From: "H.J. Lu" <hjl.tools@gmail.com>
To: libc-stable@sourceware.org
Subject: [2.31/2.30] [PATCH 2/6] Add SYSCALL_ULONG_ARG_[12] to pass long to syscall [BZ #25810]
Date: Thu, 30 Apr 2020 12:34:19 -0700 [thread overview]
Message-ID: <20200430193423.807713-3-hjl.tools@gmail.com> (raw)
In-Reply-To: <20200430193423.807713-1-hjl.tools@gmail.com>
X32 has 32-bit long and pointer with 64-bit off_t. Since x32 psABI
requires that pointers passed in registers must be zero-extended to
64bit, x32 can share many syscall interfaces with LP64. When a LP64
syscall with long and unsigned long int arguments is used for x32, these
arguments must be properly extended to 64-bit. Otherwise if the upper
32 bits of the register have undefined value, such a syscall will be
rejected by kernel.
For syscalls implemented in assembly codes, 'U' is added to syscall
signature key letters for unsigned long, which is zero-extended to
64-bit types. SYSCALL_ULONG_ARG_1 and SYSCALL_ULONG_ARG_2 are passed
to syscall-template.S for the first and the second unsigned long int
arguments if PSEUDOS_HAVE_ULONG_INDICES is defined. They are used by
x32 to zero-extend 32-bit arguments to 64 bits.
Tested on i386, x86-64 and x32 as well as with build-many-glibcs.py.
(cherry picked from commit 2ad5d0845d80589d0adf86593bd36a7c71a521f8)
---
sysdeps/unix/make-syscalls.sh | 24 +++++++
sysdeps/unix/syscall-template.S | 49 +++++++++++++-
sysdeps/unix/syscalls.list | 8 +--
sysdeps/unix/sysv/linux/syscalls.list | 16 ++---
sysdeps/unix/sysv/linux/x86_64/sysdep.h | 71 +++++++++++++++++----
sysdeps/unix/sysv/linux/x86_64/x32/sysdep.h | 21 +++++-
6 files changed, 159 insertions(+), 30 deletions(-)
diff --git a/sysdeps/unix/make-syscalls.sh b/sysdeps/unix/make-syscalls.sh
index c07626677f..4f6c3490a2 100644
--- a/sysdeps/unix/make-syscalls.sh
+++ b/sysdeps/unix/make-syscalls.sh
@@ -30,6 +30,7 @@
# P: optionally-NULL pointer to typed object (e.g., 3rd argument to sigaction)
# s: non-NULL string (e.g., 1st arg to open)
# S: optionally-NULL string (e.g., 1st arg to acct)
+# U: unsigned long int (32-bit types are zero-extended to 64-bit types)
# v: vararg scalar (e.g., optional 3rd arg to open)
# V: byte-per-page vector (3rd arg to mincore)
# W: wait status, optionally-NULL pointer to int (e.g., 2nd arg of wait4)
@@ -184,6 +185,27 @@ while read file srcfile caller syscall args strong weak; do
?:?????????) nargs=9;;
esac
+ # Derive the unsigned long int arguments from the argument signature
+ ulong_arg_1=0
+ ulong_arg_2=0
+ ulong_count=0
+ for U in $(echo $args | sed -e "s/.*:/:/" | grep -ob U)
+ do
+ ulong_count=$(expr $ulong_count + 1)
+ ulong_arg=$(echo $U | sed -e "s/:U//")
+ case $ulong_count in
+ 1)
+ ulong_arg_1=$ulong_arg
+ ;;
+ 2)
+ ulong_arg_2=$ulong_arg
+ ;;
+ *)
+ echo >&2 "$0: Too many unsigned long int arguments for syscall ($strong $weak)"
+ exit 2
+ esac
+ done
+
# Make sure only the first syscall rule is used, if multiple dirs
# define the same syscall.
echo ''
@@ -245,6 +267,8 @@ while read file srcfile caller syscall args strong weak; do
\$(make-target-directory)
(echo '#define SYSCALL_NAME $syscall'; \\
echo '#define SYSCALL_NARGS $nargs'; \\
+ echo '#define SYSCALL_ULONG_ARG_1 $ulong_arg_1'; \\
+ echo '#define SYSCALL_ULONG_ARG_2 $ulong_arg_2'; \\
echo '#define SYSCALL_SYMBOL $strong'; \\
echo '#define SYSCALL_NOERRNO $noerrno'; \\
echo '#define SYSCALL_ERRVAL $errval'; \\
diff --git a/sysdeps/unix/syscall-template.S b/sysdeps/unix/syscall-template.S
index cf6c7a58fb..f807a8603f 100644
--- a/sysdeps/unix/syscall-template.S
+++ b/sysdeps/unix/syscall-template.S
@@ -25,6 +25,12 @@
defining a few macros:
SYSCALL_NAME syscall name
SYSCALL_NARGS number of arguments this call takes
+ SYSCALL_ULONG_ARG_1 the first unsigned long int argument this
+ call takes. 0 means that there are no
+ unsigned long int arguments.
