tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head: 30185b69a2d533c4ba6ca926b8390ce7de495e29
commit: 4b7ca5014cbef51cdb99fd644eae4f3773747a05 init: add an init_chroot helper
date: 8 days ago
compiler: hppa-linux-gcc (GCC) 9.3.0
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <[email protected]>
cppcheck warnings: (new ones prefixed by >>)
>> fs/init.c:72:8: warning: Variable 'error' is reassigned a value before the old one has been used. [redundantAssignment]
error = security_path_chroot(&path);
^
fs/init.c:69:8: note: Variable 'error' is reassigned a value before the old one has been used.
error = -EPERM;
^
fs/init.c:72:8: note: Variable 'error' is reassigned a value before the old one has been used.
error = security_path_chroot(&path);
^
vim +/error +72 fs/init.c
57
58 int __init init_chroot(const char *filename)
59 {
60 struct path path;
61 int error;
62
63 error = kern_path(filename, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path);
64 if (error)
65 return error;
66 error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
67 if (error)
68 goto dput_and_out;
69 error = -EPERM;
70 if (!ns_capable(current_user_ns(), CAP_SYS_CHROOT))
71 goto dput_and_out;
> 72 error = security_path_chroot(&path);
73 if (error)
74 goto dput_and_out;
75 set_fs_root(current->fs, &path);
76 dput_and_out:
77 path_put(&path);
78 return error;
79 }
80
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/[email protected]
On Sat, Aug 08, 2020 at 11:35:45AM +0800, kernel test robot wrote:
> tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> head: 30185b69a2d533c4ba6ca926b8390ce7de495e29
> commit: 4b7ca5014cbef51cdb99fd644eae4f3773747a05 init: add an init_chroot helper
> date: 8 days ago
> compiler: hppa-linux-gcc (GCC) 9.3.0
>
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <[email protected]>
>
>
> cppcheck warnings: (new ones prefixed by >>)
>
> >> fs/init.c:72:8: warning: Variable 'error' is reassigned a value before the old one has been used. [redundantAssignment]
> error = security_path_chroot(&path);
> ^
> fs/init.c:69:8: note: Variable 'error' is reassigned a value before the old one has been used.
> error = -EPERM;
> ^
> fs/init.c:72:8: note: Variable 'error' is reassigned a value before the old one has been used.
> error = security_path_chroot(&path);
I really don't understand the warning. We assign a value to error, if
there is an error we jump the out labe and return it, or else continue.
That is a pretty common pattern in the kernel. What do I miss?
>
> vim +/error +72 fs/init.c
>
> 57
> 58 int __init init_chroot(const char *filename)
> 59 {
> 60 struct path path;
> 61 int error;
> 62
> 63 error = kern_path(filename, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path);
> 64 if (error)
> 65 return error;
> 66 error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
> 67 if (error)
> 68 goto dput_and_out;
> 69 error = -EPERM;
> 70 if (!ns_capable(current_user_ns(), CAP_SYS_CHROOT))
> 71 goto dput_and_out;
> > 72 error = security_path_chroot(&path);
> 73 if (error)
> 74 goto dput_and_out;
> 75 set_fs_root(current->fs, &path);
> 76 dput_and_out:
> 77 path_put(&path);
> 78 return error;
> 79 }
> 80
>
> ---
> 0-DAY CI Kernel Test Service, Intel Corporation
> https://lists.01.org/hyperkitty/list/[email protected]
---end quoted text---
>-----Original Message-----
>From: Christoph Hellwig <[email protected]>
>Sent: 2020年8月8日 13:40
>To: kernel test robot <[email protected]>
>Cc: Christoph Hellwig <[email protected]>; [email protected]; linux-
>[email protected]; [email protected]
>Subject: [kbuild-all] Re: fs/init.c:72:8: warning: Variable 'error' is reassigned a
>value before the old one has been used.
>
>On Sat, Aug 08, 2020 at 11:35:45AM +0800, kernel test robot wrote:
>> tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
>> head: 30185b69a2d533c4ba6ca926b8390ce7de495e29
>> commit: 4b7ca5014cbef51cdb99fd644eae4f3773747a05 init: add an init_chroot
>helper
>> date: 8 days ago
>> compiler: hppa-linux-gcc (GCC) 9.3.0
>>
>> If you fix the issue, kindly add following tag as appropriate
>> Reported-by: kernel test robot <[email protected]>
>>
>>
>> cppcheck warnings: (new ones prefixed by >>)
>>
>> >> fs/init.c:72:8: warning: Variable 'error' is reassigned a value
>> >> before the old one has been used. [redundantAssignment]
>> error = security_path_chroot(&path);
>> ^
>> fs/init.c:69:8: note: Variable 'error' is reassigned a value before the old one
>has been used.
>> error = -EPERM;
>> ^
>> fs/init.c:72:8: note: Variable 'error' is reassigned a value before the old one
>has been used.
>> error = security_path_chroot(&path);
>
>I really don't understand the warning. We assign a value to error, if there is an
>error we jump the out labe and return it, or else continue.
>
>That is a pretty common pattern in the kernel. What do I miss?
Please ignore this report. It is false positive.
We will double check this type of warning in future. Sorry for inconvenient.
Thanks,
Hui
>
>>
>> vim +/error +72 fs/init.c
>>
>> 57
>> 58 int __init init_chroot(const char *filename)
>> 59 {
>> 60 struct path path;
>> 61 int error;
>> 62
>> 63 error = kern_path(filename, LOOKUP_FOLLOW |
>LOOKUP_DIRECTORY, &path);
>> 64 if (error)
>> 65 return error;
>> 66 error = inode_permission(path.dentry->d_inode, MAY_EXEC |
>MAY_CHDIR);
>> 67 if (error)
>> 68 goto dput_and_out;
>> 69 error = -EPERM;
>> 70 if (!ns_capable(current_user_ns(), CAP_SYS_CHROOT))
>> 71 goto dput_and_out;
>> > 72 error = security_path_chroot(&path);
>> 73 if (error)
>> 74 goto dput_and_out;
>> 75 set_fs_root(current->fs, &path);
>> 76 dput_and_out:
>> 77 path_put(&path);
>> 78 return error;
>> 79 }
>> 80
>>
>> ---
>> 0-DAY CI Kernel Test Service, Intel Corporation
>> https://lists.01.org/hyperkitty/list/[email protected]
>---end quoted text---
>_______________________________________________
>kbuild-all mailing list -- [email protected] To unsubscribe send an email to
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