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ape: fix memory leak and path limit in unlink()

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db1 was leaked, and newname could overflow. fixed.
This commit is contained in:
cinap_lenrek 2012-12-03 19:16:22 +01:00
parent a16f5cd2a3
commit 2fcd19f16e
1 changed files with 19 additions and 6 deletions
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25
sys/src/ape/lib/ap/plan9/unlink.c
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@ -19,7 +19,7 @@ unlink(const char *path)
long long nn; long long nn;
Dir *db1, *db2, nd; Dir *db1, *db2, nd;
Fdinfo *f; Fdinfo *f;
char *p, newname[PATH_MAX], newelem[32]; char *p, *newname, newelem[32];
/* if the file is already open, make it close-on-exec (and rename to qid) */ /* if the file is already open, make it close-on-exec (and rename to qid) */
if((db1 = _dirstat(path)) == nil) { if((db1 = _dirstat(path)) == nil) {
@ -33,7 +33,10 @@ unlink(const char *path)
db1->qid.vers == db2->qid.vers && db1->qid.vers == db2->qid.vers &&
db1->type == db2->type && db1->type == db2->type &&
db1->dev == db2->dev) { db1->dev == db2->dev) {
sprintf(newelem, "%8.8lx%8.8lx", (ulong)(db2->qid.path>>32), (ulong)db2->qid.path); newname = 0;
sprintf(newelem, "%8.8lx%8.8lx",
(ulong)(db2->qid.path>>32),
(ulong)db2->qid.path);
_nulldir(&nd); _nulldir(&nd);
nd.name = newelem; nd.name = newelem;
if(_dirfwstat(i, &nd) < 0) if(_dirfwstat(i, &nd) < 0)
@ -43,15 +46,23 @@ unlink(const char *path)
if(p == 0) if(p == 0)
p = newelem; p = newelem;
else { else {
memmove(newname, path, p-path); n = p-path;
newname[p-path] = '/'; newname = malloc(n+1+sizeof(newelem));
strcpy(newname+(p-path)+1, newelem); if(newname == 0){
free(db2);
free(db1);
return -1;
}
memmove(newname, path, n);
newname[n] = '/';
strcpy(newname+n+1, newelem);
p = newname; p = newname;
} }
} }
/* reopen remove on close */ /* reopen remove on close */
fd = _OPEN(p, 64|(f->oflags)); fd = _OPEN(p, ORCLOSE|(f->oflags));
if(fd < 0){ if(fd < 0){
free(newname);
free(db2); free(db2);
continue; continue;
} }
@ -61,6 +72,8 @@ unlink(const char *path)
_SEEK(fd, nn, 0); _SEEK(fd, nn, 0);
_DUP(fd, i); _DUP(fd, i);
_CLOSE(fd); _CLOSE(fd);
free(newname);
free(db2);
free(db1); free(db1);
return 0; return 0;
} }