The patch titled
Subject: signal: factor copy_siginfo_to_external32 from copy_siginfo_to_user32
has been added to the -mm tree. Its filename is
signal-factor-copy_siginfo_to_external32-from-copy_siginfo_to_user32.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/signal-factor-copy_siginfo_to_external32-from-copy_siginfo_to_user32.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/signal-factor-copy_siginfo_to_external32-from-copy_siginfo_to_user32.patch
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------------------------------------------------------
From: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>
Subject: signal: factor copy_siginfo_to_external32 from copy_siginfo_to_user32
To remove the use of set_fs in the coredump code there needs to be a way
to convert a kernel siginfo to a userspace compat siginfo.
Call that function copy_siginfo_to_compat and factor it out of
copy_siginfo_to_user32.
The existence of x32 complicates this code. On x32 SIGCHLD uses 64bit
times for utime and stime. As only SIGCHLD is affected and SIGCHLD never
causes a coredump I have avoided handling that case.
Link: http://lkml.kernel.org/r/20200421154204.252921-3-hch@xxxxxx
Signed-off-by: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Cc: Jeremy Kerr <jk@xxxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/compat.h | 2
kernel/signal.c | 109 ++++++++++++++++++++++-----------------
2 files changed, 64 insertions(+), 47 deletions(-)
--- a/include/linux/compat.h~signal-factor-copy_siginfo_to_external32-from-copy_siginfo_to_user32
+++ a/include/linux/compat.h
@@ -402,6 +402,8 @@ long compat_get_bitmap(unsigned long *ma
unsigned long bitmap_size);
long compat_put_bitmap(compat_ulong_t __user *umask, unsigned long *mask,
unsigned long bitmap_size);
+void copy_siginfo_to_external32(struct compat_siginfo *to,
+ const struct kernel_siginfo *from);
int copy_siginfo_from_user32(kernel_siginfo_t *to, const struct compat_siginfo __user *from);
int copy_siginfo_to_user32(struct compat_siginfo __user *to, const kernel_siginfo_t *from);
int get_compat_sigevent(struct sigevent *event,
--- a/kernel/signal.c~signal-factor-copy_siginfo_to_external32-from-copy_siginfo_to_user32
+++ a/kernel/signal.c
@@ -3231,94 +3231,109 @@ int copy_siginfo_from_user(kernel_siginf
}
#ifdef CONFIG_COMPAT
-int copy_siginfo_to_user32(struct compat_siginfo __user *to,
- const struct kernel_siginfo *from)
-#if defined(CONFIG_X86_X32_ABI) || defined(CONFIG_IA32_EMULATION)
-{
- return __copy_siginfo_to_user32(to, from, in_x32_syscall());
-}
-int __copy_siginfo_to_user32(struct compat_siginfo __user *to,
- const struct kernel_siginfo *from, bool x32_ABI)
-#endif
+void copy_siginfo_to_external32(struct compat_siginfo *to,
+ const struct kernel_siginfo *from)
{
- struct compat_siginfo new;
- memset(&new, 0, sizeof(new));
+ /*
+ * This function does not work properly for SIGCHLD on x32,
+ * but it does not need to as SIGCHLD never causes a coredump.
