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* [glibc/azanella/bz12683] nptl: x86_64: Fix Race conditions in pthread cancellation (BZ#12683)
@ 2019-08-19 20:35 Adhemerval Zanella
0 siblings, 0 replies; 4+ messages in thread
From: Adhemerval Zanella @ 2019-08-19 20:35 UTC (permalink / raw)
To: glibc-cvs
https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=d39ceb32d8e0b283ee816c0a90adc84f6a16a5c2
commit d39ceb32d8e0b283ee816c0a90adc84f6a16a5c2
Author: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Date: Mon Sep 29 09:48:34 2014 -0300
nptl: x86_64: Fix Race conditions in pthread cancellation (BZ#12683)
This patches adds the x86_64 modification required for the BZ#12683.
The arch-specific {libc-,librt-}cancelation.S files are remove in favor
of the default libc-cancellation implementation, the TCB_CANCELING_BITMASK
is remove since it is now unused, and the arch-specific syscall_cancel
is provided.
Checked on x86_64-linux-gnu.
[BZ #12683]
* sysdeps/unix/sysv/linux/x86_64/cancellation.S: Remove file.
* sysdeps/unix/sysv/linux/x86_64/libc-cancellation.S: Remove file.
* sysdeps/unix/sysv/linux/x86_64/librt-cancellation.S: Remove file.
* sysdeps/x86_64/nptl/tcb-offsets.sym (TCB_CANCELING_BITMASK):
Remove.
* sysdeps/unix/sysv/linux/x86_64/syscall_cancel.S: New file.
Diff:
---
sysdeps/unix/sysv/linux/x86_64/cancellation.S | 104 ---------------------
sysdeps/unix/sysv/linux/x86_64/libc-cancellation.S | 21 -----
.../unix/sysv/linux/x86_64/librt-cancellation.S | 21 -----
sysdeps/unix/sysv/linux/x86_64/syscall_cancel.S | 61 ++++++++++++
sysdeps/x86_64/nptl/tcb-offsets.sym | 1 -
5 files changed, 61 insertions(+), 147 deletions(-)
diff --git a/sysdeps/unix/sysv/linux/x86_64/cancellation.S b/sysdeps/unix/sysv/linux/x86_64/cancellation.S
deleted file mode 100644
index bb49107..0000000
--- a/sysdeps/unix/sysv/linux/x86_64/cancellation.S
+++ /dev/null
@@ -1,104 +0,0 @@
-/* Copyright (C) 2009-2019 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
- Contributed by Ulrich Drepper <drepper@redhat.com>, 2009.
-
- The GNU C Library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Lesser General Public
- License as published by the Free Software Foundation; either
- version 2.1 of the License, or (at your option) any later version.
-
- The GNU C 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
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public
- License along with the GNU C Library; if not, see
- <http://www.gnu.org/licenses/>. */
-
-#include <sysdep.h>
-#include <tcb-offsets.h>
-#include <kernel-features.h>
-#include <lowlevellock-futex.h>
-
-#define PTHREAD_UNWIND JUMPTARGET(__pthread_unwind)
-#if IS_IN (libpthread)
-# if defined SHARED && !defined NO_HIDDEN
-# undef PTHREAD_UNWIND
-# define PTHREAD_UNWIND __GI___pthread_unwind
-# endif
-#else
-# ifndef SHARED
- .weak __pthread_unwind
-# endif
-#endif
-
-
-#define LOAD_PRIVATE_FUTEX_WAIT(reg) \
- movl $(FUTEX_WAIT | FUTEX_PRIVATE_FLAG), reg
-
-/* It is crucial that the functions in this file don't modify registers
- other than %rax and %r11. The syscall wrapper code depends on this
- because it doesn't explicitly save the other registers which hold
