diff options
Diffstat (limited to 'mm/util.c')
| -rw-r--r-- | mm/util.c | 34 |
1 files changed, 24 insertions, 10 deletions
diff --git a/mm/util.c b/mm/util.c index 41b47d8cae09..c63c8e47be57 100644 --- a/mm/util.c +++ b/mm/util.c @@ -425,7 +425,7 @@ void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack) * @bypass_rlim: %true if checking RLIMIT_MEMLOCK should be skipped * * Assumes @task and @mm are valid (i.e. at least one reference on each), and - * that mmap_sem is held as writer. + * that mmap_lock is held as writer. * * Return: * * 0 on success @@ -437,7 +437,7 @@ int __account_locked_vm(struct mm_struct *mm, unsigned long pages, bool inc, unsigned long locked_vm, limit; int ret = 0; - lockdep_assert_held_write(&mm->mmap_sem); + mmap_assert_write_locked(mm); locked_vm = mm->locked_vm; if (inc) { @@ -481,10 +481,10 @@ int account_locked_vm(struct mm_struct *mm, unsigned long pages, bool inc) if (pages == 0 || !mm) return 0; - down_write(&mm->mmap_sem); + mmap_write_lock(mm); ret = __account_locked_vm(mm, pages, inc, current, capable(CAP_IPC_LOCK)); - up_write(&mm->mmap_sem); + mmap_write_unlock(mm); return ret; } @@ -501,11 +501,11 @@ unsigned long vm_mmap_pgoff(struct file *file, unsigned long addr, ret = security_mmap_file(file, prot, flag); if (!ret) { - if (down_write_killable(&mm->mmap_sem)) + if (mmap_write_lock_killable(mm)) return -EINTR; ret = do_mmap_pgoff(file, addr, len, prot, flag, pgoff, &populate, &uf); - up_write(&mm->mmap_sem); + mmap_write_unlock(mm); userfaultfd_unmap_complete(mm, &uf); if (populate) mm_populate(ret, populate); @@ -604,6 +604,24 @@ void kvfree(const void *addr) } EXPORT_SYMBOL(kvfree); +/** + * kvfree_sensitive - Free a data object containing sensitive information. + * @addr: address of the data object to be freed. + * @len: length of the data object. + * + * Use the special memzero_explicit() function to clear the content of a + * kvmalloc'ed object containing sensitive data to make sure that the + * compiler won't optimize out the data clearing. + */ +void kvfree_sensitive(const void *addr, size_t len) +{ + if (likely(!ZERO_OR_NULL_PTR(addr))) { + memzero_explicit((void *)addr, len); + kvfree(addr); + } +} +EXPORT_SYMBOL(kvfree_sensitive); + static inline void *__page_rmapping(struct page *page) { unsigned long mapping; @@ -796,10 +814,6 @@ int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin) { long allowed; - VM_WARN_ONCE(percpu_counter_read(&vm_committed_as) < - -(s64)vm_committed_as_batch * num_online_cpus(), - "memory commitment underflow"); - vm_acct_memory(pages); /* |