+ SYSCALL_ULONG_ARG_2 the second unsigned long int argument this
+ call takes. 0 means that there is at most
+ one unsigned long int argument.
SYSCALL_SYMBOL primary symbol name
SYSCALL_NOERRNO 1 to define a no-errno version (see below)
SYSCALL_ERRVAL 1 to define an error-value version (see below)
@@ -44,9 +50,31 @@
/* This indirection is needed so that SYMBOL gets macro-expanded. */
#define syscall_hidden_def(SYMBOL) hidden_def (SYMBOL)
-#define T_PSEUDO(SYMBOL, NAME, N) PSEUDO (SYMBOL, NAME, N)
-#define T_PSEUDO_NOERRNO(SYMBOL, NAME, N) PSEUDO_NOERRNO (SYMBOL, NAME, N)
-#define T_PSEUDO_ERRVAL(SYMBOL, NAME, N) PSEUDO_ERRVAL (SYMBOL, NAME, N)
+/* If PSEUDOS_HAVE_ULONG_INDICES is defined, PSEUDO and T_PSEUDO macros
+ have 2 extra arguments for unsigned long int arguments:
+ Extra argument 1: Position of the first unsigned long int argument.
+ Extra argument 2: Position of the second unsigned long int argument.
+ */
+#ifndef PSEUDOS_HAVE_ULONG_INDICES
+# undef SYSCALL_ULONG_ARG_1
+# define SYSCALL_ULONG_ARG_1 0
+#endif
+
+#if SYSCALL_ULONG_ARG_1
+# define T_PSEUDO(SYMBOL, NAME, N, U1, U2) \
+ PSEUDO (SYMBOL, NAME, N, U1, U2)
+# define T_PSEUDO_NOERRNO(SYMBOL, NAME, N, U1, U2) \
+ PSEUDO_NOERRNO (SYMBOL, NAME, N, U1, U2)
+# define T_PSEUDO_ERRVAL(SYMBOL, NAME, N, U1, U2) \
+ PSEUDO_ERRVAL (SYMBOL, NAME, N, U1, U2)
+#else
+# define T_PSEUDO(SYMBOL, NAME, N) \
+ PSEUDO (SYMBOL, NAME, N)
+# define T_PSEUDO_NOERRNO(SYMBOL, NAME, N) \
+ PSEUDO_NOERRNO (SYMBOL, NAME, N)
+# define T_PSEUDO_ERRVAL(SYMBOL, NAME, N) \
+ PSEUDO_ERRVAL (SYMBOL, NAME, N)
+#endif
#define T_PSEUDO_END(SYMBOL) PSEUDO_END (SYMBOL)
#define T_PSEUDO_END_NOERRNO(SYMBOL) PSEUDO_END_NOERRNO (SYMBOL)
#define T_PSEUDO_END_ERRVAL(SYMBOL) PSEUDO_END_ERRVAL (SYMBOL)
@@ -56,7 +84,12 @@
/* This kind of system call stub never returns an error.