- relevant values. */
- .text
-
- .hidden __pthread_enable_asynccancel
-ENTRY(__pthread_enable_asynccancel)
- movl %fs:CANCELHANDLING, %eax
-2: movl %eax, %r11d
- orl $TCB_CANCELTYPE_BITMASK, %r11d
- cmpl %eax, %r11d
- je 1f
-
- lock
- cmpxchgl %r11d, %fs:CANCELHANDLING
- jnz 2b
-
- andl $(TCB_CANCELSTATE_BITMASK|TCB_CANCELTYPE_BITMASK|TCB_CANCELED_BITMASK|TCB_EXITING_BITMASK|TCB_CANCEL_RESTMASK|TCB_TERMINATED_BITMASK), %r11d
- cmpl $(TCB_CANCELTYPE_BITMASK|TCB_CANCELED_BITMASK), %r11d
- je 3f
-
-1: ret
-
-3: subq $8, %rsp
- cfi_adjust_cfa_offset(8)
- LP_OP(mov) $TCB_PTHREAD_CANCELED, %fs:RESULT
- lock
- orl $TCB_EXITING_BITMASK, %fs:CANCELHANDLING
- mov %fs:CLEANUP_JMP_BUF, %RDI_LP
- call PTHREAD_UNWIND
- hlt
-END(__pthread_enable_asynccancel)
-
-
- .hidden __pthread_disable_asynccancel
-ENTRY(__pthread_disable_asynccancel)
- testl $TCB_CANCELTYPE_BITMASK, %edi
- jnz 1f
-
- movl %fs:CANCELHANDLING, %eax
-2: movl %eax, %r11d
- andl $~TCB_CANCELTYPE_BITMASK, %r11d
- lock
- cmpxchgl %r11d, %fs:CANCELHANDLING
- jnz 2b
-
- movl %r11d, %eax
-3: andl $(TCB_CANCELING_BITMASK|TCB_CANCELED_BITMASK), %eax
- cmpl $TCB_CANCELING_BITMASK, %eax
- je 4f
-1: ret
-
- /* Performance doesn't matter in this loop. We will
- delay until the thread is canceled. And we will unlikely
- enter the loop twice. */
-4: mov %fs:0, %RDI_LP
- movl $__NR_futex, %eax
- xorq %r10, %r10
- addq $CANCELHANDLING, %rdi
- LOAD_PRIVATE_FUTEX_WAIT (%esi)
- syscall
- movl %fs:CANCELHANDLING, %eax
- jmp 3b
-END(__pthread_disable_asynccancel)
diff --git a/sysdeps/unix/sysv/linux/x86_64/libc-cancellation.S b/sysdeps/unix/sysv/linux/x86_64/libc-cancellation.S
deleted file mode 100644
index 5ecc10d..0000000
--- a/sysdeps/unix/sysv/linux/x86_64/libc-cancellation.S
+++ /dev/null
@@ -1,21 +0,0 @@
-/* Copyright (C) 2009-2019 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
- Contributed by Ulrich Drepper <drepper@redhat.com>, 2009.
-
- The GNU C Library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Lesser General Public
- License as published by the Free Software Foundation; either
- version 2.1 of the License, or (at your option) any later version.
-
- The GNU C 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
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public
- License along with the GNU C Library; if not, see
- <http://www.gnu.org/licenses/>. */
-
-#define __pthread_enable_asynccancel __libc_enable_asynccancel
-#define __pthread_disable_asynccancel __libc_disable_asynccancel
-#include "cancellation.S"
diff --git a/sysdeps/unix/sysv/linux/x86_64/librt-cancellation.S b/sysdeps/unix/sysv/linux/x86_64/librt-cancellation.S
deleted file mode 100644
index df2ebd0..0000000
--- a/sysdeps/unix/sysv/linux/x86_64/librt-cancellation.S
+++ /dev/null
@@ -1,21 +0,0 @@
-/* Copyright (C) 2009-2019 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
- Contributed by Ulrich Drepper <drepper@redhat.com>, 2009.
-
- The GNU C Library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Lesser General Public
- License as published by the Free Software Foundation; either
- version 2.1 of the License, or (at your option) any later version.
