diff options
-rw-r--r-- | libc/inet/rpc/rcmd.c | 60 | ||||
-rw-r--r-- | libc/sysdeps/linux/common/bits/uClibc_alloc.h | 26 | ||||
-rw-r--r-- | libc/sysdeps/linux/common/getdents.c | 10 | ||||
-rw-r--r-- | libc/sysdeps/linux/common/getdents64.c | 10 |
4 files changed, 54 insertions, 52 deletions
diff --git a/libc/inet/rpc/rcmd.c b/libc/inet/rpc/rcmd.c index 628c291fe..fb1bd9320 100644 --- a/libc/inet/rpc/rcmd.c +++ b/libc/inet/rpc/rcmd.c @@ -69,7 +69,6 @@ static char sccsid[] = "@(#)rcmd.c 8.3 (Berkeley) 3/26/94"; #include <netinet/in.h> #include <arpa/inet.h> -#include <alloca.h> #include <signal.h> #include <fcntl.h> #include <netdb.h> @@ -86,6 +85,7 @@ static char sccsid[] = "@(#)rcmd.c 8.3 (Berkeley) 3/26/94"; #include <wchar.h> #endif #include <sys/uio.h> +#include <bits/uClibc_alloc.h> /* some forward declarations */ @@ -116,11 +116,7 @@ int rcmd(char **ahost, u_short rport, const char *locuser, const char *remuser, #ifdef __UCLIBC_HAS_REENTRANT_RPC__ hstbuflen = 1024; -#ifdef __ARCH_USE_MMU__ - tmphstbuf = alloca (hstbuflen); -#else - tmphstbuf = malloc (hstbuflen); -#endif + tmphstbuf = stack_heap_alloc(hstbuflen); while (gethostbyname_r (*ahost, &hostbuf, tmphstbuf, hstbuflen, &hp, &herr) != 0 || hp == NULL) @@ -128,9 +124,7 @@ int rcmd(char **ahost, u_short rport, const char *locuser, const char *remuser, if (herr != NETDB_INTERNAL || errno != ERANGE) { __set_h_errno (herr); -#ifndef __ARCH_USE_MMU__ - free(tmphstbuf); -#endif + stack_heap_free(tmphstbuf); herror(*ahost); return -1; } @@ -138,17 +132,11 @@ int rcmd(char **ahost, u_short rport, const char *locuser, const char *remuser, { /* Enlarge the buffer. */ hstbuflen *= 2; -#ifdef __ARCH_USE_MMU__ - tmphstbuf = alloca (hstbuflen); -#else - free(tmphstbuf); - tmphstbuf = malloc (hstbuflen); -#endif + stack_heap_free(tmphstbuf); + tmphstbuf = stack_heap_alloc(hstbuflen); } } -#ifndef __ARCH_USE_MMU__ - free(tmphstbuf); -#endif + stack_heap_free(tmphstbuf); #else /* call the non-reentrant version */ if ((hp = gethostbyname(*ahost)) == NULL) { return -1; @@ -331,35 +319,23 @@ int ruserok(const char *rhost, int superuser, const char *ruser, #ifdef __UCLIBC_HAS_REENTRANT_RPC__ buflen = 1024; -#ifdef __ARCH_USE_MMU__ - buffer = alloca (buflen); -#else - buffer = malloc (buflen); -#endif + buffer = stack_heap_alloc(buflen); while (gethostbyname_r (rhost, &hostbuf, buffer, buflen, &hp, &herr) != 0 || hp == NULL) { if (herr != NETDB_INTERNAL || errno != ERANGE) { -#ifndef __ARCH_USE_MMU__ - free(buffer); -#endif + stack_heap_free(buffer); return -1; } else { /* Enlarge the buffer. */ buflen *= 2; -#ifdef __ARCH_USE_MMU__ - buffer = alloca (buflen); -#else - free(buffer); - buffer = malloc (buflen); -#endif + stack_heap_free(buffer); + buffer = stack_heap_alloc(buflen); } } -#ifndef __ARCH_USE_MMU__ - free(buffer); -#endif + stack_heap_free(buffer); #else if ((hp = gethostbyname(rhost)) == NULL) { return -1; @@ -452,23 +428,15 @@ iruserok2 (u_int32_t raddr, int superuser, const char *ruser, const char *luser, #ifdef __UCLIBC_HAS_REENTRANT_RPC__ size_t buflen = sysconf (_SC_GETPW_R_SIZE_MAX); struct passwd pwdbuf; -#ifdef __ARCH_USE_MMU__ - char *buffer = alloca (buflen); -#else - char *buffer = malloc (buflen); -#endif + char *buffer = stack_heap_alloc(buflen); if (getpwnam_r (luser, &pwdbuf, buffer, buflen, &pwd) != 0 || pwd == NULL) { -#ifndef __ARCH_USE_MMU__ - free(buffer); -#endif + stack_heap_free(buffer); return -1; } -#ifndef __ARCH_USE_MMU__ - free(buffer); -#endif + stack_heap_free(buffer); #else if ((pwd = getpwnam(luser)) == NULL) return -1; diff --git a/libc/sysdeps/linux/common/bits/uClibc_alloc.h b/libc/sysdeps/linux/common/bits/uClibc_alloc.h new file mode 100644 index 000000000..6a70d27b7 --- /dev/null +++ b/libc/sysdeps/linux/common/bits/uClibc_alloc.h @@ -0,0 +1,26 @@ +/* + * Macros