We return the return value register to the caller unexamined. */
+# if SYSCALL_ULONG_ARG_1
+T_PSEUDO_NOERRNO (SYSCALL_SYMBOL, SYSCALL_NAME, SYSCALL_NARGS,
+ SYSCALL_ULONG_ARG_1, SYSCALL_ULONG_ARG_2)
+# else
T_PSEUDO_NOERRNO (SYSCALL_SYMBOL, SYSCALL_NAME, SYSCALL_NARGS)
+# endif
ret_NOERRNO
T_PSEUDO_END_NOERRNO (SYSCALL_SYMBOL)
@@ -66,7 +99,12 @@ T_PSEUDO_END_NOERRNO (SYSCALL_SYMBOL)
value, or zero for success. We may massage the kernel's return value
to meet that ABI, but we never set errno here. */
+# if SYSCALL_ULONG_ARG_1
+T_PSEUDO_ERRVAL (SYSCALL_SYMBOL, SYSCALL_NAME, SYSCALL_NARGS,
+ SYSCALL_ULONG_ARG_1, SYSCALL_ULONG_ARG_2)
+# else
T_PSEUDO_ERRVAL (SYSCALL_SYMBOL, SYSCALL_NAME, SYSCALL_NARGS)
+# endif
ret_ERRVAL
T_PSEUDO_END_ERRVAL (SYSCALL_SYMBOL)
@@ -75,7 +113,12 @@ T_PSEUDO_END_ERRVAL (SYSCALL_SYMBOL)
/* This is a "normal" system call stub: if there is an error,
it returns -1 and sets errno. */
+# if SYSCALL_ULONG_ARG_1
+T_PSEUDO (SYSCALL_SYMBOL, SYSCALL_NAME, SYSCALL_NARGS,
+ SYSCALL_ULONG_ARG_1, SYSCALL_ULONG_ARG_2)
+# else
T_PSEUDO (SYSCALL_SYMBOL, SYSCALL_NAME, SYSCALL_NARGS)
+# endif
ret
T_PSEUDO_END (SYSCALL_SYMBOL)
diff --git a/sysdeps/unix/syscalls.list b/sysdeps/unix/syscalls.list
index e28e801c7a..5ca991acbf 100644
--- a/sysdeps/unix/syscalls.list
+++ b/sysdeps/unix/syscalls.list
@@ -39,16 +39,16 @@ kill - kill i:ii __kill kill
link - link i:ss __link link
listen - listen i:ii __listen listen
lseek - lseek i:iii __libc_lseek __lseek lseek
-madvise - madvise i:pii __madvise madvise
+madvise - madvise i:pUi __madvise madvise
mkdir - mkdir i:si __mkdir mkdir
mmap - mmap b:aniiii __mmap mmap
-mprotect - mprotect i:aii __mprotect mprotect
-munmap - munmap i:ai __munmap munmap
+mprotect - mprotect i:aUi __mprotect mprotect
+munmap - munmap i:aU __munmap munmap
open - open Ci:siv __libc_open __open open
profil - profil i:piii __profil profil
ptrace - ptrace i:iiii ptrace
read - read Ci:ibn __libc_read __read read
-readlink - readlink i:spi __readlink readlink
+readlink - readlink i:spU __readlink readlink
readv - readv Ci:ipi __readv readv
reboot - reboot i:i reboot
recv - recv Ci:ibni __libc_recv recv
diff --git a/sysdeps/unix/sysv/linux/syscalls.list b/sysdeps/unix/sysv/linux/syscalls.list
index 5f1352ad43..e8d55c8ce0 100644
--- a/sysdeps/unix/sysv/linux/syscalls.list
+++ b/sysdeps/unix/sysv/linux/syscalls.list
@@ -32,12 +32,12 @@ ioperm - ioperm i:iii ioperm
iopl - iopl i:i iopl
klogctl EXTRA syslog i:isi klogctl
lchown - lchown i:sii __lchown lchown
-mincore - mincore i:anV mincore
-mlock - mlock i:bn mlock
+mincore - mincore i:aUV mincore
+mlock - mlock i:bU mlock
mlockall - mlockall i:i mlockall
-mount EXTRA mount i:sssip __mount mount
-mremap EXTRA mremap b:ainip __mremap mremap
-munlock - munlock i:ai munlock
+mount EXTRA mount i:sssUp __mount mount
+mremap EXTRA mremap b:aUUip __mremap mremap
+munlock - munlock i:aU munlock
munlockall - munlockall i: munlockall
nfsservctl EXTRA nfsservctl i:ipp __compat_nfsservctl nfsservctl@GLIBC_2.0:GLIBC_2.28
pipe - pipe i:f __pipe pipe
@@ -46,7 +46,7 @@ pivot_root EXTRA pivot_root i:ss pivot_root
prctl EXTRA prctl i:iiiii __prctl prctl