-
- The GNU C 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
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public
- License along with the GNU C Library; if not, see
- <http://www.gnu.org/licenses/>. */
-
-#define __pthread_enable_asynccancel __librt_enable_asynccancel
-#define __pthread_disable_asynccancel __librt_disable_asynccancel
-#include "cancellation.S"
diff --git a/sysdeps/unix/sysv/linux/x86_64/syscall_cancel.S b/sysdeps/unix/sysv/linux/x86_64/syscall_cancel.S
new file mode 100644
index 0000000..c7364bf
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/x86_64/syscall_cancel.S
@@ -0,0 +1,61 @@
+/* Cancellable syscall wrapper - x86_64 version.
+ Copyright (C) 2019 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#include <sysdep.h>
+
+/* long int [rax] __syscall_cancel_arch (volatile int *cancelhandling [%rdi],
+ __syscall_arg_t nr [%rsi],
+ __syscall_arg_t arg1 [%rdx],
+ __syscall_arg_t arg2 [%rcx],
+ __syscall_arg_t arg3 [%r8],
+ __syscall_arg_t arg4 [%r9],
+ __syscall_arg_t arg5 [SP+8],
+ __syscall_arg_t arg6 [SP+16]) */
+
+ENTRY (__syscall_cancel_arch)
+
+ .globl __syscall_cancel_arch_start
+ .type __syscall_cancel_arch_start,@function
+__syscall_cancel_arch_start:
+
+ /* if (*cancelhandling & CANCELED_BITMASK)
+ __syscall_do_cancel() */
+ mov (%rdi),%eax
+ testb $4, (%rdi)
+ jne __syscall_do_cancel
+
+ /* Issue a 6 argument syscall, the nr [%rax] being the syscall
+ number. */
+ mov %rdi,%r11
+ mov %rsi,%rax
+ mov %rdx,%rdi
+ mov %rcx,%rsi
+ mov %r8,%rdx
+ mov %r9,%r10
+ mov 8(%rsp),%r8
+ mov 16(%rsp),%r9
+ mov %r11,8(%rsp)
+ syscall
+
+ .globl __syscall_cancel_arch_end
+ .type __syscall_cancel_arch_end,@function
+__syscall_cancel_arch_end:
+ ret
+
+END (__syscall_cancel_arch)
+libc_hidden_def (__syscall_cancel_arch)
diff --git a/sysdeps/x86_64/nptl/tcb-offsets.sym b/sysdeps/x86_64/nptl/tcb-offsets.sym
index ae80347..5d033d1 100644
--- a/sysdeps/x86_64/nptl/tcb-offsets.sym
+++ b/sysdeps/x86_64/nptl/tcb-offsets.sym
@@ -18,7 +18,6 @@ SSP_BASE_OFFSET offsetof (tcbhead_t, ssp_base)
-- Not strictly offsets, but these values are also used in the TCB.
TCB_CANCELSTATE_BITMASK CANCELSTATE_BITMASK
TCB_CANCELTYPE_BITMASK CANCELTYPE_BITMASK
-TCB_CANCELING_BITMASK CANCELING_BITMASK
TCB_CANCELED_BITMASK CANCELED_BITMASK
TCB_EXITING_BITMASK EXITING_BITMASK
TCB_CANCEL_RESTMASK CANCEL_RESTMASK
^ permalink raw reply [flat|nested] 4+ messages in thread
* [glibc/azanella/bz12683] nptl: x86_64: Fix Race conditions in pthread cancellation [BZ#12683]
@ 2020-04-07 14:03 Adhemerval Zanella
0 siblings, 0 replies; 4+ messages in thread
From: Adhemerval Zanella @ 2020-04-07 14:03 UTC (permalink / raw)
To: glibc-cvs
https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=57e4b8e6c1acf454d8938cd99d4764a27fa77b60
commit 57e4b8e6c1acf454d8938cd99d4764a27fa77b60
Author: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Date: Mon Sep 29 09:48:34 2014 -0300
nptl: x86_64: Fix Race conditions in pthread cancellation [BZ#12683]
This patches adds the x86_64 modification required for the BZ#12683.
Checked on x86_64-linux-gnu.
Diff:
---
sysdeps/unix/sysv/linux/x86_64/syscall_cancel.S | 59 +++++++++++++++++++++++++
1 file changed, 59 insertions(+)
diff --git a/sysdeps/unix/sysv/linux/x86_64/syscall_cancel.S b/sysdeps/unix/sysv/linux/x86_64/syscall_cancel.S
new file mode 100644
index 0000000000..11c3eeb084
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/x86_64/syscall_cancel.S
@@ -0,0 +1,59 @@
+/* Cancellable syscall wrapper - x86_64 version.
