coredump: '% at the end' shouldn't bypass core_uses_pid logic

"goto end" should not bypass the "Backward compatibility with
core_uses_pid" code, move this label up.

While at it,

	- It is ugly to copy '|' into cn->corename and then inc
	  the pointer for argv_split().

	  Change format_corename() to increment pat_ptr instead.

	- Remove the dead "if (*pat_ptr == 0)" in format_corename(),
	  we already checked it is not zero.

Signed-off-by: Oleg 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: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 7 insertions, 5 deletions

diff --git a/fs/coredump.c b/fs/coredump.c
index 56a9ab963a40..72f816d6cad9 100644
--- a/fs/coredump.c
+++ b/fs/coredump.c
@@ -165,13 +165,15 @@ static int format_corename(struct core_name *cn, struct coredump_params *cprm)
         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) {
@@ -240,6 +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)
@@ -250,7 +253,6 @@ static int format_corename(struct core_name *cn, struct coredump_params *cprm)
                 if (err)
                         return err;
         }
-out:
         return ispipe;
 }
 
@@ -580,7 +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__);
@@ -597,7 +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;
                 }