diff options
Diffstat (limited to 'fs/coredump.c')
| -rw-r--r-- | fs/coredump.c | 59 |
1 files changed, 49 insertions, 10 deletions
diff --git a/fs/coredump.c b/fs/coredump.c index d48edb37bc35..c33c177a701b 100644 --- a/fs/coredump.c +++ b/fs/coredump.c @@ -63,6 +63,7 @@ static void free_vma_snapshot(struct coredump_params *cprm); static int core_uses_pid; static unsigned int core_pipe_limit; +static unsigned int core_sort_vma; static char core_pattern[CORENAME_MAX_SIZE] = "core"; static int core_name_size = CORENAME_MAX_SIZE; unsigned int core_file_note_size_limit = CORE_FILE_NOTE_SIZE_DEFAULT; @@ -925,14 +926,23 @@ int dump_user_range(struct coredump_params *cprm, unsigned long start, { unsigned long addr; struct page *dump_page; + int locked, ret; dump_page = dump_page_alloc(); if (!dump_page) return 0; + ret = 0; + locked = 0; for (addr = start; addr < start + len; addr += PAGE_SIZE) { struct page *page; + if (!locked) { + if (mmap_read_lock_killable(current->mm)) + goto out; + locked = 1; + } + /* * To avoid having to allocate page tables for virtual address * ranges that have never been used yet, and also to make it @@ -940,21 +950,38 @@ int dump_user_range(struct coredump_params *cprm, unsigned long start, * NULL when encountering an empty page table entry that would * otherwise have been filled with the zero page. */ - page = get_dump_page(addr); + page = get_dump_page(addr, &locked); if (page) { + if (locked) { + mmap_read_unlock(current->mm); + locked = 0; + } int stop = !dump_emit_page(cprm, dump_page_copy(page, dump_page)); put_page(page); - if (stop) { - dump_page_free(dump_page); - return 0; - } + if (stop) + goto out; } else { dump_skip(cprm, PAGE_SIZE); } + + if (dump_interrupted()) + goto out; + + if (!need_resched()) + continue; + if (locked) { + mmap_read_unlock(current->mm); + locked = 0; + } cond_resched(); } + ret = 1; +out: + if (locked) + mmap_read_unlock(current->mm); + dump_page_free(dump_page); - return 1; + return ret; } #endif @@ -995,7 +1022,7 @@ static int proc_dostring_coredump(const struct ctl_table *table, int write, static const unsigned int core_file_note_size_min = CORE_FILE_NOTE_SIZE_DEFAULT; static const unsigned int core_file_note_size_max = CORE_FILE_NOTE_SIZE_MAX; -static struct ctl_table coredump_sysctls[] = { +static const struct ctl_table coredump_sysctls[] = { { .procname = "core_uses_pid", .data = &core_uses_pid, @@ -1015,7 +1042,9 @@ static struct ctl_table coredump_sysctls[] = { .data = &core_pipe_limit, .maxlen = sizeof(unsigned int), .mode = 0644, - .proc_handler = proc_dointvec, + .proc_handler = proc_dointvec_minmax, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_INT_MAX, }, { .procname = "core_file_note_size_limit", @@ -1026,6 +1055,15 @@ static struct ctl_table coredump_sysctls[] = { .extra1 = (unsigned int *)&core_file_note_size_min, .extra2 = (unsigned int *)&core_file_note_size_max, }, + { + .procname = "core_sort_vma", + .data = &core_sort_vma, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_douintvec_minmax, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_ONE, + }, }; static int __init init_fs_coredump_sysctls(void) @@ -1256,8 +1294,9 @@ static bool dump_vma_snapshot(struct coredump_params *cprm) cprm->vma_data_size += m->dump_size; } - sort(cprm->vma_meta, cprm->vma_count, sizeof(*cprm->vma_meta), - cmp_vma_size, NULL); + if (core_sort_vma) + sort(cprm->vma_meta, cprm->vma_count, sizeof(*cprm->vma_meta), + cmp_vma_size, NULL); return true; } |