query_module EXTRA query_module i:sipip __compat_query_module query_module@GLIBC_2.0:GLIBC_2.23
quotactl EXTRA quotactl i:isip quotactl
-remap_file_pages - remap_file_pages i:piiii __remap_file_pages remap_file_pages
+remap_file_pages - remap_file_pages i:pUiUi __remap_file_pages remap_file_pages
sched_getp - sched_getparam i:ip __sched_getparam sched_getparam
sched_gets - sched_getscheduler i:i __sched_getscheduler sched_getscheduler
sched_primax - sched_get_priority_max i:i __sched_get_priority_max sched_get_priority_max
@@ -55,7 +55,7 @@ sched_rr_gi - sched_rr_get_interval i:ip __sched_rr_get_interval sched_rr_get_in
sched_setp - sched_setparam i:ip __sched_setparam sched_setparam
sched_sets - sched_setscheduler i:iip __sched_setscheduler sched_setscheduler
sched_yield - sched_yield i: __sched_yield sched_yield
-sendfile - sendfile i:iipi sendfile
+sendfile - sendfile i:iipU sendfile
sendfile64 - sendfile64 i:iipi sendfile64
setfsgid EXTRA setfsgid i:i setfsgid
setfsuid EXTRA setfsuid i:i setfsuid
@@ -73,7 +73,7 @@ chown - chown i:sii __libc_chown __chown chown
fchownat - fchownat i:isiii fchownat
linkat - linkat i:isisi linkat
mkdirat - mkdirat i:isi mkdirat
-readlinkat - readlinkat i:issi readlinkat
+readlinkat - readlinkat i:issU readlinkat
symlinkat - symlinkat i:sis symlinkat
unlinkat - unlinkat i:isi unlinkat
diff --git a/sysdeps/unix/sysv/linux/x86_64/sysdep.h b/sysdeps/unix/sysv/linux/x86_64/sysdep.h
index 7c60a3a134..c7f740a1df 100644
--- a/sysdeps/unix/sysv/linux/x86_64/sysdep.h
+++ b/sysdeps/unix/sysv/linux/x86_64/sysdep.h
@@ -61,13 +61,31 @@
# define SYSCALL_ERROR_LABEL syscall_error
# endif
+/* PSEUDO and T_PSEUDO macros have 2 extra arguments for unsigned long
+ int arguments. */
+# define PSEUDOS_HAVE_ULONG_INDICES 1
+
+# ifndef SYSCALL_ULONG_ARG_1
+# define SYSCALL_ULONG_ARG_1 0
+# define SYSCALL_ULONG_ARG_2 0
+# endif
+
# undef PSEUDO
-# define PSEUDO(name, syscall_name, args) \
- .text; \
- ENTRY (name) \
- DO_CALL (syscall_name, args); \
- cmpq $-4095, %rax; \
+# if SYSCALL_ULONG_ARG_1
+# define PSEUDO(name, syscall_name, args, ulong_arg_1, ulong_arg_2) \
+ .text; \
+ ENTRY (name) \
+ DO_CALL (syscall_name, args, ulong_arg_1, ulong_arg_2); \
+ cmpq $-4095, %rax; \
jae SYSCALL_ERROR_LABEL
+# else
+# define PSEUDO(name, syscall_name, args) \
+ .text; \
+ ENTRY (name) \
+ DO_CALL (syscall_name, args, 0, 0); \
+ cmpq $-4095, %rax; \
+ jae SYSCALL_ERROR_LABEL
+# endif
# undef PSEUDO_END
# define PSEUDO_END(name) \
@@ -75,10 +93,17 @@
END (name)
# undef PSEUDO_NOERRNO
-# define PSEUDO_NOERRNO(name, syscall_name, args) \
- .text; \
- ENTRY (name) \
- DO_CALL (syscall_name, args)
+# if SYSCALL_ULONG_ARG_1
+# define PSEUDO_NOERRNO(name, syscall_name, args, ulong_arg_1, ulong_arg_2) \
+ .text; \
+ ENTRY (name) \
+ DO_CALL (syscall_name, args, ulong_arg_1, ulong_arg_2)
+# else
+# define PSEUDO_NOERRNO(name, syscall_name, args) \
+ .text; \
+ ENTRY (name) \
+ DO_CALL (syscall_name, args, 0, 0)
+# endif
# undef PSEUDO_END_NOERRNO
# define PSEUDO_END_NOERRNO(name) \
@@ -87,11 +112,19 @@
# define ret_NOERRNO ret
# undef PSEUDO_ERRVAL
-# define PSEUDO_ERRVAL(name, syscall_name, args) \
