lsm: constify the 'mm' parameter in security_vm_enough_memory_mm()
Subsystems (5)
PATCH 1/1 lsm: constify the 'mm' parameter in security_vm_enough_memory_mm()
The 'vm_enough_memory' hook has implementations registered in SELinux and commoncap. Looking at the function implementations we observe that the 'mm' parameter is not changing.
Mark the 'mm' parameter of LSM hook security_vm_enough_memory_mm() as 'const' since it will not be changing in the LSM hook.
Signed-off-by Khadija Kamran <[email protected]>
--- include/linux/lsm_hook_defs.h | 2 +- include/linux/mm.h | 2 +- include/linux/security.h | 6 +++--- security/commoncap.c | 2 +- security/security.c | 2 +- security/selinux/hooks.c | 2 +- 6 files changed, 8 insertions(+), 8 deletions(-)
include/linux/lsm_hook_defs.h +1 -1
@@ -48,7 +48,7 @@ LSM_HOOK(int, 0, quota_on, struct dentry *dentry) LSM_HOOK(int, 0, syslog, int type) LSM_HOOK(int, 0, settime, const struct timespec64 *ts, const struct timezone *tz) -LSM_HOOK(int, 0, vm_enough_memory, struct mm_struct *mm, long pages) +LSM_HOOK(int, 0, vm_enough_memory, const struct mm_struct *mm, long pages) LSM_HOOK(int, 0, bprm_creds_for_exec, struct linux_binprm *bprm) LSM_HOOK(int, 0, bprm_creds_from_file, struct linux_binprm *bprm, struct file *file) LSM_HOOK(int, 0, bprm_check_security, struct linux_binprm *bprm)
include/linux/mm.h +1 -1
@@ -3064,7 +3064,7 @@ void anon_vma_interval_tree_verify(struct anon_vma_chain *node); avc; avc = anon_vma_interval_tree_iter_next(avc, start, last))/* mmap.c */ -extern int __vm_enough_memory (struct mm_struct *mm,long pages,int cap_sys_admin); +extern int __vm_enough_memory (const struct mm_struct *mm,long pages,int cap_sys_admin);extern int vma_expand (struct vma_iterator *vmi,struct vm_area_struct *vma,unsigned long start,unsigned long end,pgoff_t pgoff,struct vm_area_struct *next);
include/linux/security.h +3 -3
@@ -169,7 +169,7 @@ extern int cap_task_prctl(int option, unsigned long arg2, unsigned long arg3,extern int cap_task_setscheduler (struct task_struct *p);extern int cap_task_setioprio (struct task_struct *p,int ioprio);extern int cap_task_setnice (struct task_struct *p,int nice); -extern int cap_vm_enough_memory (struct mm_struct *mm,long pages); +extern int cap_vm_enough_memory (const struct mm_struct *mm,long pages);struct msghdr ;struct sk_buff ;
@@ -287,7 +287,7 @@ int security_quotactl(int cmds, int type, int id, struct super_block *sb);int security_quota_on (struct dentry *dentry);int security_syslog (int type);int security_settime64 (const struct timespec64 *ts,const struct timezone *tz); -int security_vm_enough_memory_mm (struct mm_struct *mm,long pages); +int security_vm_enough_memory_mm (const struct mm_struct *mm,long pages);int security_bprm_creds_for_exec (struct linux_binprm *bprm);int security_bprm_creds_from_file (struct linux_binprm *bprm,struct file *file);int security_bprm_check (struct linux_binprm *bprm);
@@ -600,7 +600,7 @@ static inline int security_settime64(const struct timespec64 *ts,return cap_settime (ts, tz); } -static inline int security_vm_enough_memory_mm (struct mm_struct *mm,long pages) +static inline int security_vm_enough_memory_mm (const struct mm_struct *mm,long pages) {return __vm_enough_memory (mm, pages,cap_vm_enough_memory (mm, pages)); }
security/commoncap.c +1 -1
@@ -1397,7 +1397,7 @@ int cap_task_prctl(int option, unsigned long arg2, unsigned long arg3,* * Return: 1 if permission is granted, 0 if not. */ -int cap_vm_enough_memory (struct mm_struct *mm,long pages) +int cap_vm_enough_memory (const struct mm_struct *mm,long pages) {int cap_sys_admin =0 ;
security/security.c +1 -1
@@ -1017,7 +1017,7 @@ int security_settime64(const struct timespec64 *ts, const struct timezone *tz)* Return: Returns 0 if permission is granted by the LSM infrastructure to the * caller. */ -int security_vm_enough_memory_mm (struct mm_struct *mm,long pages) +int security_vm_enough_memory_mm (const struct mm_struct *mm,long pages) {struct security_hook_list *hp;int cap_sys_admin =1 ;
security/selinux/hooks.c +1 -1
