For the prlimit64 syscall the kernel expects an rlimit struct with 64-bit
fields,
but on 32-bit CPUs without _FILE_OFFSET_BITS=64 the struct rlimit has 32-bit
fields.
Add safe implementations of getrlimit, setrlimit, prlimit for 32-bit CPUs with a
local struct rlimit64 variable for use in the prlimit64 syscall.
For 64-bit CPUs and configurations with _FILE_OFFSET_BITS=64 use
getrlimit, setrlimit, prlimit as aliases to getrlimit64, setrlimit64 and
prlimit64. Add a new function prlimit64.
Tested on aarch64, arm, i386, arc.
Fixes: 95e38b37 ("add support for systems without legacy setrlimit/getrlimit
syscalls")
Signed-off-by: Pavel Kozlov <pavel.koz...@synopsys.com>
---
include/sys/resource.h | 4 ++
libc/sysdeps/linux/common/getrlimit.c | 55 ++++++++++++++++++-------
libc/sysdeps/linux/common/getrlimit64.c | 26 ++++++++++--
libc/sysdeps/linux/common/prlimit.c | 53 +++++++++++++++++++++---
libc/sysdeps/linux/common/prlimit64.c | 36 ++++++++++++++++
libc/sysdeps/linux/common/setrlimit.c | 41 +++++++++++-------
libc/sysdeps/linux/common/setrlimit64.c | 24 +++++++++--
7 files changed, 197 insertions(+), 42 deletions(-)
create mode 100644 libc/sysdeps/linux/common/prlimit64.c
diff --git a/include/sys/resource.h b/include/sys/resource.h
index 00c63ff0f1e5..e9fac2c656bf 100644
--- a/include/sys/resource.h
+++ b/include/sys/resource.h
@@ -106,6 +106,10 @@ libc_hidden_proto(setpriority)
extern int prlimit (__pid_t __pid, enum __rlimit_resource __resource,
const struct rlimit *__new_limit,
struct rlimit *__old_limit) __THROW;
+
+extern int prlimit64 (__pid_t __pid, enum __rlimit_resource __resource,
+ const struct rlimit64 *__new_limit,
+ struct rlimit64 *__old_limit) __THROW;
#endif
__END_DECLS
diff --git a/libc/sysdeps/linux/common/getrlimit.c
b/libc/sysdeps/linux/common/getrlimit.c
index ad3f4a0e494d..46726fcbd94f 100644
--- a/libc/sysdeps/linux/common/getrlimit.c
+++ b/libc/sysdeps/linux/common/getrlimit.c
@@ -24,21 +24,53 @@ int getrlimit(__rlimit_resource_t resource, struct rlimit
*rlimits)
{
return __syscall_ugetrlimit(resource, rlimits);
}
+libc_hidden_def(getrlimit)
-#else
-
-# if !defined(__UCLIBC_HANDLE_OLDER_RLIMIT__)
+#elif defined(__NR_prlimit64)
+/* Use prlimit64 if present, the prlimit64 syscall is free from a back
+ compatibility stuff for an old getrlimit */
-# if defined(__NR_prlimit64)
+# if __WORDSIZE == 32 && !defined(__USE_FILE_OFFSET64)
+/* If struct rlimit has 64-bit fields (if __WORDSIZE == 64 or
__USE_FILE_OFFSET64
+ is defined), then use getrlimit as an alias to getrlimit64, see
getrlimit64.c */
int getrlimit(__rlimit_resource_t resource, struct rlimit *rlimits)
{
- return INLINE_SYSCALL (prlimit64, 4, 0, resource, NULL, rlimits);
+ struct rlimit64 rlimits64;