+ Copyright (C) 2020 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#include <sysdep.h>
+
+/* long int [rax] __syscall_cancel_arch (volatile int *cancelhandling [%rdi],
+ __syscall_arg_t nr [%rsi],
+ __syscall_arg_t arg1 [%rdx],
+ __syscall_arg_t arg2 [%rcx],
+ __syscall_arg_t arg3 [%r8],
+ __syscall_arg_t arg4 [%r9],
+ __syscall_arg_t arg5 [SP+8],
+ __syscall_arg_t arg6 [SP+16]) */
+
+ENTRY (__syscall_cancel_arch)
+
+ .globl __syscall_cancel_arch_start
+__syscall_cancel_arch_start:
+
+ /* if (*cancelhandling & CANCELED_BITMASK)
+ __syscall_do_cancel() */
+ mov (%rdi),%eax
+ testb $TCB_CANCELED_BITMASK, (%rdi)
+ jne __syscall_do_cancel
+
+ /* Issue a 6 argument syscall, the nr [%rax] being the syscall
+ number. */
+ mov %rdi,%r11
+ mov %rsi,%rax
+ mov %rdx,%rdi
+ mov %rcx,%rsi
+ mov %r8,%rdx
+ mov %r9,%r10
+ mov 8(%rsp),%r8
+ mov 16(%rsp),%r9
+ mov %r11,8(%rsp)
+ syscall
+
+ .globl __syscall_cancel_arch_end
+__syscall_cancel_arch_end:
+ ret
+
+END (__syscall_cancel_arch)
+libc_hidden_def (__syscall_cancel_arch)
^ permalink raw reply [flat|nested] 4+ messages in thread
* [glibc/azanella/bz12683] nptl: x86_64: Fix Race conditions in pthread cancellation [BZ#12683]
@ 2020-04-03 20:23 Adhemerval Zanella
0 siblings, 0 replies; 4+ messages in thread
From: Adhemerval Zanella @ 2020-04-03 20:23 UTC (permalink / raw)
To: glibc-cvs
https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=6426c97b25270ec2b72cd732522439cdb3b19333
commit 6426c97b25270ec2b72cd732522439cdb3b19333
Author: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Date: Mon Sep 29 09:48:34 2014 -0300
nptl: x86_64: Fix Race conditions in pthread cancellation [BZ#12683]
This patches adds the x86_64 modification required for the BZ#12683.
Checked on x86_64-linux-gnu.
Diff:
---
sysdeps/unix/sysv/linux/x86_64/syscall_cancel.S | 59 +++++++++++++++++++++++++
1 file changed, 59 insertions(+)
diff --git a/sysdeps/unix/sysv/linux/x86_64/syscall_cancel.S b/sysdeps/unix/sysv/linux/x86_64/syscall_cancel.S
new file mode 100644
index 0000000000..11c3eeb084
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/x86_64/syscall_cancel.S
@@ -0,0 +1,59 @@
+/* Cancellable syscall wrapper - x86_64 version.
