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* [glibc] Use uintptr_t instead of performing pointer subtraction with a null pointer
@ 2023-02-17 20:09 Adhemerval Zanella
0 siblings, 0 replies; only message in thread
From: Adhemerval Zanella @ 2023-02-17 20:09 UTC (permalink / raw)
To: glibc-cvs
https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=cc4d6614b5922c1104125b1f4d0850a88a551882
commit cc4d6614b5922c1104125b1f4d0850a88a551882
Author: Qihao Chencao <twose@qq.com>
Date: Tue Jun 28 16:57:55 2022 +0800
Use uintptr_t instead of performing pointer subtraction with a null pointer
Signed-off-by: Qihao Chencao <twose@qq.com>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Diff:
---
crypt/md5-crypt.c | 12 ++++++------
crypt/sha256-crypt.c | 12 ++++++------
crypt/sha512-crypt.c | 12 ++++++------
elf/dl-minimal-malloc.c | 4 ++--
misc/regexp.c | 5 +++--
nscd/nscd_getgr_r.c | 2 +-
nscd/nscd_gethst_r.c | 5 ++---
nscd/nscd_getserv_r.c | 7 +++----
nss/nss_files/files-alias.c | 2 +-
nss/nss_files/files-parse.c | 2 +-
stdlib/msort.c | 6 +++---
sysdeps/unix/sysv/linux/dl-sysdep.c | 2 +-
12 files changed, 35 insertions(+), 36 deletions(-)
diff --git a/crypt/md5-crypt.c b/crypt/md5-crypt.c
index 791a59767d..0cc597a7f2 100644
--- a/crypt/md5-crypt.c
+++ b/crypt/md5-crypt.c
@@ -110,7 +110,7 @@ __md5_crypt_r (const char *key, const char *salt, char *buffer, int buflen)
salt_len = MIN (strcspn (salt, "$"), 8);
key_len = strlen (key);
- if ((key - (char *) 0) % __alignof__ (md5_uint32) != 0)
+ if (((uintptr_t) key) % __alignof__ (md5_uint32) != 0)
{
char *tmp;
@@ -125,19 +125,19 @@ __md5_crypt_r (const char *key, const char *salt, char *buffer, int buflen)
key = copied_key =
memcpy (tmp + __alignof__ (md5_uint32)
- - (tmp - (char *) 0) % __alignof__ (md5_uint32),
+ - ((uintptr_t) tmp) % __alignof__ (md5_uint32),
key, key_len);
- assert ((key - (char *) 0) % __alignof__ (md5_uint32) == 0);
+ assert (((uintptr_t) key) % __alignof__ (md5_uint32) == 0);
}
- if ((salt - (char *) 0) % __alignof__ (md5_uint32) != 0)
+ if (((uintptr_t) salt) % __alignof__ (md5_uint32) != 0)
{
char *tmp = (char *) alloca (salt_len + __alignof__ (md5_uint32));
salt = copied_salt =
memcpy (tmp + __alignof__ (md5_uint32)
- - (tmp - (char *) 0) % __alignof__ (md5_uint32),
+ - ((uintptr_t) tmp) % __alignof__ (md5_uint32),
salt, salt_len);
- assert ((salt - (char *) 0) % __alignof__ (md5_uint32) == 0);
+ assert (((uintptr_t) salt) % __alignof__ (md5_uint32) == 0);
}
#ifdef USE_NSS
diff --git a/crypt/sha256-crypt.c b/crypt/sha256-crypt.c
index 2a2b356d9a..1ef16af80f 100644
--- a/crypt/sha256-crypt.c
+++ b/crypt/sha256-crypt.c
@@ -142,7 +142,7 @@ __sha256_crypt_r (const char *key, const char *salt, char *buffer, int buflen)
salt_len = MIN (strcspn (salt, "$"), SALT_LEN_MAX);
key_len = strlen (key);
- if ((key - (char *) 0) % __alignof__ (uint32_t) != 0)
+ if (((uintptr_t) key) % __alignof__ (uint32_t) != 0)
{
char *tmp;
@@ -157,20 +157,20 @@ __sha256_crypt_r (const char *key, const char *salt, char *buffer, int buflen)