to transparently switch between the stack and heap for large + * allocations. The former is useful on MMU systems as it results in + * smaller code, but the latter is required on NoMMU systems. This is + * due to small stacks that cannot grow and so doing large allocs will + * cause a stack overflow. + * + * Copyright (C) 2010 Mike Frysinger <vapier@gentoo.org> + * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball. + */ + +#ifndef _UCLIBC_ALLOC_H +#define _UCLIBC_ALLOC_H + +#include <alloca.h> +#include <stdlib.h> + +#ifdef __ARCH_USE_MMU__ +# define stack_heap_alloc(x) alloca(x) +# define stack_heap_free(x) do { if (0) free(x); } while (0) +#else +# define stack_heap_alloc(x) malloc(x) +# define stack_heap_free(x) free(x) +#endif + +#endif diff --git a/libc/sysdeps/linux/common/getdents.c b/libc/sysdeps/linux/common/getdents.c index 5dda190a8..46f7b8e16 100644 --- a/libc/sysdeps/linux/common/getdents.c +++ b/libc/sysdeps/linux/common/getdents.c @@ -4,7 +4,6 @@ * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball. */ -#include <alloca.h> #include <assert.h> #include <errno.h> #include <dirent.h> @@ -17,6 +16,7 @@ #include <sys/syscall.h> #include <bits/kernel_types.h> #include <bits/kernel-features.h> +#include <bits/uClibc_alloc.h> #if !(defined __UCLIBC_HAS_LFS__ && defined __NR_getdents64 && __WORDSIZE == 64) /* If the condition above is met, __getdents is defined as an alias @@ -93,11 +93,13 @@ ssize_t __getdents (int fd, char *buf, size_t nbytes) nbytes - size_diff); dp = (struct dirent *) buf; - skdp = kdp = alloca (red_nbytes); + skdp = kdp = stack_heap_alloc(red_nbytes); retval = __syscall_getdents(fd, (unsigned char *)kdp, red_nbytes); - if (retval == -1) + if (retval == -1) { + stack_heap_free(skdp); return -1; + } while ((char *) kdp < (char *) skdp + retval) { const size_t alignment = __alignof__ (struct dirent); @@ -114,6 +116,7 @@ ssize_t __getdents (int fd, char *buf, size_t nbytes) if ((char *) dp == buf) { /* The buffer the user passed in is too small to hold even one entry. */ + stack_heap_free(skdp); __set_errno (EINVAL); return -1; } @@ -130,6 +133,7 @@ ssize_t __getdents (int fd, char *buf, size_t nbytes) dp = (struct dirent *) ((char *) dp + new_reclen); kdp = (struct kernel_dirent *) (((char *) kdp) + kdp->d_reclen); } + stack_heap_free(skdp); return (char *) dp - buf; } diff --git a/libc/sysdeps/linux/common/getdents64.c b/libc/sysdeps/linux/common/getdents64.c index 37cb4c6f8..30686f25a 100644 --- a/libc/sysdeps/linux/common/getdents64.c +++ b/libc/sysdeps/linux/common/getdents64.c @@ -5,7 +5,6 @@ */ #include <features.h> -#include <alloca.h> #include <assert.h> #include <errno.h> #include <dirent.h> @@ -17,6 +16,7 @@ #include <sys/types.h> #include <sys/syscall.h> #include <bits/kernel_types.h> +#include <bits/uClibc_alloc.h> #if defined __UCLIBC_HAS_LFS__ && defined __NR_getdents64 @@ -52,11 +52,13 @@ ssize_t __getdents64 (int fd, char *buf, size_t nbytes) nbytes - size_diff); dp = (struct dirent64 *) buf; - skdp = kdp = alloca (red_nbytes); + skdp = kdp = stack_heap_alloc(red_nbytes); retval = __syscall_getdents64(fd, (unsigned char *)kdp, red_nbytes); - if (retval == -1) + if (retval == -1) { + stack_heap_free(skdp); return -1; + } while ((char *) kdp < (char *) skdp + retval) { const size_t alignment = __alignof__ (struct dirent64); @@ -73,6 +75,7 @@ ssize_t __getdents64 (int fd, char *buf, size_t nbytes) if ((char *) dp == buf) { /* The buffer the user passed in is too small to hold even one entry. */ + stack_heap_free(skdp); __set_errno (EINVAL); return -1; } @@ -89,6 +92,7 @@ ssize_t __getdents64 (int fd, char *buf, size_t nbytes) dp = (struct dirent64 *) ((char *) dp + new_reclen); kdp = (struct kernel_dirent64 *) (((char *) kdp) + kdp->d_reclen); } + stack_heap_free(skdp); return (char *) dp - buf; } |