+ Copyright (C) 2020 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#include <sysdep.h>
+
+/* long int [rax] __syscall_cancel_arch (volatile int *cancelhandling [%rdi],
+ __syscall_arg_t nr [%rsi],
+ __syscall_arg_t arg1 [%rdx],
+ __syscall_arg_t arg2 [%rcx],
+ __syscall_arg_t arg3 [%r8],
+ __syscall_arg_t arg4 [%r9],
+ __syscall_arg_t arg5 [SP+8],
+ __syscall_arg_t arg6 [SP+16]) */
+
+ENTRY (__syscall_cancel_arch)
+
+ .globl __syscall_cancel_arch_start
+__syscall_cancel_arch_start:
+
+ /* if (*cancelhandling & CANCELED_BITMASK)
+ __syscall_do_cancel() */
+ mov (%rdi),%eax
+ testb $TCB_CANCELED_BITMASK, (%rdi)
+ jne __syscall_do_cancel
+
+ /* Issue a 6 argument syscall, the nr [%rax] being the syscall
+ number. */
+ mov %rdi,%r11
+ mov %rsi,%rax
+ mov %rdx,%rdi
+ mov %rcx,%rsi
+ mov %r8,%rdx
+ mov %r9,%r10
+ mov 8(%rsp),%r8
+ mov 16(%rsp),%r9
+ mov %r11,8(%rsp)
+ syscall
+
+ .globl __syscall_cancel_arch_end
+__syscall_cancel_arch_end:
+ ret
+
+END (__syscall_cancel_arch)
+libc_hidden_def (__syscall_cancel_arch)
^ permalink raw reply [flat|nested] 4+ messages in thread
* [glibc/azanella/bz12683] nptl: x86_64: Fix Race conditions in pthread cancellation (BZ#12683)
@ 2019-10-17 13:57 Adhemerval Zanella
0 siblings, 0 replies; 4+ messages in thread
From: Adhemerval Zanella @ 2019-10-17 13:57 UTC (permalink / raw)
To: glibc-cvs
https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=67911f4199774950c4b08def038c17f567032735
commit 67911f4199774950c4b08def038c17f567032735
Author: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Date: Mon Sep 29 09:48:34 2014 -0300
nptl: x86_64: Fix Race conditions in pthread cancellation (BZ#12683)
This patches adds the x86_64 modification required for the BZ#12683.
The arch-specific {libc-,librt-}cancelation.S files are remove in favor
of the default libc-cancellation implementation, the
TCB_CANCELING_BITMASK is remove since it is now unused, and the
arch-specific syscall_cancel is provided.
Checked on x86_64-linux-gnu.
Diff:
---
sysdeps/unix/sysv/linux/x86_64/cancellation.S | 104 ---------------------
sysdeps/unix/sysv/linux/x86_64/libc-cancellation.S | 21 -----
.../unix/sysv/linux/x86_64/librt-cancellation.S | 21 -----
sysdeps/unix/sysv/linux/x86_64/syscall_cancel.S | 59 ++++++++++++
sysdeps/x86_64/nptl/tcb-offsets.sym | 11 +--
5 files changed, 61 insertions(+), 155 deletions(-)
diff --git a/sysdeps/unix/sysv/linux/x86_64/cancellation.S b/sysdeps/unix/sysv/linux/x86_64/cancellation.S
deleted file mode 100644
index f8a142d..0000000
--- a/sysdeps/unix/sysv/linux/x86_64/cancellation.S
+++ /dev/null
@@ -1,104 +0,0 @@
-/* Copyright (C) 2009-2019 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
- Contributed by Ulrich Drepper <drepper@redhat.com>, 2009.
-
- The GNU C Library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Lesser General Public
- License as published by the Free Software Foundation; either
- version 2.1 of the License, or (at your option) any later version.
