diff options
Diffstat (limited to 'fs/proc')
| -rw-r--r-- | fs/proc/Kconfig | 5 | ||||
| -rw-r--r-- | fs/proc/base.c | 163 | ||||
| -rw-r--r-- | fs/proc/inode.c | 27 | ||||
| -rw-r--r-- | fs/proc/meminfo.c | 2 | ||||
| -rw-r--r-- | fs/proc/proc_sysctl.c | 8 | ||||
| -rw-r--r-- | fs/proc/root.c | 7 | ||||
| -rw-r--r-- | fs/proc/task_mmu.c | 120 | ||||
| -rw-r--r-- | fs/proc/task_nommu.c | 6 | ||||
| -rw-r--r-- | fs/proc/vmcore.c | 9 |
9 files changed, 227 insertions, 120 deletions
diff --git a/fs/proc/Kconfig b/fs/proc/Kconfig index 4c3dcb718961..cb5629bd5fff 100644 --- a/fs/proc/Kconfig +++ b/fs/proc/Kconfig @@ -58,7 +58,8 @@ config PROC_VMCORE_DEVICE_DUMP snapshot. If you say Y here, the collected device dumps will be added - as ELF notes to /proc/vmcore. + as ELF notes to /proc/vmcore. You can still disable device + dump using the kernel command line option 'novmcoredd'. config PROC_SYSCTL bool "Sysctl support (/proc/sys)" if EXPERT @@ -72,7 +73,7 @@ config PROC_SYSCTL interface is through /proc/sys. If you say Y here a tree of modifiable sysctl entries will be generated beneath the /proc/sys directory. They are explained in the files - in <file:Documentation/sysctl/>. Note that enabling this + in <file:Documentation/admin-guide/sysctl/>. Note that enabling this option will enlarge the kernel by at least 8 KB. As it is generally a good thing, you should say Y here unless diff --git a/fs/proc/base.c b/fs/proc/base.c index c40fca98f2b7..ebea9501afb8 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -209,12 +209,53 @@ static int proc_root_link(struct dentry *dentry, struct path *path) return result; } +/* + * If the user used setproctitle(), we just get the string from + * user space at arg_start, and limit it to a maximum of one page. + */ +static ssize_t get_mm_proctitle(struct mm_struct *mm, char __user *buf, + size_t count, unsigned long pos, + unsigned long arg_start) +{ + char *page; + int ret, got; + + if (pos >= PAGE_SIZE) + return 0; + + page = (char *)__get_free_page(GFP_KERNEL); + if (!page) + return -ENOMEM; + + ret = 0; + got = access_remote_vm(mm, arg_start, page, PAGE_SIZE, FOLL_ANON); + if (got > 0) { + int len = strnlen(page, got); + + /* Include the NUL character if it was found */ + if (len < got) + len++; + + if (len > pos) { + len -= pos; + if (len > count) + len = count; + len -= copy_to_user(buf, page+pos, len); + if (!len) + len = -EFAULT; + ret = len; + } + } + free_page((unsigned long)page); + return ret; +} + static ssize_t get_mm_cmdline(struct mm_struct *mm, char __user *buf, size_t count, loff_t *ppos) { unsigned long arg_start, arg_end, env_start, env_end; unsigned long pos, len; - char *page; + char *page, c; /* Check if process spawned far enough to have cmdline. */ if (!mm->env_end) @@ -231,28 +272,42 @@ static ssize_t get_mm_cmdline(struct mm_struct *mm, char __user *buf, return 0; /* - * We have traditionally allowed the user to re-write - * the argument strings and overflow the end result - * into the environment section. But only do that if - * the environment area is contiguous to the arguments. + * We allow setproctitle() to overwrite the argument + * strings, and overflow past the original end. But + * only when it overflows into the environment area. */ - if (env_start != arg_end || env_start >= env_end) + if (env_start != arg_end || env_end < env_start) env_start = env_end = arg_end; - - /* .. and limit it to a maximum of one page of slop */ - if (env_end >= arg_end + PAGE_SIZE) - env_end = arg_end + PAGE_SIZE - 1; + len = env_end - arg_start; /* We're not