- .text; \
- ENTRY (name) \
- DO_CALL (syscall_name, args); \
+# if SYSCALL_ULONG_ARG_1
+# define PSEUDO_ERRVAL(name, syscall_name, args, ulong_arg_1, ulong_arg_2) \
+ .text; \
+ ENTRY (name) \
+ DO_CALL (syscall_name, args, ulong_arg_1, ulong_arg_2); \
+ negq %rax
+# else
+# define PSEUDO_ERRVAL(name, syscall_name, args) \
+ .text; \
+ ENTRY (name) \
+ DO_CALL (syscall_name, args, 0, 0); \
negq %rax
+# endif
# undef PSEUDO_END_ERRVAL
# define PSEUDO_END_ERRVAL(name) \
@@ -163,8 +196,10 @@
Syscalls of more than 6 arguments are not supported. */
# undef DO_CALL
-# define DO_CALL(syscall_name, args) \
+# define DO_CALL(syscall_name, args, ulong_arg_1, ulong_arg_2) \
DOARGS_##args \
+ ZERO_EXTEND_##ulong_arg_1 \
+ ZERO_EXTEND_##ulong_arg_2 \
movl $SYS_ify (syscall_name), %eax; \
syscall;
@@ -176,6 +211,14 @@
# define DOARGS_5 DOARGS_4
# define DOARGS_6 DOARGS_5
+# define ZERO_EXTEND_0 /* nothing */
+# define ZERO_EXTEND_1 /* nothing */
+# define ZERO_EXTEND_2 /* nothing */
+# define ZERO_EXTEND_3 /* nothing */
+# define ZERO_EXTEND_4 /* nothing */
+# define ZERO_EXTEND_5 /* nothing */
+# define ZERO_EXTEND_6 /* nothing */
+
#else /* !__ASSEMBLER__ */
/* Define a macro which expands inline into the wrapper code for a system
call. */
diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/sysdep.h b/sysdeps/unix/sysv/linux/x86_64/x32/sysdep.h
index a37d520f86..62e6f8fe11 100644
--- a/sysdeps/unix/sysv/linux/x86_64/x32/sysdep.h
+++ b/sysdeps/unix/sysv/linux/x86_64/x32/sysdep.h
@@ -26,7 +26,26 @@
#undef LO_HI_LONG
#define LO_HI_LONG(val) (val)
-#ifndef __ASSEMBLER__
+#ifdef __ASSEMBLER__
+/* Zero-extend 32-bit unsigned long int arguments to 64 bits. */
+# undef ZERO_EXTEND_1
+# define ZERO_EXTEND_1 movl %edi, %edi;
+# undef ZERO_EXTEND_2
+# define ZERO_EXTEND_2 movl %esi, %esi;
+# undef ZERO_EXTEND_3
+# define ZERO_EXTEND_3 movl %edx, %edx;
+# if SYSCALL_ULONG_ARG_1 == 4 || SYSCALL_ULONG_ARG_2 == 4
+# undef DOARGS_4
+# define DOARGS_4 movl %ecx, %r10d;
+# else
+# undef ZERO_EXTEND_4
+# define ZERO_EXTEND_4 movl %r10d, %r10d;
+# endif
+# undef ZERO_EXTEND_5
+# define ZERO_EXTEND_5 movl %r8d, %r8d;
+# undef ZERO_EXTEND_6
+# define ZERO_EXTEND_6 movl %r9d, %r9d;
+#else /* !__ASSEMBLER__ */
# undef ARGIFY
/* Enforce zero-extension for pointers and array system call arguments.
For integer types, extend to int64_t (the full register) using a
--
2.26.2
next prev parent reply other threads:[~2020-04-30 19:34 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-04-30 19:34 [2.31/2.30] [PATCH 0/6] Properly pass long to syscall [BZ #25810/#25896] H.J. Lu
2020-04-30 19:34 ` [2.31/2.30] [PATCH 1/6] x32: Properly pass long to syscall [BZ #25810] H.J. Lu
2020-04-30 19:34 ` H.J. Lu [this message]
2020-04-30 19:34 ` [2.31/2.30] [PATCH 3/6] Add a syscall test for " H.J. Lu
2020-04-30 19:34 ` [2.31/2.30] [PATCH 4/6] Mark unsigned long arguments with U in more syscalls " H.J. Lu
2020-04-30 19:34 ` [2.31/2.30] [PATCH 5/6] Add C wrappers for process_vm_readv/process_vm_writev " H.J. Lu
2020-04-30 19:34 ` [2.31/2.30] [PATCH 6/6] Add a C wrapper for prctl [BZ #25896] H.J. Lu
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