-
- The GNU C 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
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public
- License along with the GNU C Library; if not, see
- <https://www.gnu.org/licenses/>. */
-
-#include <sysdep.h>
-#include <tcb-offsets.h>
-#include <kernel-features.h>
-#include <lowlevellock-futex.h>
-
-#define PTHREAD_UNWIND JUMPTARGET(__pthread_unwind)
-#if IS_IN (libpthread)
-# if defined SHARED && !defined NO_HIDDEN
-# undef PTHREAD_UNWIND
-# define PTHREAD_UNWIND __GI___pthread_unwind
-# endif
-#else
-# ifndef SHARED
- .weak __pthread_unwind
-# endif
-#endif
-
-
-#define LOAD_PRIVATE_FUTEX_WAIT(reg) \
- movl $(FUTEX_WAIT | FUTEX_PRIVATE_FLAG), reg
-
-/* It is crucial that the functions in this file don't modify registers
- other than %rax and %r11. The syscall wrapper code depends on this
- because it doesn't explicitly save the other registers which hold
- relevant values. */
- .text
-
- .hidden __pthread_enable_asynccancel
-ENTRY(__pthread_enable_asynccancel)
- movl %fs:CANCELHANDLING, %eax
-2: movl %eax, %r11d
- orl $TCB_CANCELTYPE_BITMASK, %r11d
- cmpl %eax, %r11d
- je 1f
-
- lock
- cmpxchgl %r11d, %fs:CANCELHANDLING
- jnz 2b
-
- andl $(TCB_CANCELSTATE_BITMASK|TCB_CANCELTYPE_BITMASK|TCB_CANCELED_BITMASK|TCB_EXITING_BITMASK|TCB_CANCEL_RESTMASK|TCB_TERMINATED_BITMASK), %r11d
- cmpl $(TCB_CANCELTYPE_BITMASK|TCB_CANCELED_BITMASK), %r11d
- je 3f
-
-1: ret
-
-3: subq $8, %rsp
- cfi_adjust_cfa_offset(8)
- LP_OP(mov) $TCB_PTHREAD_CANCELED, %fs:RESULT
- lock
- orl $TCB_EXITING_BITMASK, %fs:CANCELHANDLING
- mov %fs:CLEANUP_JMP_BUF, %RDI_LP
- call PTHREAD_UNWIND
- hlt
-END(__pthread_enable_asynccancel)
-
-
- .hidden __pthread_disable_asynccancel
-ENTRY(__pthread_disable_asynccancel)
- testl $TCB_CANCELTYPE_BITMASK, %edi
- jnz 1f
-
- movl %fs:CANCELHANDLING, %eax
-2: movl %eax, %r11d
- andl $~TCB_CANCELTYPE_BITMASK, %r11d
- lock
- cmpxchgl %r11d, %fs:CANCELHANDLING
- jnz 2b
-
- movl %r11d, %eax
-3: andl $(TCB_CANCELING_BITMASK|TCB_CANCELED_BITMASK), %eax
- cmpl $TCB_CANCELING_BITMASK, %eax
- je 4f
-1: ret
-
- /* Performance doesn't matter in this loop. We will
- delay until the thread is canceled. And we will unlikely
- enter the loop twice. */
-4: mov %fs:0, %RDI_LP
- movl $__NR_futex, %eax
- xorq %r10, %r10
- addq $CANCELHANDLING, %rdi
- LOAD_PRIVATE_FUTEX_WAIT (%esi)
- syscall
- movl %fs:CANCELHANDLING, %eax
- jmp 3b
-END(__pthread_disable_asynccancel)
diff --git a/sysdeps/unix/sysv/linux/x86_64/libc-cancellation.S b/sysdeps/unix/sysv/linux/x86_64/libc-cancellation.S
deleted file mode 100644
index cf8da66..0000000
--- a/sysdeps/unix/sysv/linux/x86_64/libc-cancellation.S
+++ /dev/null
@@ -1,21 +0,0 @@
-/* Copyright (C) 2009-2019 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
- Contributed by Ulrich Drepper <drepper@redhat.com>, 2009.
-
- The GNU C Library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Lesser General Public
- License as published by the Free Software Foundation; either
- version 2.1 of the License, or (at your option) any later version.
-
- The GNU C 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
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public
- License along with the GNU C Library; if not, see
- <https://www.gnu.org/licenses/>. */
-
-#define __pthread_enable_asynccancel __libc_enable_asynccancel
-#define __pthread_disable_asynccancel __libc_disable_asynccancel
-#include "cancellation.S"
diff --git a/sysdeps/unix/sysv/linux/x86_64/librt-cancellation.S b/sysdeps/unix/sysv/linux/x86_64/librt-cancellation.S
deleted file mode 100644
index e7dcc61..0000000
--- a/sysdeps/unix/sysv/linux/x86_64/librt-cancellation.S
+++ /dev/null
@@ -1,21 +0,0 @@
-/* Copyright (C) 2009-2019 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
- Contributed by Ulrich Drepper <drepper@redhat.com>, 2009.
-
- The GNU C Library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Lesser General Public
- License as published by the Free Software Foundation; either
- version 2.1 of the License, or (at your option) any later version.