@@ -2158,7 +2158,7 @@ static int selinux_syslog(int type)* Do not audit the selinux permission check, as this is applied to all * processes that allocate mappings. */ -static int selinux_vm_enough_memory (struct mm_struct *mm,long pages) +static int selinux_vm_enough_memory (const struct mm_struct *mm,long pages) {int rc, cap_sys_admin =0 ;
Signature · 1 line
2.34.1
include/linux/mm.h void anon_vma_interval_tree_verify(struct anon_vma_chain *node); · line 3067
Quoted 7 lines · Khadija Kamran
+++
b/include/linux/mm.hinclude/linux/mm.h +1
-1@@ -3064,7 +3064,7 @@ void anon_vma_interval_tree_verify(struct anon_vma_chain *node); avc; avc = anon_vma_interval_tree_iter_next(avc, start, last))/* mmap.c */ -extern int __vm_enough_memory (struct mm_struct *mm,long pages,int cap_sys_admin); +extern int __vm_enough_memory (const struct mm_struct *mm,long pages,int cap_sys_admin);
Could you remove the 'extern' when you touch a function prototype?
Paul Moore
maintainerQuoted 10 lines · Matthew Wilcox
include/linux/mm.h void anon_vma_interval_tree_verify(struct anon_vma_chain *node); · line 3067
Quoted 7 lines · Khadija Kamran
+++
b/include/linux/mm.hinclude/linux/mm.h +1
-1@@ -3064,7 +3064,7 @@ void anon_vma_interval_tree_verify(struct anon_vma_chain *node); avc; avc = anon_vma_interval_tree_iter_next(avc, start, last))/* mmap.c */ -extern int __vm_enough_memory (struct mm_struct *mm,long pages,int cap_sys_admin); +extern int __vm_enough_memory (const struct mm_struct *mm,long pages,int cap_sys_admin);Could you remove the 'extern' when you touch a function prototype?
Khadija, can you please make the change Matthew is requesting?
Signature · 1 line
paul-moore.com
kernel test robot
build botkernel test robot noticed the following build errors:
Hi Khadija,
kernel test robot noticed the following build errors:
[auto build test ERROR on akpm-mm/mm-everything]
[also build test ERROR on pcmoore-selinux/next pcmoore-audit/next linus/master v6.5-rc7 next-20230824] [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#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Khadija-Kamran/lsm-constify-the-mm-parameter-in-security_vm_enough_memory_mm/20230823-145455 base: https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything patch link: https://lore.kernel.org/r/ZOWtBTKkfcc8sKkY%40gmail.com patch subject: [PATCH] lsm: constify the 'mm' parameter in security_vm_enough_memory_mm() config: arc-randconfig-001-20230824 (https://download.01.org/0day-ci/archive/20230824/[email protected]/config) compiler: arc-elf-gcc (GCC) 13.2.0 reproduce: (https://download.01.org/0day-ci/archive/20230824/[email protected]/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <[email protected]>
| Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
All errors (new ones prefixed by >>):
>> mm/util.c:928:5: error: conflicting types for '__vm_enough_memory'; have 'int(struct mm_struct *, long int, int)'
928 | int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin)
| ^~~~~~~~~~~~~~~~~~
In file included from mm/util.c:2:
include/linux/mm.h:3199:12: note: previous declaration of '__vm_enough_memory' with type 'int(const struct mm_struct *, long int, int)'
3199 | extern int __vm_enough_memory(const struct mm_struct *mm, long pages, int cap_sys_admin);
| ^~~~~~~~~~~~~~~~~~vim +928 mm/util.c
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 911
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 912 /*
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 913 * Check that a process has enough memory to allocate a new virtual
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 914 * mapping. 0 means there is enough memory for the allocation to
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 915 * succeed and -ENOMEM implies there is not.
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 916 *
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 917 * We currently support three overcommit policies, which are set via the
ee65728e103bb7 Mike Rapoport 2022-06-27 918 * vm.overcommit_memory sysctl. See Documentation/mm/overcommit-accounting.rst
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 919 *
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 920 * Strict overcommit modes added 2002 Feb 26 by Alan Cox.