going to care if "*ppos" has high bits set */ - pos = arg_start + *ppos; - - /* .. but we do check the result is in the proper range */ - if (pos < arg_start || pos >= env_end) + pos = *ppos; + if (pos >= len) + return 0; + if (count > len - pos) + count = len - pos; + if (!count) return 0; - /* .. and we never go past env_end */ - if (env_end - pos < count) - count = env_end - pos; + /* + * Magical special case: if the argv[] end byte is not + * zero, the user has overwritten it with setproctitle(3). + * + * Possible future enhancement: do this only once when + * pos is 0, and set a flag in the 'struct file'. + */ + if (access_remote_vm(mm, arg_end-1, &c, 1, FOLL_ANON) == 1 && c) + return get_mm_proctitle(mm, buf, count, pos, arg_start); + + /* + * For the non-setproctitle() case we limit things strictly + * to the [arg_start, arg_end[ range. + */ + pos += arg_start; + if (pos < arg_start || pos >= arg_end) + return 0; + if (count > arg_end - pos) + count = arg_end - pos; page = (char *)__get_free_page(GFP_KERNEL); if (!page) @@ -262,48 +317,11 @@ static ssize_t get_mm_cmdline(struct mm_struct *mm, char __user *buf, while (count) { int got; size_t size = min_t(size_t, PAGE_SIZE, count); - long offset; - /* - * Are we already starting past the official end? - * We always include the last byte that is *supposed* - * to be NUL - */ - offset = (pos >= arg_end) ? pos - arg_end + 1 : 0; - - got = access_remote_vm(mm, pos - offset, page, size + offset, FOLL_ANON); - if (got <= offset) + got = access_remote_vm(mm, pos, page, size, FOLL_ANON); + if (got <= 0) break; - got -= offset; - - /* Don't walk past a NUL character once you hit arg_end */ - if (pos + got >= arg_end) { - int n = 0; - - /* - * If we started before 'arg_end' but ended up - * at or after it, we start the NUL character - * check at arg_end-1 (where we expect the normal - * EOF to be). - * - * NOTE! This is smaller than 'got', because - * pos + got >= arg_end - */ - if (pos < arg_end) - n = arg_end - pos - 1; - - /* Cut off at first NUL after 'n' */ - got = n + strnlen(page+n, offset+got-n); - if (got < offset) - break; - got -= offset; - - /* Include the NUL if it existed */ - if (got < size) - got++; - } - - got -= copy_to_user(buf, page+offset, got); + got -= copy_to_user(buf, page, got); if (unlikely(!got)) { if (!len) len = -EFAULT; @@ -532,8 +550,7 @@ static int proc_oom_score(struct seq_file *m, struct pid_namespace *ns, unsigned long totalpages = totalram_pages() + total_swap_pages; unsigned long points = 0; - points = oom_badness(task, NULL, NULL, totalpages) * - 1000 / totalpages; + points = oom_badness(task, totalpages) * 1000 / totalpages; seq_printf(m, "%lu\n", points); return 0; @@ -1962,9 +1979,12 @@ static int map_files_d_revalidate(struct dentry *dentry, unsigned int flags) goto out; if (!dname_to_vma_addr(dentry, &vm_start, &vm_end)) { - down_read(&mm->mmap_sem); - exact_vma_exists = !!find_exact_vma(mm, vm_start, vm_end); - up_read(&mm->mmap_sem); + status = down_read_killable(&mm->mmap_sem); + if (!status) { + exact_vma_exists = !!find_exact_vma(mm, vm_start, + vm_end); + up_read(&mm->mmap_sem); + } } mmput(mm); @@ -2010,8 +2030,11 @@ static int map_files_get_link(struct dentry *dentry, struct path *path) if (rc) goto out_mmput; + rc = down_read_killable(&mm->mmap_sem); + if (rc) + goto out_mmput; + rc = -ENOENT; - down_read(&mm->mmap_sem); vma = find_exact_vma(mm, vm_start, vm_end); if (vma && vma->vm_file) { *path = vma->vm_file->f_path; @@ -2107,7 +2130,11 @@ static struct dentry *proc_map_files_lookup(struct inode *dir, if (!mm) goto out_put_task; - down_read(&mm->mmap_sem); + result = ERR_PTR(-EINTR); + if (down_read_killable(&mm->mmap_sem)) + goto out_put_mm; + + result = ERR_PTR(-ENOENT); vma = find_exact_vma(mm, vm_start, vm_end); if (!vma) goto out_no_vma; @@ -2118,6 +2145,7 @@ static struct dentry *proc_map_files_lookup(struct inode *dir, out_no_vma: up_read(&mm->mmap_sem); +out_put_mm: mmput(mm); out_put_task: put_task_struct(task); @@ -2160,7 +2188,12 @@ proc_map_files_readdir(struct file *file, struct dir_context *ctx) mm = get_task_mm(task); if (!mm) goto out_put_task; - down_read(&mm->mmap_sem); + + ret = down_read_killable(&mm->mmap_sem); + if (ret) { + mmput(mm); + goto out_put_task; + } nr_files = 0; diff --git a/fs/proc/inode.c b/fs/proc/inode.c index 5f8d215b3fd0..dbe43a50caf2 100644 --- a/fs/proc/inode.c +++ b/fs/proc/inode.c @@ -200,7 +200,8 @@ static loff_t proc_reg_llseek(struct file *file, loff_t offset, int whence) struct proc_dir_entry *pde = PDE(file_inode(file)); loff_t rv = -EINVAL; if (use_pde(pde)) { - loff_t (*llseek)(struct file *, loff_t, int); + typeof_member(struct file_operations, llseek) llseek; + llseek = pde->proc_fops->llseek; if (!llseek) llseek = default_llseek; @@ -212,10 +213,11 @@ static loff_t proc_reg_llseek(struct file *file, loff_t offset, int whence) static ssize_t proc_reg_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) { - ssize_t (*read)(struct file *, char __user *, size_t, loff_t *); struct proc_dir_entry *pde = PDE(file_inode(file)); ssize_t rv = -EIO; if (use_pde(pde)) { + typeof_member(struct file_operations, read) read; + read = pde->proc_fops->read; if (read) rv = read(file, buf, count, ppos); @@ -226,10 +228,11 @@ static ssize_t proc_reg_read(struct file *file, char __user *buf, size_t count, static ssize_t proc_reg_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) { - ssize_t (*write)(struct file *, const char __user *, size_t, loff_t *); struct proc_dir_entry *pde = PDE(file_inode(file)); ssize_t rv = -EIO; if (use_pde(pde)) { + typeof_member(struct file_operations, write) write; + write = pde->proc_fops->write; if (write) rv = write(file, buf, count, ppos); @@ -242,8 +245,9 @@ static __poll_t proc_reg_poll(struct file *file, struct poll_table_struct *pts) { struct proc_dir_entry *pde = PDE(file_inode(file)); __poll_t rv = DEFAULT_POLLMASK; - __poll_t (*poll)(struct file *, struct poll_table_struct *); if (use_pde(pde)) { + typeof_member(struct file_operations, poll) poll; + poll = pde->proc_fops->poll; if (poll) rv = poll(file, pts); @@ -256,8 +260,9 @@ static long proc_reg_unlocked_ioctl(struct file *file, unsigned int cmd, unsigne { struct proc_dir_entry *pde = PDE(file_inode(file)); long rv = -ENOTTY; - long (*ioctl)(struct file *, unsigned int, unsigned long); if (use_pde(pde)) { + typeof_member(struct file_operations, unlocked_ioctl) ioctl; + ioctl = pde->proc_fops->unlocked_ioctl; if (ioctl) rv = ioctl(file, cmd, arg); @@ -271,8 +276,9 @@ static long proc_reg_compat_ioctl(struct file *file, unsigned int cmd, unsigned { struct proc_dir_entry *pde = PDE(file_inode(file)); long rv = -ENOTTY; - long (*compat_ioctl)(struct file *, unsigned int, unsigned long); if (use_pde(pde)) { + typeof_member(struct file_operations, compat_ioctl) compat_ioctl; + compat_ioctl = pde->proc_fops->compat_ioctl; if (compat_ioctl) rv = compat_ioctl(file, cmd, arg); @@ -286,8 +292,9 @@ static int proc_reg_mmap(struct file *file, struct vm_area_struct *vma) { struct proc_dir_entry *pde = PDE(file_inode(file)); int rv = -EIO; - int (*mmap)(struct file *, struct vm_area_struct *); if (use_pde(pde)) { + typeof_member(struct file_operations, mmap) mmap; + mmap = pde->proc_fops->mmap; if (mmap) rv = mmap(file, vma); @@ -305,7 +312,7 @@ proc_reg_get_unmapped_area(struct file *file, unsigned long orig_addr, unsigned long rv = -EIO; if (use_pde(pde)) { - typeof(proc_reg_get_unmapped_area) *get_area; + typeof_member(struct file_operations, get_unmapped_area) get_area; get_area = pde->proc_fops->get_unmapped_area; #ifdef CONFIG_MMU @@ -326,8 +333,8 @@ static int proc_reg_open(struct inode *inode, struct file *file) { struct proc_dir_entry *pde = PDE(inode); int rv = 0; - int (*open)(struct inode *, struct file *); - int (*release)(struct inode *, struct file *); + typeof_member(struct file_operations, open) open; + typeof_member(struct file_operations, release) release; struct pde_opener *pdeo; /* diff --git a/fs/proc/meminfo.c b/fs/proc/meminfo.c index 568d90e17c17..465ea0153b2a 100644 --- a/fs/proc/meminfo.c +++ b/fs/proc/meminfo.c @@ -120,7 +120,7 @@ static int meminfo_proc_show(struct seq_file *m, void *v) show_val_kb(m, "Committed_AS: ", committed); seq_printf(m, "VmallocTotal: %8lu kB\n", (unsigned long)VMALLOC_TOTAL >> 10); - show_val_kb(m, "VmallocUsed: ", 0ul); + show_val_kb(m, "VmallocUsed: ", vmalloc_nr_pages()); show_val_kb(m, "VmallocChunk: ", 0ul); show_val_kb(m, "Percpu: ", pcpu_nr_pages()); diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c index c74570736b24..d80989b6c344 100644 --- a/fs/proc/proc_sysctl.c +++ b/fs/proc/proc_sysctl.c @@ -22,6 +22,10 @@ static const struct inode_operations proc_sys_inode_operations; static const struct file_operations proc_sys_dir_file_operations; static const struct inode_operations proc_sys_dir_operations; +/* shared constants to be used in various sysctls */ +const int sysctl_vals[] = { 0, 1, INT_MAX }; +EXPORT_SYMBOL(sysctl_vals); + /* Support for permanently empty directories */ struct ctl_table sysctl_mount_point[] = { @@ -499,6 +503,10 @@ static struct inode *proc_sys_make_inode(struct super_block *sb, if (root->set_ownership) root->set_ownership(head, table, &inode->i_uid, &inode->i_gid); + else { + inode->i_uid = GLOBAL_ROOT_UID; + inode->i_gid = GLOBAL_ROOT_GID; + } return inode; } diff --git a/fs/proc/root.c b/fs/proc/root.c index 522199e9525e..33f72d1b92cc 100644 --- a/fs/proc/root.c +++ b/fs/proc/root.c @@ -157,8 +157,6 @@ static int proc_get_tree(struct fs_context *fc) { struct proc_fs_context *ctx = fc->fs_private; - put_user_ns(fc->user_ns); - fc->user_ns = get_user_ns(ctx->pid_ns->user_ns); fc->s_fs_info = ctx->pid_ns; return vfs_get_super(fc, vfs_get_keyed_super, proc_fill_super); } @@ -167,8 +165,7 @@ static void proc_fs_context_free(struct fs_context *fc) { struct proc_fs_context *ctx = fc->fs_private; - if (ctx->pid_ns) - put_pid_ns(ctx->pid_ns); + put_pid_ns(ctx->pid_ns); kfree(ctx); } @@ -188,6 +185,8 @@ static int proc_init_fs_context(struct fs_context *fc) return -ENOMEM; ctx->pid_ns = get_pid_ns(task_active_pid_ns(current)); + put_user_ns(fc->user_ns); + fc->user_ns = get_user_ns(ctx->pid_ns->user_ns); fc->fs_private = ctx; fc->ops = &proc_fs_context_ops; return 0; diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index 01d4eb0e6bd1..731642e0f5a0 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -166,7 +166,11 @@ static void *m_start(struct seq_file *m, loff_t *ppos) if (!mm || !mmget_not_zero(mm)) return NULL; - down_read(&mm->mmap_sem); + if (down_read_killable(&mm->mmap_sem)) { + mmput(mm); + return ERR_PTR(-EINTR); + } + hold_task_mempolicy(priv); priv->tail_vma = get_gate_vma(mm); @@ -417,17 +421,53 @@ struct mem_size_stats { unsigned long shared_hugetlb; unsigned long private_hugetlb; u64 pss; + u64 pss_anon; + u64 pss_file; + u64 pss_shmem; u64 pss_locked; u64 swap_pss; bool check_shmem_swap; }; +static void smaps_page_accumulate(struct mem_size_stats *mss, + struct page *page, unsigned long size, unsigned long pss, + bool dirty, bool locked, bool private) +{ + mss->pss += pss; + + if (PageAnon(page)) + mss->pss_anon += pss; + else if (PageSwapBacked(page)) + mss->pss_shmem += pss; + else + mss->pss_file += pss; + + if (locked) + mss->pss_locked += pss; + + if (dirty || PageDirty(page)) { + if (private) + mss->private_dirty += size; + else + mss->shared_dirty += size; + } else { + if (private) + mss->private_clean += size; + else + mss->shared_clean += size; + } +} + static void smaps_account(struct mem_size_stats *mss, struct page *page, bool compound, bool young, bool dirty, bool locked) { int i, nr = compound ? 1 << compound_order(page) : 1; unsigned long size = nr * PAGE_SIZE; + /* + * First accumulate quantities that depend only on |size| and the type + * of the compound page. + */ if (PageAnon(page)) { mss->anonymous += size; if (!PageSwapBacked(page) && !dirty && !PageDirty(page)) @@ -440,42 +480,25 @@ static void smaps_account(struct mem_size_stats *mss, struct page *page, mss->referenced += size; /* + * Then accumulate quantities that may depend on sharing, or that may + * differ page-by-page. + * * page_count(page) == 1 guarantees the page is mapped exactly once. * If any subpage of the compound page mapped with PTE it would elevate * page_count(). */ if (page_count(page) == 1) { - if (dirty || PageDirty(page)) - mss->private_dirty += size; - else - mss->private_clean += size; - mss->pss += (u64)size << PSS_SHIFT; - if (locked) - mss->pss_locked += (u64)size << PSS_SHIFT; + smaps_page_accumulate(mss, page, size, size << PSS_SHIFT, dirty, + locked, true); return; } - for (i = 0; i < nr; i++, page++) { int mapcount = page_mapcount(page); - unsigned long pss = (PAGE_SIZE << PSS_SHIFT); - - if (mapcount >= 2) { - if (dirty || PageDirty(page)) - mss->shared_dirty += PAGE_SIZE; - else - mss->shared_clean += PAGE_SIZE; - mss->pss += pss / mapcount; - if (locked) - mss->pss_locked += pss / mapcount; - } else { - if (dirty || PageDirty(page)) - mss->private_dirty += PAGE_SIZE; - else - mss->private_clean += PAGE_SIZE; - mss->pss += pss; - if (locked) - mss->pss_locked += pss; - } + unsigned long pss = PAGE_SIZE << PSS_SHIFT; + if (mapcount >= 2) + pss /= mapcount; + smaps_page_accumulate(mss, page, PAGE_SIZE, pss, dirty, locked, + mapcount < 2); } } @@ -754,10 +777,23 @@ static void smap_gather_stats(struct vm_area_struct *vma, seq_put_decimal_ull_width(m, str, (val) >> 10, 8) /* Show the contents common for smaps and smaps_rollup */ -static void __show_smap(struct seq_file *m, const struct mem_size_stats *mss) +static void __show_smap(struct seq_file *m, const struct mem_size_stats *mss, + bool rollup_mode) { SEQ_PUT_DEC("Rss: ", mss->resident); SEQ_PUT_DEC(" kB\nPss: ", mss->pss >> PSS_SHIFT); + if (rollup_mode) { + /* + * These are meaningful only for smaps_rollup, otherwise two of + * them are zero, and the other one is the same as Pss. + */ + SEQ_PUT_DEC(" kB\nPss_Anon: ", + mss->pss_anon >> PSS_SHIFT); + SEQ_PUT_DEC(" kB\nPss_File: ", + mss->pss_file >> PSS_SHIFT); + SEQ_PUT_DEC(" kB\nPss_Shmem: ", + mss->pss_shmem >> PSS_SHIFT); + } SEQ_PUT_DEC(" kB\nShared_Clean: ", mss->shared_clean); SEQ_PUT_DEC(" kB\nShared_Dirty: ", mss->shared_dirty); SEQ_PUT_DEC(" kB\nPrivate_Clean: ", mss->private_clean); @@ -794,9 +830,10 @@ static int show_smap(struct seq_file *m, void *v) SEQ_PUT_DEC(" kB\nMMUPageSize: ", vma_mmu_pagesize(vma)); seq_puts(m, " kB\n"); - __show_smap(m, &mss); + __show_smap(m, &mss, false); - seq_printf(m, "THPeligible: %d\n", transparent_hugepage_enabled(vma)); + seq_printf(m, "THPeligible: %d\n", + transparent_hugepage_enabled(vma)); if (arch_pkeys_enabled()) seq_printf(m, "ProtectionKey: %8u\n", vma_pkey(vma)); @@ -828,7 +865,10 @@ static int show_smaps_rollup(struct seq_file *m, void *v) memset(&mss, 0, sizeof(mss)); - down_read(&mm->mmap_sem); + ret = down_read_killable(&mm->mmap_sem); + if (ret) + goto out_put_mm; + hold_task_mempolicy(priv); for (vma = priv->mm->mmap; vma; vma = vma->vm_next) { @@ -841,12 +881,13 @@ static int show_smaps_rollup(struct seq_file *m, void *v) seq_pad(m, ' '); seq_puts(m, "[rollup]\n"); - __show_smap(m, &mss); + __show_smap(m, &mss, true); release_task_mempolicy(priv); up_read(&mm->mmap_sem); - mmput(mm); +out_put_mm: + mmput(mm); out_put_task: put_task_struct(priv->task); priv->task = NULL; @@ -1132,7 +1173,10 @@ static ssize_t clear_refs_write(struct file *file, const char __user *buf, goto out_mm; } - down_read(&mm->mmap_sem); + if (down_read_killable(&mm->mmap_sem)) { + count = -EINTR; + goto out_mm; + } tlb_gather_mmu(&tlb, mm, 0, -1); if (type == CLEAR_REFS_SOFT_DIRTY) { for (vma = mm->mmap; vma; vma = vma->vm_next) { @@ -1279,7 +1323,7 @@ static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm, if (pm->show_pfn) frame = pte_pfn(pte); flags |= PM_PRESENT; - page = _vm_normal_page(vma, addr, pte, true); + page = vm_normal_page(vma, addr, pte); if (pte_soft_dirty(pte)) flags |= PM_SOFT_DIRTY; } else if (is_swap_pte(pte)) { @@ -1539,7 +1583,9 @@ static ssize_t pagemap_read(struct file *file, char __user *buf, /* overflow ? */ if (end < start_vaddr || end > end_vaddr) end = end_vaddr; - down_read(&mm->mmap_sem); + ret = down_read_killable(&mm->mmap_sem); + if (ret) + goto out_free; ret = walk_page_range(start_vaddr, end, &pagemap_walk); up_read(&mm->mmap_sem); start_vaddr = end; diff --git a/fs/proc/task_nommu.c b/fs/proc/task_nommu.c index 36bf0f2e102e..7907e6419e57 100644 --- a/fs/proc/task_nommu.c +++ b/fs/proc/task_nommu.c @@ -211,7 +211,11 @@ static void *m_start(struct seq_file *m, loff_t *pos) if (!mm || !mmget_not_zero(mm)) return NULL; - down_read(&mm->mmap_sem); + if (down_read_killable(&mm->mmap_sem)) { + mmput(mm); + return ERR_PTR(-EINTR); + } + /* start from the Nth VMA */ for (p = rb_first(&mm->mm_rb); p; p = rb_next(p)) if (n-- == 0) diff --git a/fs/proc/vmcore.c b/fs/proc/vmcore.c index 57957c91c6df..7bcc92add72c 100644 --- a/fs/proc/vmcore.c +++ b/fs/proc/vmcore.c @@ -21,6 +21,7 @@ #include <linux/init.h> #include <linux/crash_dump.h> #include <linux/list.h> +#include <linux/moduleparam.h> #include <linux/mutex.h> #include <linux/vmalloc.h> #include <linux/pagemap.h> @@ -54,6 +55,9 @@ static struct proc_dir_entry *proc_vmcore; /* Device Dump list and mutex to synchronize access to list */ static LIST_HEAD(vmcoredd_list); static DEFINE_MUTEX(vmcoredd_mutex); + +static bool vmcoredd_disabled; +core_param(novmcoredd, vmcoredd_disabled, bool, 0); #endif /* CONFIG_PROC_VMCORE_DEVICE_DUMP */ /* Device Dump Size */ @@ -1452,6 +1456,11 @@ int vmcore_add_device_dump(struct vmcoredd_data *data) size_t data_size; int ret; + if (vmcoredd_disabled) { + pr_err_once("Device dump is disabled\n"); + return -EINVAL; + } + if (!data || !strlen(data->dump_name) || !data->vmcoredd_callback || !data->size) return -EINVAL; |
