lkml.org 
[lkml]   [2015]   [Apr]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH RESENT] coredump: fix cn_printf formatting warnings
Date
Add __printf attributes to cn_*printf functions.  With these, gcc says:

fs/coredump.c:213:5: warning: format '%d' expects argument of type
'int', but argument 3 has type 'kuid_t' [-Wformat=]
err = cn_printf(cn, "%d", cred->uid);
^
fs/coredump.c:217:5: warning: format '%d' expects argument of type
'int', but argument 3 has type 'kgid_t' [-Wformat=]
err = cn_printf(cn, "%d", cred->gid);
^
fs/coredump.c:225:5: warning: format '%ld' expects argument of type
'long int', but argument 3 has type 'int' [-Wformat=]
err = cn_printf(cn, "%ld", cprm->siginfo->si_signo);
^

The third warning is easily fixed as si_signo is always an int.

For the two others, cred->uid and cred->gid need to be converted to
either a user-namespace UID/GID or to init_user_ns UID/GID. As
Documentation/sysctl/kernel.txt does not specify which user namespace is
used to translate %u and %g in core_pattern, but lowercase %p and %i are
used to format pid/tid in current process namespace, it seems intuitive
that lowercase %u and %g use the current user namespace. So implement
this.

Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
---

I sent this patch more than a month ago but go no feedback, so I'm sending it again.
Comments would be greatly appreciated.

fs/coredump.c | 18 ++++++++++++------
1 file changed, 12 insertions(+), 6 deletions(-)

diff --git a/fs/coredump.c b/fs/coredump.c
index bbbe139ab280..977fc8b91f2d 100644
--- a/fs/coredump.c
+++ b/fs/coredump.c
@@ -70,7 +70,8 @@ static int expand_corename(struct core_name *cn, int size)
return 0;
}

-static int cn_vprintf(struct core_name *cn, const char *fmt, va_list arg)
+static __printf(2, 0) int cn_vprintf(struct core_name *cn, const char *fmt,
+ va_list arg)
{
int free, need;
va_list arg_copy;
@@ -93,7 +94,7 @@ again:
return -ENOMEM;
}

-static int cn_printf(struct core_name *cn, const char *fmt, ...)
+static __printf(2, 3) int cn_printf(struct core_name *cn, const char *fmt, ...)
{
va_list arg;
int ret;
@@ -105,7 +106,8 @@ static int cn_printf(struct core_name *cn, const char *fmt, ...)
return ret;
}

-static int cn_esc_printf(struct core_name *cn, const char *fmt, ...)
+static __printf(2, 3)
+int cn_esc_printf(struct core_name *cn, const char *fmt, ...)
{
int cur = cn->used;
va_list arg;
@@ -209,11 +211,15 @@ static int format_corename(struct core_name *cn, struct coredump_params *cprm)
break;
/* uid */
case 'u':
- err = cn_printf(cn, "%d", cred->uid);
+ err = cn_printf(cn, "%d",
+ from_kuid_munged(cred->user_ns,
+ cred->uid));
break;
/* gid */
case 'g':
- err = cn_printf(cn, "%d", cred->gid);
+ err = cn_printf(cn, "%d",
+ from_kgid_munged(cred->user_ns,
+ cred->gid));
break;
case 'd':
err = cn_printf(cn, "%d",
@@ -221,7 +227,7 @@ static int format_corename(struct core_name *cn, struct coredump_params *cprm)
break;
/* signal that caused the coredump */
case 's':
- err = cn_printf(cn, "%ld", cprm->siginfo->si_signo);
+ err = cn_printf(cn, "%d", cprm->siginfo->si_signo);
break;
/* UNIX time of coredump */
case 't': {
--
2.3.5


\
 
 \ /
  Last update: 2015-04-16 13:01    [W:0.092 / U:0.048 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site