsf;
837 err = set_mcast_msfilter(sk, gf32->gf_interface, n, gf32->gf_fmode,
> 838 &gf32->gf_group, gf32->gf_slist_flex);
839 out_free_gsf:
840 kfree(p);
841 return err;
842 }
843
--
0-DAY CI Kernel Test Service
https://01.org/lkp