Hello, t...@!
The getmntinfo(3) page says that the mentioned function uses static
storage which cannot be freed, however this storage is being actually
malloced and can be freed without consequences.
I see no real need in doing such weird things (correct me if i'm
wrong) so here's a diff to actually do pass a singly-malloced buffer
to the caller who should free it manually.
I've also converted the essential users of that function:
bin/df sbin/mount sbin/umount sbin/mountd usr.bin/fstat.
If you find this approach good/useful I'll convert the rest (the
manpage will also need some love).
It is good to subsequently replace all static stuff in libc, right?
Index: getmntinfo.c
===================================================================
RCS file: /cvs/src/lib/libc/gen/getmntinfo.c,v
retrieving revision 1.7
diff -u -p -r1.7 getmntinfo.c
--- getmntinfo.c 8 Aug 2005 08:05:34 -0000 1.7
+++ getmntinfo.c 14 Oct 2010 22:28:06 -0000
@@ -38,25 +38,22 @@
int
getmntinfo(struct statfs **mntbufp, int flags)
{
- static struct statfs *mntbuf;
- static int mntsize;
- static size_t bufsize;
+ struct statfs *mntbuf;
+ int mntsize;
+ size_t bufsize = 0;
- if (mntsize <= 0 && (mntsize = getfsstat(0, 0, MNT_NOWAIT)) < 0)
+ if ((mntsize = getfsstat(NULL, 0, MNT_NOWAIT)) < 0)
return (0);
- if (bufsize > 0 && (mntsize = getfsstat(mntbuf, bufsize, flags)) < 0)
+
+ bufsize = mntsize * sizeof(struct statfs);
+ if ((mntbuf = malloc(bufsize)) == NULL)
+ return (0);
+
+ if ((mntsize = getfsstat(mntbuf, bufsize, flags)) < 0) {
+ free(mntbuf);
return (0);
- while (bufsize <= mntsize * sizeof(struct statfs)) {
- if (mntbuf)
- free(mntbuf);
- bufsize = (mntsize + 1) * sizeof(struct statfs);
- if ((mntbuf = (struct statfs *)malloc(bufsize)) == 0) {
- bufsize = 0;
- return (0);
- }
- if ((mntsize = getfsstat(mntbuf, bufsize, flags)) < 0)
- return (0);
}
+
*mntbufp = mntbuf;
return (mntsize);
}
Index: bin/df/df.c
===================================================================
RCS file: /cvs/src/bin/df/df.c,v
retrieving revision 1.50
diff -u -p -r1.50 df.c
--- bin/df/df.c 27 Oct 2009 23:59:21 -0000 1.50
+++ bin/df/df.c 14 Oct 2010 23:19:58 -0000
@@ -74,7 +74,7 @@ int
main(int argc, char *argv[])
{
struct stat stbuf;
- struct statfs *mntbuf;
+ struct statfs *mntbuf = NULL;
long mntsize;
int ch, i;
int width, maxwidth;
@@ -125,16 +125,19 @@ main(int argc, char *argv[])
if (!*argv) {
mntsize = regetmntinfo(&mntbuf, mntsize);
} else {
+ free(mntbuf);
mntbuf = calloc(argc, sizeof(struct statfs));
if (mntbuf == NULL)
err(1, NULL);
mntsize = 0;
for (; *argv; argv++) {
+ int freemntpt = 0;
if (stat(*argv, &stbuf) < 0) {
- if ((mntpt = getmntpt(*argv)) == 0) {
+ if ((mntpt = getmntpt(*argv)) == NULL) {
warn("%s", *argv);
continue;
}
+ freemntpt = 1;
} else if (S_ISCHR(stbuf.st_mode) ||
S_ISBLK(stbuf.st_mode)) {
if (!raw_df(*argv, &mntbuf[mntsize]))
++mntsize;
@@ -156,6 +159,9 @@ main(int argc, char *argv[])
++mntsize;
else
warn("%s", *argv);
+
+ if (freemntpt)
+ free(mntpt);
}
}
@@ -176,21 +182,26 @@ main(int argc, char *argv[])
bsdprint(mntbuf, mntsize, maxwidth);
}
- exit(mntsize ? 0 : 1);
+ free(mntbuf);
+ return (mntsize ? 0 : 1);
}
char *
getmntpt(char *name)
{
+ char *s = NULL;
long mntsize, i;
- struct statfs *mntbuf;
+ struct statfs *mntbuf = NULL;
mntsize = getmntinfo(&mntbuf, MNT_NOWAIT);
for (i = 0; i < mntsize; i++) {
- if (!strcmp(mntbuf[i].f_mntfromname, name))
- return (mntbuf[i].f_mntonname);
+ if (!strcmp(mntbuf[i].f_mntfromname, name)) {
+ s = strdup(mntbuf[i].f_mntonname);
+ break;
+ }
}
- return (0);
+ free(mntbuf);
+ return (s);
}
static enum { IN_LIST, NOT_IN_LIST } which;
@@ -257,7 +268,11 @@ regetmntinfo(struct statfs **mntbufp, lo
struct statfs *mntbuf;
if (!lflag && typelist == NULL)
- return (nflag ? mntsize : getmntinfo(mntbufp, MNT_WAIT));
+ if (!nflag) {
+ free(*mntbufp);
+ return (getmntinfo(mntbufp, MNT_WAIT));
+ } else