+ int res = INLINE_SYSCALL (prlimit64, 4, 0, resource, NULL, &rlimits64);
+
+ if (res == 0) {
+ /* If the syscall succeeds but the values do not fit into a
+ rlimit structure set EOVERFLOW errno and retrun -1. */
+ rlimits->rlim_cur = rlimits64.rlim_cur;
+ if (rlimits64.rlim_cur != rlimits->rlim_cur) {
+ if (rlimits64.rlim_cur != RLIM64_INFINITY) {
+ __set_errno(EOVERFLOW);
+ return -1;
+ }
+ rlimits->rlim_cur = RLIM_INFINITY;
+ }
+
+ rlimits->rlim_max = rlimits64.rlim_max;
+ if (rlimits64.rlim_max != rlimits->rlim_max) {
+ if (rlimits64.rlim_max != RLIM64_INFINITY) {
+ __set_errno(EOVERFLOW);
+ return -1;
+ }
+ rlimits->rlim_max = RLIM_INFINITY;
+ }
+ }
+ return res;
}
-# else
+libc_hidden_def(getrlimit)
+# endif
+
+#else
+
+# if !defined(__UCLIBC_HANDLE_OLDER_RLIMIT__)
+
/* We don't need to wrap getrlimit() */
_syscall2(int, getrlimit, __rlimit_resource_t, resource,
struct rlimit *, rlim)
-# endif
# else
@@ -51,11 +83,7 @@ int getrlimit(__rlimit_resource_t resource, struct rlimit *rlimits)
{
int result;
-# if defined(__NR_prlimit64)
- result = INLINE_SYSCALL (prlimit64, 4, 0, resource, NULL, rlimits);
-# else
result = __syscall_getrlimit(resource, rlimits);
-# endif
if (result == -1)
return result;
@@ -69,9 +97,6 @@ int getrlimit(__rlimit_resource_t resource, struct rlimit
*rlimits)
return result;
}
# endif
-#endif
-libc_hidden_def(getrlimit)
-#if __WORDSIZE == 64
-strong_alias_untyped(getrlimit, getrlimit64)
+libc_hidden_def(getrlimit)
#endif
diff --git a/libc/sysdeps/linux/common/getrlimit64.c
b/libc/sysdeps/linux/common/getrlimit64.c
index be98098a1ee0..47f1410fb3d9 100644
--- a/libc/sysdeps/linux/common/getrlimit64.c
+++ b/libc/sysdeps/linux/common/getrlimit64.c
@@ -17,14 +17,31 @@
#include <_lfs_64.h>
#include <bits/wordsize.h>
+#include <sys/resource.h>
+#include <sys/syscall.h>
+#include <stddef.h> // needed for NULL to be defined
-/* the regular getrlimit will work just fine for 64bit users */
-#if __WORDSIZE == 32
-# include <sys/resource.h>
+#if defined(__NR_prlimit64)
+
+/* the regular prlimit64 will work just fine for 64-bit users */
+int getrlimit64 (__rlimit_resource_t resource, struct rlimit64 *rlimits)
+{
+ return INLINE_SYSCALL (prlimit64, 4, 0, resource, NULL, rlimits);
+}
+
+# if !defined(__NR_ugetrlimit) && (__WORDSIZE == 64 || defined
(__USE_FILE_OFFSET64))
+/* If getrlimit is not implemented through the __NR_ugetrlimit and size of
+ rlimit_t == rlimit64_t then use getrlimit as an alias to getrlimit64 */
+strong_alias_untyped(getrlimit64, getrlimit)
+libc_hidden_def(getrlimit)
+# endif
+
+#else
/* Put the soft and hard limits for RESOURCE in *RLIMITS.
- Returns 0 if successful, -1 if not (and sets errno). */
+ Returns 0 if successful, -1 if not (and sets errno).