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 921 * Additional code 2002 Jul 20 by Robert Love.
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 922 *
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 923 * cap_sys_admin is 1 if the process has admin privileges, 0 otherwise.
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 924 *
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 925 * Note this is a helper function intended to be used by LSMs which
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 926 * wish to use this logic.
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 927 */
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 @928 int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin)
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 929 {
8c7829b04c523c Johannes Weiner 2019-05-13 930 long allowed;
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 931
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 932 vm_acct_memory(pages);
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 933
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 934 /*
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 935 * Sometimes we want to use more memory than we have
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 936 */
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 937 if (sysctl_overcommit_memory == OVERCOMMIT_ALWAYS)
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 938 return 0;
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 939
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 940 if (sysctl_overcommit_memory == OVERCOMMIT_GUESS) {
8c7829b04c523c Johannes Weiner 2019-05-13 941 if (pages > totalram_pages() + total_swap_pages)
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 942 goto error;
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 943 return 0;
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 944 }
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 945
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 946 allowed = vm_commit_limit();
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 947 /*
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 948 * Reserve some for root
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 949 */
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 950 if (!cap_sys_admin)
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 951 allowed -= sysctl_admin_reserve_kbytes >> (PAGE_SHIFT - 10);
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 952
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 953 /*
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 954 * Don't let a single process grow so big a user can't recover
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 955 */
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 956 if (mm) {
8c7829b04c523c Johannes Weiner 2019-05-13 957 long reserve = sysctl_user_reserve_kbytes >> (PAGE_SHIFT - 10);
8c7829b04c523c Johannes Weiner 2019-05-13 958
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 959 allowed -= min_t(long, mm->total_vm / 32, reserve);
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 960 }
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 961
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 962 if (percpu_counter_read_positive(&vm_committed_as) < allowed)
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 963 return 0;
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 964 error:
6bdfc60cf0f977 Jakub Wilk 2023-02-10 965 pr_warn_ratelimited("%s: pid: %d, comm: %s, not enough memory for the allocation\n",
44b414c8715c5d Kefeng Wang 2022-07-26 966 __func__, current->pid, current->comm);
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 967 vm_unacct_memory(pages);
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 968
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 969 return -ENOMEM;
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 970 }
39a1aa8e194ab6 Andrey Ryabinin 2016-03-17 971 Signature · 2 lines
0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki
Paul Moore
maintainerQuoted 26 lines · kernel test robot
Hi Khadija,
kernel test robot noticed the following build errors:
[auto build test ERROR on akpm-mm/mm-everything]
[also build test ERROR on pcmoore-selinux/next pcmoore-audit/next linus/master v6.5-rc7 next-20230824] [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#_base_tree_information]url: https://github.com/intel-lab-lkp/linux/commits/Khadija-Kamran/lsm-constify-the-mm-parameter-in-security_vm_enough_memory_mm/20230823-145455 base: https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything patch link: https://lore.kernel.org/r/ZOWtBTKkfcc8sKkY%40gmail.com patch subject: [PATCH] lsm: constify the 'mm' parameter in security_vm_enough_memory_mm() config: arc-randconfig-001-20230824 (https://download.01.org/0day-ci/archive/20230824/[email protected]/config) compiler: arc-elf-gcc (GCC) 13.2.0 reproduce: (https://download.01.org/0day-ci/archive/20230824/[email protected]/reproduce)If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <[email protected]>
| Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/All errors (new ones prefixed by >>):
Quoted 7 lines
Quoted 1 line
Quoted 1 line
mm/util.c:928:5: error: conflicting types for '__vm_enough_memory'; have 'int(struct mm_struct *, long int, int)'928 | int
__vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin)
| ^~~~~~~~~~~~~~~~~~
In file included frommm/util.c:2:include/linux/mm.h:3199:12: note: previous declaration of '__vm_enough_memory' with type 'int(const struct mm_struct *, long int, int)' 3199 | extern int __vm_enough_memory(const struct mm_struct *mm, long pages, int cap_sys_admin); | ^~~~~~~~~~~~~~~~~~
It looks like you will also need to update the __vm_enough_memory() definition to take a const mm_struct parameter. I looked quickly at the function just now and I don't think that will be a problem.
Signature · 1 line
paul-moore.com