key = copied_key =
memcpy (tmp + __alignof__ (uint32_t)
- - (tmp - (char *) 0) % __alignof__ (uint32_t),
+ - ((uintptr_t) tmp) % __alignof__ (uint32_t),
key, key_len);
- assert ((key - (char *) 0) % __alignof__ (uint32_t) == 0);
+ assert (((uintptr_t) key) % __alignof__ (uint32_t) == 0);
}
- if ((salt - (char *) 0) % __alignof__ (uint32_t) != 0)
+ if (((uintptr_t) salt) % __alignof__ (uint32_t) != 0)
{
char *tmp = (char *) alloca (salt_len + __alignof__ (uint32_t));
alloca_used += salt_len + __alignof__ (uint32_t);
salt = copied_salt =
memcpy (tmp + __alignof__ (uint32_t)
- - (tmp - (char *) 0) % __alignof__ (uint32_t),
+ - ((uintptr_t) tmp) % __alignof__ (uint32_t),
salt, salt_len);
- assert ((salt - (char *) 0) % __alignof__ (uint32_t) == 0);
+ assert (((uintptr_t) salt) % __alignof__ (uint32_t) == 0);
}
#ifdef USE_NSS
diff --git a/crypt/sha512-crypt.c b/crypt/sha512-crypt.c
index 9deb31ce99..b592eb0976 100644
--- a/crypt/sha512-crypt.c
+++ b/crypt/sha512-crypt.c
@@ -142,7 +142,7 @@ __sha512_crypt_r (const char *key, const char *salt, char *buffer, int buflen)
salt_len = MIN (strcspn (salt, "$"), SALT_LEN_MAX);
key_len = strlen (key);
- if ((key - (char *) 0) % __alignof__ (uint64_t) != 0)
+ if (((uintptr_t) key) % __alignof__ (uint64_t) != 0)
{
char *tmp;
@@ -157,19 +157,19 @@ __sha512_crypt_r (const char *key, const char *salt, char *buffer, int buflen)
key = copied_key =
memcpy (tmp + __alignof__ (uint64_t)
- - (tmp - (char *) 0) % __alignof__ (uint64_t),
+ - ((uintptr_t) tmp) % __alignof__ (uint64_t),
key, key_len);
- assert ((key - (char *) 0) % __alignof__ (uint64_t) == 0);
+ assert (((uintptr_t) key) % __alignof__ (uint64_t) == 0);
}
- if ((salt - (char *) 0) % __alignof__ (uint64_t) != 0)
+ if (((uintptr_t) salt) % __alignof__ (uint64_t) != 0)
{
char *tmp = (char *) alloca (salt_len + __alignof__ (uint64_t));
salt = copied_salt =
memcpy (tmp + __alignof__ (uint64_t)
- - (tmp - (char *) 0) % __alignof__ (uint64_t),
+ - ((uintptr_t) tmp) % __alignof__ (uint64_t),
salt, salt_len);
- assert ((salt - (char *) 0) % __alignof__ (uint64_t) == 0);
+ assert (((uintptr_t) salt) % __alignof__ (uint64_t) == 0);
}
#ifdef USE_NSS
diff --git a/elf/dl-minimal-malloc.c b/elf/dl-minimal-malloc.c
index 2ef8ad34b8..27549645d0 100644
--- a/elf/dl-minimal-malloc.c
+++ b/elf/dl-minimal-malloc.c
@@ -38,13 +38,13 @@ __minimal_malloc (size_t n)
/* Consume any unused space in the last page of our data segment. */
extern int _end attribute_hidden;
alloc_ptr = &_end;
- alloc_end = (void *) 0 + (((alloc_ptr - (void *) 0)
+ alloc_end = (void *) 0 + ((((uintptr_t) alloc_ptr)
+ GLRO(dl_pagesize) - 1)
& ~(GLRO(dl_pagesize) - 1));
}
/* Make sure the allocation pointer is ideally aligned. */
- alloc_ptr = (void *) 0 + (((alloc_ptr - (void *) 0) + MALLOC_ALIGNMENT - 1)
+ alloc_ptr = (void *) 0 + ((((uintptr_t) alloc_ptr) + MALLOC_ALIGNMENT - 1)
& ~(MALLOC_ALIGNMENT - 1));
if (alloc_ptr + n >= alloc_end || n >= -(uintptr_t) alloc_ptr)