-
- The GNU C 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
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public
- License along with the GNU C Library; if not, see
- <https://www.gnu.org/licenses/>. */
-
-#define __pthread_enable_asynccancel __librt_enable_asynccancel
-#define __pthread_disable_asynccancel __librt_disable_asynccancel
-#include "cancellation.S"
diff --git a/sysdeps/unix/sysv/linux/x86_64/syscall_cancel.S b/sysdeps/unix/sysv/linux/x86_64/syscall_cancel.S
new file mode 100644
index 0000000..35d4733
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/x86_64/syscall_cancel.S
@@ -0,0 +1,59 @@
+/* Cancellable syscall wrapper - x86_64 version.
+ Copyright (C) 2019 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#include <sysdep.h>
+
+/* long int [rax] __syscall_cancel_arch (volatile int *cancelhandling [%rdi],
+ __syscall_arg_t nr [%rsi],
+ __syscall_arg_t arg1 [%rdx],
+ __syscall_arg_t arg2 [%rcx],
+ __syscall_arg_t arg3 [%r8],
+ __syscall_arg_t arg4 [%r9],
+ __syscall_arg_t arg5 [SP+8],
+ __syscall_arg_t arg6 [SP+16]) */
+
+ENTRY (__syscall_cancel_arch)
+
+ .globl __syscall_cancel_arch_start
+__syscall_cancel_arch_start:
+
+ /* if (*cancelhandling & CANCELED_BITMASK)
+ __syscall_do_cancel() */
+ mov (%rdi),%eax
+ testb $TCB_CANCELED_BITMASK, (%rdi)
+ jne __syscall_do_cancel
+
+ /* Issue a 6 argument syscall, the nr [%rax] being the syscall
+ number. */
+ mov %rdi,%r11
+ mov %rsi,%rax
+ mov %rdx,%rdi
+ mov %rcx,%rsi
+ mov %r8,%rdx
+ mov %r9,%r10
+ mov 8(%rsp),%r8
+ mov 16(%rsp),%r9
+ mov %r11,8(%rsp)
+ syscall
+
+ .globl __syscall_cancel_arch_end
+__syscall_cancel_arch_end:
+ ret
+
+END (__syscall_cancel_arch)
+libc_hidden_def (__syscall_cancel_arch)
diff --git a/sysdeps/x86_64/nptl/tcb-offsets.sym b/sysdeps/x86_64/nptl/tcb-offsets.sym
index ae80347..699f6fa 100644
--- a/sysdeps/x86_64/nptl/tcb-offsets.sym
+++ b/sysdeps/x86_64/nptl/tcb-offsets.sym
@@ -15,12 +15,5 @@ VGETCPU_CACHE_OFFSET offsetof (tcbhead_t, vgetcpu_cache)
FEATURE_1_OFFSET offsetof (tcbhead_t, feature_1)
SSP_BASE_OFFSET offsetof (tcbhead_t, ssp_base)
--- Not strictly offsets, but these values are also used in the TCB.
-TCB_CANCELSTATE_BITMASK CANCELSTATE_BITMASK
-TCB_CANCELTYPE_BITMASK CANCELTYPE_BITMASK
-TCB_CANCELING_BITMASK CANCELING_BITMASK
-TCB_CANCELED_BITMASK CANCELED_BITMASK
-TCB_EXITING_BITMASK EXITING_BITMASK
-TCB_CANCEL_RESTMASK CANCEL_RESTMASK
-TCB_TERMINATED_BITMASK TERMINATED_BITMASK
-TCB_PTHREAD_CANCELED PTHREAD_CANCELED
+-- Not strictly offsets, used on syscall_cancel.S
+TCB_CANCELED_BITMASK CANCELED_BITMASK
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2020-04-07 14:03 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
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2019-08-19 20:35 [glibc/azanella/bz12683] nptl: x86_64: Fix Race conditions in pthread cancellation (BZ#12683) Adhemerval Zanella
2019-10-17 13:57 Adhemerval Zanella
2020-04-03 20:23 [glibc/azanella/bz12683] nptl: x86_64: Fix Race conditions in pthread cancellation [BZ#12683] Adhemerval Zanella
2020-04-07 14:03 Adhemerval Zanella
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