+ The regular getrlimit will work just fine for 64-bit users */
int getrlimit64 (__rlimit_resource_t resource, struct rlimit64 *rlimits)
{
struct rlimit rlimits32;
@@ -44,3 +61,4 @@ int getrlimit64 (__rlimit_resource_t resource, struct
rlimit64 *rlimits)
return 0;
}
#endif
+
diff --git a/libc/sysdeps/linux/common/prlimit.c
b/libc/sysdeps/linux/common/prlimit.c
index f44dc166492e..f59ade3a379c 100644
--- a/libc/sysdeps/linux/common/prlimit.c
+++ b/libc/sysdeps/linux/common/prlimit.c
@@ -17,14 +17,57 @@
#include <sys/resource.h>
#include <sysdep.h>
-#include <bits/kernel-features.h>
+#include <stddef.h> // needed for NULL to be defined
-#if defined __ASSUME_PRLIMIT64
+#if defined(__NR_prlimit64) && __WORDSIZE == 32 &&
!defined(__USE_FILE_OFFSET64)
int
prlimit (__pid_t pid, enum __rlimit_resource resource,
- const struct rlimit *new_rlimit, struct rlimit *old_rlimit)
+ const struct rlimit *new_rlimit, struct rlimit *old_rlimit)
{
- return INLINE_SYSCALL (prlimit64, 4, pid, resource, new_rlimit,
- old_rlimit);
+ struct rlimit64 new_rlimit64;
+ struct rlimit64 old_rlimit64;
+ int res;
+
+ if (new_rlimit != NULL) {
+ if (new_rlimit->rlim_cur == RLIM_INFINITY)
+ new_rlimit64.rlim_cur = RLIM64_INFINITY;
+ else
+ new_rlimit64.rlim_cur = new_rlimit->rlim_cur;
+ if (new_rlimit->rlim_max == RLIM_INFINITY)
+ new_rlimit64.rlim_max = RLIM64_INFINITY;
+ else
+ new_rlimit64.rlim_max = new_rlimit->rlim_max;
+ }
+
+ res = INLINE_SYSCALL (prlimit64, 4, pid, resource, &new_rlimit64,
+ &old_rlimit64);
+
+ if (res == 0 && old_rlimit != NULL) {
+ /* If the syscall succeeds but the values do not fit into a
+ rlimit structure set EOVERFLOW errno and retrun -1.
+ With current Linux implementation of the prlimit64 syscall,
+ overflow can't happen. An extra condition has been added to
get
+ the same behavior as in glibc for future potential
overflows. */
+ old_rlimit->rlim_cur = old_rlimit64.rlim_cur;
+ if (old_rlimit64.rlim_cur != old_rlimit->rlim_cur) {
+ if (new_rlimit == NULL &&
+ old_rlimit64.rlim_cur != RLIM64_INFINITY) {
+ __set_errno(EOVERFLOW);
+ return -1;
+ }
+ old_rlimit->rlim_cur = RLIM_INFINITY;
+ }
+ old_rlimit->rlim_max = old_rlimit64.rlim_max;
+ if (old_rlimit64.rlim_max != old_rlimit->rlim_max) {
+ if (new_rlimit == NULL &&
+ old_rlimit64.rlim_max != RLIM64_INFINITY) {
+ __set_errno(EOVERFLOW);
+ return -1;
+ }
+ old_rlimit->rlim_cur = RLIM_INFINITY;
+ }
+ }
+
+ return res;
}
#endif
diff --git a/libc/sysdeps/linux/common/prlimit64.c
b/libc/sysdeps/linux/common/prlimit64.c
new file mode 100644
index 000000000000..6f57b939eeca
--- /dev/null
+++ b/libc/sysdeps/linux/common/prlimit64.c
@@ -0,0 +1,36 @@
+/* Copyright (C) 2023 uClibc-ng
+ * An prlimit64() - get/set resource limits Linux specific syscall.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, see
+ * <http://www.gnu.org/licenses/>.
+ */
+
+#include <sys/resource.h>
+#include <sysdep.h>
+
+#if defined(__NR_prlimit64)
+
+int
+prlimit64 (__pid_t pid, enum __rlimit_resource resource,
+ const struct rlimit64 *new_rlimit, struct rlimit64 *old_rlimit)
+{
+ return INLINE_SYSCALL (prlimit64, 4, pid, resource, new_rlimit,
+ old_rlimit);
+}
+
+# if __WORDSIZE == 64 || defined (__USE_FILE_OFFSET64)
+strong_alias_untyped(prlimit64, prlimit)
+# endif
+
+#endif
\ No newline at end of file
diff --git a/libc/sysdeps/linux/common/setrlimit.c
b/libc/sysdeps/linux/common/setrlimit.c
index 8381afc617fd..9c6707235f3e 100644
