| Message ID | 1425646817-20100-1-git-send-email-nicolas.iooss_linux@m4x.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Ping? Comments (or NACK or ACK) would be greatly appreciated on this patch. Of course, if you prefer to use init_user_ns instead of cred->user_ns, I can send an other patch. Nicolas On 03/06/2015 09:00 PM, Nicolas Iooss wrote: > 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> > --- > fs/coredump.c | 18 ++++++++++++------ > 1 file changed, 12 insertions(+), 6 deletions(-) > > diff --git a/fs/coredump.c b/fs/coredump.c > index f319926ddf8c..762d827825a8 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': { > -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/coredump.c b/fs/coredump.c index f319926ddf8c..762d827825a8 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': {
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> --- fs/coredump.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-)