diff --git a/misc/regexp.c b/misc/regexp.c
index 5ffdfb35e6..85ff41e909 100644
--- a/misc/regexp.c
+++ b/misc/regexp.c
@@ -23,6 +23,7 @@
argument to 'step' and 'advance' was defined only in regexp.h,
as its definition depended on macros defined by the user. */
+#include <stdint.h>
#include <regex.h>
#include <shlib-compat.h>
@@ -50,7 +51,7 @@ step (const char *string, const char *expbuf)
regmatch_t match; /* We only need info about the full match. */
expbuf += __alignof (regex_t *);
- expbuf -= (expbuf - ((const char *) 0)) % __alignof__ (regex_t *);
+ expbuf -= ((uintptr_t) expbuf) % __alignof__ (regex_t *);
if (__regexec ((const regex_t *) expbuf, string, 1, &match, REG_NOTEOL)
== REG_NOMATCH)
@@ -73,7 +74,7 @@ advance (const char *string, const char *expbuf)
regmatch_t match; /* We only need info about the full match. */
expbuf += __alignof__ (regex_t *);
- expbuf -= (expbuf - ((const char *) 0)) % __alignof__ (regex_t *);
+ expbuf -= ((uintptr_t) expbuf) % __alignof__ (regex_t *);
if (__regexec ((const regex_t *) expbuf, string, 1, &match, REG_NOTEOL)
== REG_NOMATCH
diff --git a/nscd/nscd_getgr_r.c b/nscd/nscd_getgr_r.c
index dab852e8f2..f30d99973d 100644
--- a/nscd/nscd_getgr_r.c
+++ b/nscd/nscd_getgr_r.c
@@ -159,7 +159,7 @@ nscd_getgr_r (const char *key, size_t keylen, request_type type,
/* Now allocate the buffer the array for the group members. We must
align the pointer. */
- align = ((__alignof__ (char *) - (p - ((char *) 0)))
+ align = ((__alignof__ (char *) - ((uintptr_t) p))
& (__alignof__ (char *) - 1));
total_len = (align + (1 + gr_resp.gr_mem_cnt) * sizeof (char *)
+ gr_resp.gr_name_len + gr_resp.gr_passwd_len);
diff --git a/nscd/nscd_gethst_r.c b/nscd/nscd_gethst_r.c
index 153194ad04..ab9c9d311f 100644
--- a/nscd/nscd_gethst_r.c
+++ b/nscd/nscd_gethst_r.c
@@ -244,10 +244,9 @@ nscd_gethst_r (const char *key, size_t keylen, request_type type,
/* A first check whether the buffer is sufficiently large is possible. */
/* Now allocate the buffer the array for the group members. We must
align the pointer and the base of the h_addr_list pointers. */
- align1 = ((__alignof__ (char *) - (cp - ((char *) 0)))
+ align1 = ((__alignof__ (char *) - ((uintptr_t) cp))
& (__alignof__ (char *) - 1));
- align2 = ((__alignof__ (char *) - ((cp + align1 + hst_resp.h_name_len)
- - ((char *) 0)))
+ align2 = ((__alignof__ (char *) - ((uintptr_t) (cp + align1 + hst_resp.h_name_len)))
& (__alignof__ (char *) - 1));
if (buflen < (align1 + hst_resp.h_name_len + align2
+ ((hst_resp.h_aliases_cnt + hst_resp.h_addr_list_cnt
diff --git a/nscd/nscd_getserv_r.c b/nscd/nscd_getserv_r.c
index 0ee83ff88c..6969fcb739 100644
--- a/nscd/nscd_getserv_r.c
+++ b/nscd/nscd_getserv_r.c
@@ -205,11 +205,10 @@ nscd_getserv_r (const char *crit, size_t critlen, const char *proto,
/* A first check whether the buffer is sufficiently large is possible. */
/* Now allocate the buffer the array for the group members. We must
align the pointer and the base of the h_addr_list pointers. */