--- a/libc/sysdeps/linux/common/setrlimit.c
+++ b/libc/sysdeps/linux/common/setrlimit.c
@@ -23,21 +23,41 @@ int setrlimit(__rlimit_resource_t resource, const struct
rlimit *rlimits)
{
return __syscall_usetrlimit(resource, rlimits);
}
+libc_hidden_def(setrlimit)
-#else
+#elif defined(__NR_prlimit64)
-# if !defined(__UCLIBC_HANDLE_OLDER_RLIMIT__)
+/* Use prlimit64 if present, the prlimit64 syscall is free from a back
+ compatibility stuff for setrlimit */
-# if defined(__NR_prlimit64)
+ # if __WORDSIZE == 32 && !defined(__USE_FILE_OFFSET64)
+/* If struct rlimit has 64-bit fields (if __WORDSIZE == 64 or
__USE_FILE_OFFSET64
+ is defined), then use setrlimit as an alias to setrlimit64, see
setrlimit64.c */
int setrlimit(__rlimit_resource_t resource, const struct rlimit *rlimits)
{
- return INLINE_SYSCALL (prlimit64, 4, 0, resource, rlimits, NULL);
+ struct rlimit64 rlimits64;
+
+ if (rlimits->rlim_cur == RLIM_INFINITY)
+ rlimits64.rlim_cur = RLIM64_INFINITY;
+ else
+ rlimits64.rlim_cur = rlimits->rlim_cur;
+ if (rlimits->rlim_max == RLIM_INFINITY)
+ rlimits64.rlim_max = RLIM64_INFINITY;
+ else
+ rlimits64.rlim_max = rlimits->rlim_max;
+
+ return INLINE_SYSCALL (prlimit64, 4, 0, resource, &rlimits64, NULL);
}
-# else
+libc_hidden_def(setrlimit)
+# endif
+
+#else
+
+# if !defined(__UCLIBC_HANDLE_OLDER_RLIMIT__)
+
/* We don't need to wrap setrlimit() */
_syscall2(int, setrlimit, __rlimit_resource_t, resource,
const struct rlimit *, rlim)
-# endif
# else
@@ -66,16 +86,9 @@ int setrlimit(__rlimit_resource_t resource, const struct rlimit *rlimits)
RLIM_INFINITY
>> 1);
rlimits_small.rlim_max = MIN((unsigned long int) rlimits->rlim_max,
RLIM_INFINITY
>> 1);
-# if defined(__NR_prlimit64)
- return INLINE_SYSCALL (prlimit64, 4, 0, resource, &rlimits_small, NULL);
-# else
return __syscall_setrlimit(resource, &rlimits_small);
-# endif
}
# endif
-#endif
-libc_hidden_def(setrlimit)
-#if __WORDSIZE == 64
-strong_alias_untyped(setrlimit, setrlimit64)
+libc_hidden_def(setrlimit)
#endif
diff --git a/libc/sysdeps/linux/common/setrlimit64.c
b/libc/sysdeps/linux/common/setrlimit64.c
index fee14f4ad4b2..3446c58fee12 100644
--- a/libc/sysdeps/linux/common/setrlimit64.c
+++ b/libc/sysdeps/linux/common/setrlimit64.c
@@ -17,15 +17,31 @@
#include <_lfs_64.h>
#include <bits/wordsize.h>
+#include <sys/resource.h>
+#include <sys/syscall.h>
+#include <stddef.h> // needed for NULL to be defined
-/* the regular setrlimit will work just fine for 64bit users */
-#if __WORDSIZE == 32
-# include <sys/resource.h>
+#if defined(__NR_prlimit64)
+
+int setrlimit64 (__rlimit_resource_t resource, const struct rlimit64 *rlimits)
+{
+ return INLINE_SYSCALL (prlimit64, 4, 0, resource, rlimits, NULL);
+}
+
+# if !defined(__NR_usetrlimit) && (__WORDSIZE == 64 || defined
(__USE_FILE_OFFSET64))
+/* If setrlimit is not implemented through the __NR_usetrlimit and size of
+ rlimit_t == rlimit64_t then use setrlimit as an alias to setrlimit64 */
+strong_alias_untyped(setrlimit64, setrlimit)
+libc_hidden_def(setrlimit)
+# endif
+
+#else
/* Set the soft and hard limits for RESOURCE to *RLIMITS.
Only the super-user can increase hard limits.
- Return 0 if successful, -1 if not (and sets errno). */
+ Return 0 if successful, -1 if not (and sets errno).
+ The regular setrlimit will work just fine for 64bit users */
int setrlimit64 (__rlimit_resource_t resource, const struct rlimit64 *rlimits)
{
struct rlimit rlimits32;