+ return (mntsize);
mntbuf = *mntbufp;
j = 0;
Index: sbin/mount/mount.c
===================================================================
RCS file: /cvs/src/sbin/mount/mount.c,v
retrieving revision 1.50
diff -u -p -r1.50 mount.c
--- sbin/mount/mount.c 27 Oct 2009 23:59:33 -0000 1.50
+++ sbin/mount/mount.c 14 Oct 2010 23:19:58 -0000
@@ -59,7 +59,7 @@ int selected(const char *);
char *catopt(char *, const char *);
char *flags2opts(u_int32_t);
struct statfs
- *getmntpt(const char *);
+ *getmntpt(struct statfs *, int, const char *);
int hasopt(const char *, const char *);
void maketypelist(char *);
void mangle(char *, int *, const char **, int);
@@ -100,7 +100,7 @@ int
main(int argc, char * const argv[])
{
const char *mntonname, *vfstype;
- struct fstab *fs;
+ struct fstab *fs, *fsa = NULL;
struct statfs *mntbuf;
FILE *mountdfp;
pid_t pid;
@@ -194,6 +194,7 @@ main(int argc, char * const argv[])
continue;
prmount(&mntbuf[i]);
}
+ free(mntbuf);
exit(rval);
}
break;
@@ -204,32 +205,37 @@ main(int argc, char * const argv[])
if (realpath(*argv, mntpath) == NULL)
err(1, "realpath %s", *argv);
if (hasopt(options, "update")) {
- if ((mntbuf = getmntpt(mntpath)) == NULL)
+ struct statfs *mntpt;
+
+ if ((mntsize = getmntinfo(&mntbuf, MNT_NOWAIT)) == 0)
+ err(1, "getmntinfo");
+
+ if ((mntpt = getmntpt(mntbuf, mntsize, mntpath)) ==
NULL)
errx(1,
"unknown special file or file system %s.",
*argv);
- if ((mntbuf->f_flags & MNT_ROOTFS) &&
- !strcmp(mntbuf->f_mntfromname, "root_device")) {
+ if ((mntpt->f_flags & MNT_ROOTFS) &&
+ !strcmp(mntpt->f_mntfromname, "root_device")) {
/* Lookup fstab for name of root device. */
- fs = getfsfile(mntbuf->f_mntonname);
+ fs = getfsfile(mntpt->f_mntonname);
if (fs == NULL)
errx(1,
"can't find fstab entry for %s.",
*argv);
} else {
- fs = malloc(sizeof(*fs));
+ fsa = fs = malloc(sizeof(*fs));
if (fs == NULL)
err(1, "malloc");
- fs->fs_vfstype = mntbuf->f_fstypename;
- fs->fs_spec = mntbuf->f_mntfromname;
+ fs->fs_vfstype = mntpt->f_fstypename;
+ fs->fs_spec = mntpt->f_mntfromname;
}
/*
* It's an update, ignore the fstab file options.
* Get the current options, so we can change only
* the options which given via a command line.
*/
- fs->fs_mntops = flags2opts(mntbuf->f_flags);
- mntonname = mntbuf->f_mntonname;
+ fs->fs_mntops = flags2opts(mntpt->f_flags);
+ mntonname = mntpt->f_mntonname;
} else {
if ((fs = getfsfile(mntpath)) == NULL &&
(fs = getfsspec(mntpath)) == NULL)
@@ -280,7 +286,9 @@ main(int argc, char * const argv[])
(void)fclose(mountdfp);
}
- exit(rval);
+ free(fsa);
+ free(mntbuf);
+ return (rval);
}
int
@@ -584,12 +592,10 @@ prmount(struct statfs *sf)
}
struct statfs *
-getmntpt(const char *name)
+getmntpt(struct statfs *mntbuf, int mntsize, const char *name)
{
- struct statfs *mntbuf;
- int i, mntsize;
+ int i;
- mntsize = getmntinfo(&mntbuf, MNT_NOWAIT);
for (i = 0; i < mntsize; i++)
if (strcmp(mntbuf[i].f_mntfromname, name) == 0 ||
strcmp(mntbuf[i].f_mntonname, name) == 0)
Index: sbin/umount/umount.c
===================================================================
RCS file: /cvs/src/sbin/umount/umount.c,v
retrieving revision 1.21
diff -u -p -r1.21 umount.c
--- sbin/umount/umount.c 27 Oct 2009 23:59:34 -0000 1.21
+++ sbin/umount/umount.c 14 Oct 2010 23:19:58 -0000
@@ -119,7 +119,7 @@ main(int argc, char *argv[])
int
umountall(void)
{
- struct statfs *fs;
+ struct statfs *fs = NULL;
int n;
int rval;
@@ -137,6 +137,7 @@ umountall(void)
if (umountfs(fs[n].f_mntonname))
rval = 1;
}
+ free(fs);
return (rval);
}
@@ -164,6 +165,7 @@ umountfs(char *oname)
if (S_ISBLK(sb.st_mode)) {
if ((mntpt = getmntname(name, MNTON, type)) == NULL) {
warnx("%s: not currently mounted", name);
+ free(mntpt);
return (1);
}
} else if (!S_ISDIR(sb.st_mode)) {
@@ -177,9 +179,9 @@ umountfs(char *oname)
* 99.9% of the time the path in the kernel is the one
* realpath() returns but check the original just in case...