+ */
+ memset(to, 0, sizeof(*to));
- new.si_signo = from->si_signo;
- new.si_errno = from->si_errno;
- new.si_code = from->si_code;
+ to->si_signo = from->si_signo;
+ to->si_errno = from->si_errno;
+ to->si_code = from->si_code;
switch(siginfo_layout(from->si_signo, from->si_code)) {
case SIL_KILL:
- new.si_pid = from->si_pid;
- new.si_uid = from->si_uid;
+ to->si_pid = from->si_pid;
+ to->si_uid = from->si_uid;
break;
case SIL_TIMER:
- new.si_tid = from->si_tid;
- new.si_overrun = from->si_overrun;
- new.si_int = from->si_int;
+ to->si_tid = from->si_tid;
+ to->si_overrun = from->si_overrun;
+ to->si_int = from->si_int;
break;
case SIL_POLL:
- new.si_band = from->si_band;
- new.si_fd = from->si_fd;
+ to->si_band = from->si_band;
+ to->si_fd = from->si_fd;
break;
case SIL_FAULT:
- new.si_addr = ptr_to_compat(from->si_addr);
+ to->si_addr = ptr_to_compat(from->si_addr);
#ifdef __ARCH_SI_TRAPNO
- new.si_trapno = from->si_trapno;
+ to->si_trapno = from->si_trapno;
#endif
break;
case SIL_FAULT_MCEERR:
- new.si_addr = ptr_to_compat(from->si_addr);
+ to->si_addr = ptr_to_compat(from->si_addr);
#ifdef __ARCH_SI_TRAPNO
- new.si_trapno = from->si_trapno;
+ to->si_trapno = from->si_trapno;
#endif
- new.si_addr_lsb = from->si_addr_lsb;
+ to->si_addr_lsb = from->si_addr_lsb;
break;
case SIL_FAULT_BNDERR:
- new.si_addr = ptr_to_compat(from->si_addr);
+ to->si_addr = ptr_to_compat(from->si_addr);
#ifdef __ARCH_SI_TRAPNO
- new.si_trapno = from->si_trapno;
+ to->si_trapno = from->si_trapno;
#endif
- new.si_lower = ptr_to_compat(from->si_lower);
- new.si_upper = ptr_to_compat(from->si_upper);
+ to->si_lower = ptr_to_compat(from->si_lower);
+ to->si_upper = ptr_to_compat(from->si_upper);
break;
case SIL_FAULT_PKUERR:
- new.si_addr = ptr_to_compat(from->si_addr);
+ to->si_addr = ptr_to_compat(from->si_addr);
#ifdef __ARCH_SI_TRAPNO
- new.si_trapno = from->si_trapno;
+ to->si_trapno = from->si_trapno;
#endif
- new.si_pkey = from->si_pkey;
+ to->si_pkey = from->si_pkey;
break;
case SIL_CHLD:
- new.si_pid = from->si_pid;
- new.si_uid = from->si_uid;
- new.si_status = from->si_status;
+ to->si_pid = from->si_pid;
+ to->si_uid = from->si_uid;
+ to->si_status = from->si_status;
+ to->si_utime = from->si_utime;
+ to->si_stime = from->si_stime;
#ifdef CONFIG_X86_X32_ABI
if (x32_ABI) {
- new._sifields._sigchld_x32._utime = from->si_utime;
- new._sifields._sigchld_x32._stime = from->si_stime;
+ to->_sifields._sigchld_x32._utime = from->si_utime;
+ to->_sifields._sigchld_x32._stime = from->si_stime;
} else
#endif
{
- new.si_utime = from->si_utime;
- new.si_stime = from->si_stime;
}
break;
case SIL_RT:
- new.si_pid = from->si_pid;
- new.si_uid = from->si_uid;
- new.si_int = from->si_int;
+ to->si_pid = from->si_pid;
+ to->si_uid = from->si_uid;
+ to->si_int = from->si_int;
break;
case SIL_SYS:
- new.si_call_addr = ptr_to_compat(from->si_call_addr);
- new.si_syscall = from->si_syscall;
- new.si_arch = from->si_arch;
+ to->si_call_addr = ptr_to_compat(from->si_call_addr);
+ to->si_syscall = from->si_syscall;
+ to->si_arch = from->si_arch;
break;
}
+}
+int copy_siginfo_to_user32(struct compat_siginfo __user *to,
+ const struct kernel_siginfo *from)
+#if defined(CONFIG_X86_X32_ABI) || defined(CONFIG_IA32_EMULATION)
+{
+ return __copy_siginfo_to_user32(to, from, in_x32_syscall());
+}
+int __copy_siginfo_to_user32(struct compat_siginfo __user *to,
+ const struct kernel_siginfo *from, bool x32_ABI)
+#endif
+{
+ struct compat_siginfo new;
+
+ copy_siginfo_to_external32(&new, from);
+#ifdef CONFIG_X86_X32_ABI
+ if (x32_ABI && from->si_signo == SIGCHLD) {
+ new._sifields._sigchld_x32._utime = from->si_utime;
+ new._sifields._sigchld_x32._stime = from->si_stime;
+ }
+#endif
if (copy_to_user(to, &new, sizeof(struct compat_siginfo)))
return -EFAULT;
-
return 0;
}
_
Patches currently in -mm which might be from ebiederm@xxxxxxxxxxxx are
signal-factor-copy_siginfo_to_external32-from-copy_siginfo_to_user32.patch
binfmt_elf-femove-the-set_fs-in-fill_siginfo_note.patch