- align1 = ((__alignof__ (char *) - (cp - ((char *) 0)))
+ align1 = ((__alignof__ (char *) - ((uintptr_t) cp))
& (__alignof__ (char *) - 1));
- align2 = ((__alignof__ (char *) - ((cp + align1 + serv_resp.s_name_len
- + serv_resp.s_proto_len)
- - ((char *) 0)))
+ align2 = ((__alignof__ (char *) - ((uintptr_t) (cp + align1 + serv_resp.s_name_len
+ + serv_resp.s_proto_len)))
& (__alignof__ (char *) - 1));
if (buflen < (align1 + serv_resp.s_name_len + serv_resp.s_proto_len
+ align2
diff --git a/nss/nss_files/files-alias.c b/nss/nss_files/files-alias.c
index 1c32884fe7..4601cb6ce9 100644
--- a/nss/nss_files/files-alias.c
+++ b/nss/nss_files/files-alias.c
@@ -281,7 +281,7 @@ get_next_alias (FILE *stream, const char *match, struct aliasent *result,
/* Adjust the pointer so it is aligned for
storing pointers. */
first_unused += __alignof__ (char *) - 1;
- first_unused -= ((first_unused - (char *) 0)
+ first_unused -= (((uintptr_t) first_unused)
% __alignof__ (char *));
result->alias_members = (char **) first_unused;
diff --git a/nss/nss_files/files-parse.c b/nss/nss_files/files-parse.c
index 632ba0a880..77333b18fe 100644
--- a/nss/nss_files/files-parse.c
+++ b/nss/nss_files/files-parse.c
@@ -239,7 +239,7 @@ parse_list (char **linep, char *eol, char *buf_end, int terminator_c,
/* Adjust the pointer so it is aligned for storing pointers. */
eol += __alignof__ (char *) - 1;
- eol -= (eol - (char *) 0) % __alignof__ (char *);
+ eol -= ((uintptr_t) eol) % __alignof__ (char *);
/* We will start the storage here for the vector of pointers. */
list = (char **) eol;
diff --git a/stdlib/msort.c b/stdlib/msort.c
index 6dd1cc3aa1..bbaa5e9f82 100644
--- a/stdlib/msort.c
+++ b/stdlib/msort.c
@@ -281,15 +281,15 @@ __qsort_r (void *b, size_t n, size_t s, __compar_d_fn_t cmp, void *arg)
else
{
if ((s & (sizeof (uint32_t) - 1)) == 0
- && ((char *) b - (char *) 0) % __alignof__ (uint32_t) == 0)
+ && ((uintptr_t) b) % __alignof__ (uint32_t) == 0)
{
if (s == sizeof (uint32_t))
p.var = 0;
else if (s == sizeof (uint64_t)
- && ((char *) b - (char *) 0) % __alignof__ (uint64_t) == 0)
+ && ((uintptr_t) b) % __alignof__ (uint64_t) == 0)
p.var = 1;
else if ((s & (sizeof (unsigned long) - 1)) == 0
- && ((char *) b - (char *) 0)
+ && ((uintptr_t) b)
% __alignof__ (unsigned long) == 0)
p.var = 2;
}
diff --git a/sysdeps/unix/sysv/linux/dl-sysdep.c b/sysdeps/unix/sysv/linux/dl-sysdep.c
index 7065df8ace..1b3dd869b5 100644
--- a/sysdeps/unix/sysv/linux/dl-sysdep.c
+++ b/sysdeps/unix/sysv/linux/dl-sysdep.c
@@ -129,7 +129,7 @@ _dl_sysdep_start (void **start_argptr,
break up that far. When the user program examines its break, it
will see this new value and not clobber our data. */
__sbrk (GLRO(dl_pagesize)
- - ((_end - (char *) 0) & (GLRO(dl_pagesize) - 1)));
+ - (((uintptr_t) _end) & (GLRO(dl_pagesize) - 1)));
/* If this is a SUID program we make sure that FDs 0, 1, and 2 are
allocated. If necessary we are doing it ourself. If it is not
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