*/
+ newname = mntpt = NULL;
if (!(newname = getmntname(name, MNTFROM, type)) &&
!(mntpt = getmntname(name, MNTON, type)) ) {
- mntpt = oname;
if (!(newname = getmntname(oname, MNTFROM, type)) &&
!(mntpt = getmntname(oname, MNTON, type))) {
warnx("%s: not currently mounted", oname);
@@ -245,13 +247,16 @@ umountfs(char *oname)
auth_destroy(clp->cl_auth);
clnt_destroy(clp);
}
+ free(mntpt);
+ free(newname);
return (0);
}
char *
getmntname(char *name, mntwhat what, char *type)
{
- struct statfs *mntbuf;
+ char *mntname = NULL;
+ struct statfs *mntbuf = NULL;
int i, mntsize;
if ((mntsize = getmntinfo(&mntbuf, MNT_NOWAIT)) == 0) {
@@ -263,16 +268,19 @@ getmntname(char *name, mntwhat what, cha
if (type)
memcpy(type, mntbuf[i].f_fstypename,
sizeof(mntbuf[i].f_fstypename));
- return (mntbuf[i].f_mntonname);
+ mntname = strdup(mntbuf[i].f_mntonname);
+ break;
}
if ((what == MNTFROM) && !strcmp(mntbuf[i].f_mntonname, name)) {
if (type)
memcpy(type, mntbuf[i].f_fstypename,
sizeof(mntbuf[i].f_fstypename));
- return (mntbuf[i].f_mntfromname);
+ mntname = strdup(mntbuf[i].f_mntfromname);
+ break;
}
}
- return (NULL);
+ free(mntbuf);
+ return (mntname);
}
static enum { IN_LIST, NOT_IN_LIST } which;
Index: sbin/mountd/mountd.c
===================================================================
RCS file: /cvs/src/sbin/mountd/mountd.c,v
retrieving revision 1.71
diff -u -p -r1.71 mountd.c
--- sbin/mountd/mountd.c 22 Mar 2010 16:35:27 -0000 1.71
+++ sbin/mountd/mountd.c 14 Oct 2010 23:19:58 -0000
@@ -688,7 +688,7 @@ get_exportlist(void)
struct grouplist *grp, *tgrp;
struct exportlist **epp;
struct dirlist *dirhead;
- struct statfs fsb, *ofsp, *fsp;
+ struct statfs fsb, *ofsp = NULL, *fsp;
struct hostent *hpe;
struct ucred anon;
union {
@@ -738,7 +738,6 @@ get_exportlist(void)
out_of_mem();
for (i = 0; i < num; i++) {
-
if (!strncmp(fsp->f_fstypename, MOUNT_MFS, MFSNAMELEN) ||
!strncmp(fsp->f_fstypename, MOUNT_FFS, MFSNAMELEN) ||
!strncmp(fsp->f_fstypename, MOUNT_EXT2FS, MFSNAMELEN) ||
@@ -1047,8 +1046,9 @@ nextline:
syslog(LOG_ERR, "Can't delete exports for %s: %m",
fsp->f_mntonname);
}
- free(fstbl);
fclose(exp_file);
+ free(fstbl);
+ free(ofsp);
}
/*
Index: usr.bin/fstat/fstat.c
===================================================================
RCS file: /cvs/src/usr.bin/fstat/fstat.c,v
retrieving revision 1.70
diff -u -p -r1.70 fstat.c
--- usr.bin/fstat/fstat.c 27 Oct 2009 23:59:38 -0000 1.70
+++ usr.bin/fstat/fstat.c 14 Oct 2010 23:19:58 -0000
@@ -100,6 +100,7 @@ int signo; /* signal to send (fuser onl
kvm_t *kd;
uid_t uid;
+static struct statfs *mntbuf;
void fstat_dofile(struct kinfo_file2 *);
void fstat_header(void);
@@ -266,7 +267,8 @@ main(int argc, char *argv[])
if (fuser)
fuser_run();
- exit(0);
+ free(mntbuf);
+ return (0);
}
void
@@ -737,7 +739,6 @@ getinetproto(number)
int
getfname(char *filename)
{
- static struct statfs *mntbuf;
static int nmounts;
int i;
struct stat sb;
@@ -757,7 +758,7 @@ getfname(char *filename)
if (fuser && !fsflg && S_ISBLK(sb.st_mode)) {
if (mntbuf == NULL) {
nmounts = getmntinfo(&mntbuf, MNT_NOWAIT);
- if (nmounts == -1)
+ if (nmounts == 0)
err(1, "getmntinfo");
}
for (i = 0; i < nmounts; i++) {
