X-Git-Url: https://git.karo-electronics.de/?a=blobdiff_plain;f=fs%2Fcoredump.c;h=72f816d6cad99d4d1f81433e928d42e540295188;hb=393e661d6167c1b7444704191ea1d01aa3447894;hp=dafafbafa7313e2e7ef46d05619482b2edf5645d;hpb=05a88a43604abb816dfbff075bb114224641793b;p=karo-tx-linux.git diff --git a/fs/coredump.c b/fs/coredump.c index dafafbafa731..72f816d6cad9 100644 --- a/fs/coredump.c +++ b/fs/coredump.c @@ -45,69 +45,79 @@ #include int core_uses_pid; -char core_pattern[CORENAME_MAX_SIZE] = "core"; unsigned int core_pipe_limit; +char core_pattern[CORENAME_MAX_SIZE] = "core"; +static int core_name_size = CORENAME_MAX_SIZE; struct core_name { char *corename; int used, size; }; -static atomic_t call_count = ATOMIC_INIT(1); /* The maximal length of core_pattern is also specified in sysctl.c */ -static int expand_corename(struct core_name *cn) +static int expand_corename(struct core_name *cn, int size) { - char *old_corename = cn->corename; - - cn->size = CORENAME_MAX_SIZE * atomic_inc_return(&call_count); - cn->corename = krealloc(old_corename, cn->size, GFP_KERNEL); + char *corename = krealloc(cn->corename, size, GFP_KERNEL); - if (!cn->corename) { - kfree(old_corename); + if (!corename) return -ENOMEM; - } + if (size > core_name_size) /* racy but harmless */ + core_name_size = size; + + cn->size = ksize(corename); + cn->corename = corename; return 0; } +static int cn_vprintf(struct core_name *cn, const char *fmt, va_list arg) +{ + int free, need; + +again: + free = cn->size - cn->used; + need = vsnprintf(cn->corename + cn->used, free, fmt, arg); + if (need < free) { + cn->used += need; + return 0; + } + + if (!expand_corename(cn, cn->size + need - free + 1)) + goto again; + + return -ENOMEM; +} + static int cn_printf(struct core_name *cn, const char *fmt, ...) { - char *cur; - int need; - int ret; va_list arg; + int ret; va_start(arg, fmt); - need = vsnprintf(NULL, 0, fmt, arg); + ret = cn_vprintf(cn, fmt, arg); va_end(arg); - if (likely(need < cn->size - cn->used - 1)) - goto out_printf; + return ret; +} - ret = expand_corename(cn); - if (ret) - goto expand_fail; +static int cn_esc_printf(struct core_name *cn, const char *fmt, ...) +{ + int cur = cn->used; + va_list arg; + int ret; -out_printf: - cur = cn->corename + cn->used; va_start(arg, fmt); - vsnprintf(cur, need + 1, fmt, arg); + ret = cn_vprintf(cn, fmt, arg); va_end(arg); - cn->used += need; - return 0; -expand_fail: + for (; cur < cn->used; ++cur) { + if (cn->corename[cur] == '/') + cn->corename[cur] = '!'; + } return ret; } -static void cn_escape(char *str) -{ - for (; *str; str++) - if (*str == '/') - *str = '!'; -} - static int cn_print_exe_file(struct core_name *cn) { struct file *exe_file; @@ -115,12 +125,8 @@ static int cn_print_exe_file(struct core_name *cn) int ret; exe_file = get_mm_exe_file(current->mm); - if (!exe_file) { - char *commstart = cn->corename + cn->used; - ret = cn_printf(cn, "%s (path unknown)", current->comm); - cn_escape(commstart); - return ret; - } + if (!exe_file) + return cn_esc_printf(cn, "%s (path unknown)", current->comm); pathbuf = kmalloc(PATH_MAX, GFP_TEMPORARY); if (!pathbuf) { @@ -134,9 +140,7 @@ static int cn_print_exe_file(struct core_name *cn) goto free_buf; } - cn_escape(path); - - ret = cn_printf(cn, "%s", path); + ret = cn_esc_printf(cn, "%s", path); free_buf: kfree(pathbuf); @@ -157,19 +161,19 @@ static int format_corename(struct core_name *cn, struct coredump_params *cprm) int pid_in_pattern = 0; int err = 0; - cn->size = CORENAME_MAX_SIZE * atomic_read(&call_count); - cn->corename = kmalloc(cn->size, GFP_KERNEL); cn->used = 0; - - if (!cn->corename) + cn->corename = NULL; + if (expand_corename(cn, core_name_size)) return -ENOMEM; + cn->corename[0] = '\0'; + + if (ispipe) + ++pat_ptr; /* Repeat as long as we have more pattern to process and more output space */ while (*pat_ptr) { if (*pat_ptr != '%') { - if (*pat_ptr == 0) - goto out; err = cn_printf(cn, "%c", *pat_ptr++); } else { switch (*++pat_ptr) { @@ -210,22 +214,16 @@ static int format_corename(struct core_name *cn, struct coredump_params *cprm) break; } /* hostname */ - case 'h': { - char *namestart = cn->corename + cn->used; + case 'h': down_read(&uts_sem); - err = cn_printf(cn, "%s", + err = cn_esc_printf(cn, "%s", utsname()->nodename); up_read(&uts_sem); - cn_escape(namestart); break; - } /* executable */ - case 'e': { - char *commstart = cn->corename + cn->used; - err = cn_printf(cn, "%s", current->comm); - cn_escape(commstart); + case 'e': + err = cn_esc_printf(cn, "%s", current->comm); break; - } case 'E': err = cn_print_exe_file(cn); break; @@ -244,6 +242,7 @@ static int format_corename(struct core_name *cn, struct coredump_params *cprm) return err; } +out: /* Backward compatibility with core_uses_pid: * * If core_pattern does not include a %p (as is the default) @@ -254,7 +253,6 @@ static int format_corename(struct core_name *cn, struct coredump_params *cprm) if (err) return err; } -out: return ispipe; } @@ -549,7 +547,7 @@ void do_coredump(siginfo_t *siginfo) if (ispipe < 0) { printk(KERN_WARNING "format_corename failed\n"); printk(KERN_WARNING "Aborting core\n"); - goto fail_corename; + goto fail_unlock; } if (cprm.limit == 1) { @@ -584,7 +582,7 @@ void do_coredump(siginfo_t *siginfo) goto fail_dropcount; } - helper_argv = argv_split(GFP_KERNEL, cn.corename+1, NULL); + helper_argv = argv_split(GFP_KERNEL, cn.corename, NULL); if (!helper_argv) { printk(KERN_WARNING "%s failed to allocate memory\n", __func__); @@ -601,7 +599,7 @@ void do_coredump(siginfo_t *siginfo) argv_free(helper_argv); if (retval) { - printk(KERN_INFO "Core dump to %s pipe failed\n", + printk(KERN_INFO "Core dump to |%s pipe failed\n", cn.corename); goto close_fail; } @@ -669,7 +667,6 @@ fail_dropcount: atomic_dec(&core_dump_count); fail_unlock: kfree(cn.corename); -fail_corename: coredump_finish(mm, core_dumped); revert_creds(old_cred); fail_creds: