Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 923bed03 authored by Oleg Nesterov's avatar Oleg Nesterov Committed by Linus Torvalds
Browse files

coredump: kill cn_escape(), introduce cn_esc_printf() 



The usage of cn_escape() looks really annoying, imho this sequence needs a
wrapper.  And it is buggy.  If cn_printf() does expand_corename()
cn_escape() writes to the freed memory.

Introduce cn_esc_printf() which hopefully does this all right.  It records
the index before cn_vprintf(), not "char *" which is no longer valid (in
general) after krealloc().

Signed-off-by: default avatarOleg Nesterov <oleg@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Colin Walters <walters@verbum.org>
Cc: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Lennart Poettering <mzxreary@0pointer.de>
Cc: Lucas De Marchi <lucas.de.marchi@gmail.com>
Acked-by: default avatarNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 5fe9d8ca

fs/coredump.c

+21 −23
Original line number Diff line number Diff line
@@ -99,11 +99,21 @@ static int cn_printf(struct core_name *cn, const char *fmt, ...) 
	return ret;

}



static void cn_escape(char *str)

static int cn_esc_printf(struct core_name *cn, const char *fmt, ...)

{

	for (; *str; str++)

		if (*str == '/')

			*str = '!';

	int cur = cn->used;

	va_list arg;

	int ret;



	va_start(arg, fmt);

	ret = cn_vprintf(cn, fmt, arg);

	va_end(arg);



	for (; cur < cn->used; ++cur) {

		if (cn->corename[cur] == '/')

			cn->corename[cur] = '!';

	}

	return ret;

}



static int cn_print_exe_file(struct core_name *cn)
@@ -113,12 +123,8 @@ 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) {
@@ -132,9 +138,7 @@ 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);
@@ -207,22 +211,16 @@ 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;