1 files changed, 165 insertions, 0 deletions
diff --git a/main/musl/0004-properly-access-mcontext_t-program-counter-in-cancel.patch b/main/musl/0004-properly-access-mcontext_t-program-counter-in-cancel.patch
new file mode 100644
index 0000000000..d699892c08
--- /dev/null
+++ b/main/musl/0004-properly-access-mcontext_t-program-counter-in-cancel.patch
@@ -0,0 +1,165 @@
+From cb1bf2f321b45a06447133b3db00621b7300c456 Mon Sep 17 00:00:00 2001
+From: Rich Felker <dalias@aerifal.cx>
+Date: Mon, 2 Nov 2015 12:39:28 -0500
+Subject: [PATCH] properly access mcontext_t program counter in cancellation
+ handler
+
+using the actual mcontext_t definition rather than an overlaid pointer
+array both improves correctness/readability and eliminates some ugly
+hacks for archs with 64-bit registers bit 32-bit program counter.
+
+also fix UB due to comparison of pointers not in a common array
+object.
+---
+ arch/aarch64/pthread_arch.h    | 2 +-
+ arch/arm/pthread_arch.h        | 2 +-
+ arch/i386/pthread_arch.h       | 2 +-
+ arch/microblaze/pthread_arch.h | 2 +-
+ arch/mips/pthread_arch.h       | 2 +-
+ arch/or1k/pthread_arch.h       | 3 +--
+ arch/powerpc/pthread_arch.h    | 3 +--
+ arch/sh/pthread_arch.h         | 2 +-
+ arch/x32/pthread_arch.h        | 2 +-
+ arch/x86_64/pthread_arch.h     | 2 +-
+ src/thread/pthread_cancel.c    | 7 ++++---
+ 11 files changed, 14 insertions(+), 15 deletions(-)
+
+diff --git a/arch/aarch64/pthread_arch.h b/arch/aarch64/pthread_arch.h
+index 74276f4..b2e2d8f 100644
+--- a/arch/aarch64/pthread_arch.h
++++ b/arch/aarch64/pthread_arch.h
+@@ -8,4 +8,4 @@ static inline struct pthread *__pthread_self()
+ #define TLS_ABOVE_TP
+ #define TP_ADJ(p) ((char *)(p) + sizeof(struct pthread) - 16)
+ 
+-#define CANCEL_REG_IP 33
++#define MC_PC pc
+diff --git a/arch/arm/pthread_arch.h b/arch/arm/pthread_arch.h
+index 4a4dd09..8b8a7fb 100644
+--- a/arch/arm/pthread_arch.h
++++ b/arch/arm/pthread_arch.h
+@@ -27,4 +27,4 @@ static inline pthread_t __pthread_self()
+ #define TLS_ABOVE_TP
+ #define TP_ADJ(p) ((char *)(p) + sizeof(struct pthread) - 8)
+ 
+-#define CANCEL_REG_IP 18
++#define MC_PC arm_pc
+diff --git a/arch/i386/pthread_arch.h b/arch/i386/pthread_arch.h
+index 1c06c76..7f38a56 100644
+--- a/arch/i386/pthread_arch.h
++++ b/arch/i386/pthread_arch.h
+@@ -7,4 +7,4 @@ static inline struct pthread *__pthread_self()
+ 
+ #define TP_ADJ(p) (p)
+ 
+-#define CANCEL_REG_IP 14
++#define MC_PC gregs[REG_EIP]
+diff --git a/arch/microblaze/pthread_arch.h b/arch/microblaze/pthread_arch.h
+index 259d3d6..08d1ba7 100644
+--- a/arch/microblaze/pthread_arch.h
++++ b/arch/microblaze/pthread_arch.h
+@@ -7,4 +7,4 @@ static inline struct pthread *__pthread_self()
+ 
+ #define TP_ADJ(p) (p)
+ 
+-#define CANCEL_REG_IP 32
++#define MC_PC regs.pc
+diff --git a/arch/mips/pthread_arch.h b/arch/mips/pthread_arch.h
+index 93edbd4..8a49965 100644
+--- a/arch/mips/pthread_arch.h
++++ b/arch/mips/pthread_arch.h
+@@ -16,4 +16,4 @@ static inline struct pthread *__pthread_self()
+ 
+ #define DTP_OFFSET 0x8000
+ 
+-#define CANCEL_REG_IP (3-(union {int __i; char __b;}){1}.__b)
++#define MC_PC pc
+diff --git a/arch/or1k/pthread_arch.h b/arch/or1k/pthread_arch.h
+index ad63169..7decd76 100644
+--- a/arch/or1k/pthread_arch.h
++++ b/arch/or1k/pthread_arch.h
+@@ -14,5 +14,4 @@ static inline struct pthread *__pthread_self()
+ #define TLS_ABOVE_TP
+ #define TP_ADJ(p) ((char *)(p) + sizeof(struct pthread))
+ 
+-/* word-offset to 'pc' in mcontext_t */
+-#define CANCEL_REG_IP 32
++#define MC_PC regs.pc
+diff --git a/arch/powerpc/pthread_arch.h b/arch/powerpc/pthread_arch.h
+index bb7405d..7c5c4fa 100644
+--- a/arch/powerpc/pthread_arch.h
++++ b/arch/powerpc/pthread_arch.h
+@@ -15,9 +15,8 @@ static inline struct pthread *__pthread_self()
+ 
+ #define DTP_OFFSET 0x8000
+ 
+-// offset of the PC register in mcontext_t, divided by the system wordsize
+ // the kernel calls the ip "nip", it's the first saved value after the 32
+ // GPRs.
+-#define CANCEL_REG_IP 32
++#define MC_PC gregs[32]
+ 
+ #define CANARY canary_at_end
+diff --git a/arch/sh/pthread_arch.h b/arch/sh/pthread_arch.h
+index 65c389f..2756e7e 100644
+--- a/arch/sh/pthread_arch.h
++++ b/arch/sh/pthread_arch.h
+@@ -8,4 +8,4 @@ static inline struct pthread *__pthread_self()
+ #define TLS_ABOVE_TP
+ #define TP_ADJ(p) ((char *)(p) + sizeof(struct pthread) - 8)
+ 
+-#define CANCEL_REG_IP 17
++#define MC_PC sc_pc
+diff --git a/arch/x32/pthread_arch.h b/arch/x32/pthread_arch.h
+index 033bfd6..ecb0bbf 100644
+--- a/arch/x32/pthread_arch.h
++++ b/arch/x32/pthread_arch.h
+@@ -7,6 +7,6 @@ static inline struct pthread *__pthread_self()
+ 
+ #define TP_ADJ(p) (p)
+ 
+-#define CANCEL_REG_IP 32
++#define MC_PC gregs[REG_RIP]
+ 
+ #define CANARY canary2
+diff --git a/arch/x86_64/pthread_arch.h b/arch/x86_64/pthread_arch.h
+index 29e4590..c61509c 100644
+--- a/arch/x86_64/pthread_arch.h
++++ b/arch/x86_64/pthread_arch.h
+@@ -7,4 +7,4 @@ static inline struct pthread *__pthread_self()
+ 
+ #define TP_ADJ(p) (p)
+ 
+-#define CANCEL_REG_IP 16
++#define MC_PC gregs[REG_RIP]
+diff --git a/src/thread/pthread_cancel.c b/src/thread/pthread_cancel.c
+index 0151a1a..6eaf72c 100644
+--- a/src/thread/pthread_cancel.c
++++ b/src/thread/pthread_cancel.c
+@@ -1,3 +1,4 @@
++#define _GNU_SOURCE
+ #include <string.h>
+ #include "pthread_impl.h"
+ #include "syscall.h"
+@@ -61,15 +62,15 @@ static void cancel_handler(int sig, siginfo_t *si, void *ctx)
+ {
+ 	pthread_t self = __pthread_self();
+ 	ucontext_t *uc = ctx;
+-	const char *ip = ((char **)&uc->uc_mcontext)[CANCEL_REG_IP];
++	uintptr_t pc = uc->uc_mcontext.MC_PC;
+ 
+ 	a_barrier();
+ 	if (!self->cancel || self->canceldisable == PTHREAD_CANCEL_DISABLE) return;
+ 
+ 	_sigaddset(&uc->uc_sigmask, SIGCANCEL);
+ 
+-	if (self->cancelasync || ip >= __cp_begin && ip < __cp_end) {
+-		((char **)&uc->uc_mcontext)[CANCEL_REG_IP] = (char *)__cp_cancel;
++	if (self->cancelasync || pc >= (uintptr_t)__cp_begin && pc < (uintptr_t)__cp_end) {
++		uc->uc_mcontext.MC_PC = (uintptr_t)__cp_cancel;
+ 		return;
+ 	}
+ 
+-- 
+2.7.0
+