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| author | Sergey Bugaev <bugaevc@gmail.com> | 2024-01-03 20:14:40 +0300 |
|---|---|---|
| committer | Samuel Thibault <samuel.thibault@ens-lyon.org> | 2024-01-04 23:47:03 +0100 |
| commit | 24b707c1665afae7eb302542ffa92d53aa577111 (patch) | |
| tree | 04f19e3654af1112eafd57f2f838097d1c6c147d /sysdeps/mach | |
| parent | 35694d3416b273ac19d67ffa49b7969f36684ae1 (diff) | |
| download | glibc-24b707c1665afae7eb302542ffa92d53aa577111.tar.gz glibc-24b707c1665afae7eb302542ffa92d53aa577111.tar.xz glibc-24b707c1665afae7eb302542ffa92d53aa577111.zip | |
hurd: Pass the data pointer to _hurd_stack_setup explicitly
Instead of relying on the stack frame layout to figure out where the stack pointer was prior to the _hurd_stack_setup () call, just pass the pointer as an argument explicitly. This is less brittle and much more portable. Signed-off-by: Sergey Bugaev <bugaevc@gmail.com> Message-ID: <20240103171502.1358371-8-bugaevc@gmail.com>
Diffstat (limited to 'sysdeps/mach')
| -rw-r--r-- | sysdeps/mach/hurd/i386/static-start.S | 3 | ||||
| -rw-r--r-- | sysdeps/mach/hurd/x86/init-first.c | 16 | ||||
| -rw-r--r-- | sysdeps/mach/hurd/x86_64/static-start.S | 1 |
3 files changed, 11 insertions, 9 deletions
diff --git a/sysdeps/mach/hurd/i386/static-start.S b/sysdeps/mach/hurd/i386/static-start.S index d83505b2bc..3ffcb47d90 100644 --- a/sysdeps/mach/hurd/i386/static-start.S +++ b/sysdeps/mach/hurd/i386/static-start.S @@ -19,7 +19,10 @@ .text .globl _start _start: + pushl %esp call _hurd_stack_setup + /* No need to "addl %4, %esp", since _hurd_stack_setup + * returns with an already adjusted stack pointer. */ xorl %edx, %edx jmp _start1 diff --git a/sysdeps/mach/hurd/x86/init-first.c b/sysdeps/mach/hurd/x86/init-first.c index bb05141899..6f71d71bf0 100644 --- a/sysdeps/mach/hurd/x86/init-first.c +++ b/sysdeps/mach/hurd/x86/init-first.c @@ -197,7 +197,7 @@ strong_alias (posixland_init, __libc_init_first); which should not exist at all. */ void inhibit_stack_protector -_hurd_stack_setup (void) +_hurd_stack_setup (void **argptr) { /* This is the very first C code that runs in a statically linked executable -- calling this function is the first thing that _start in @@ -206,14 +206,12 @@ _hurd_stack_setup (void) _start1 expects the arguments, environment, and a Hurd data block to be located at the top of the stack. The data may already be located there, - or we may need to receive it from the exec server. */ - void *caller = __builtin_extract_return_addr (__builtin_return_address (0)); - /* If the arguments and environment are already located on the stack, this is - where they are, just above our call frame. Note that this may not be a - valid pointer in case we're supposed to receive the arguments from the exec - server, so we can not dereference it yet. */ - void **p = (void **) __builtin_frame_address (0) + 2; + or we may need to receive it from the exec server. If the data is located + on the stack (just above our call frame), argptr points to it. Note that + this may not be a valid pointer in case we're supposed to receive the + arguments from the exec server, so we can not dereference it yet. */ + void *caller = __builtin_extract_return_addr (__builtin_return_address (0)); /* Init the essential things. */ first_init (); @@ -245,7 +243,7 @@ _hurd_stack_setup (void) the stack pointer to the data (which is somewhere on the current stack anyway). This way, _start1 find the data on the top of the stack, just as it expects to. */ - _hurd_startup (p, &doinit); + _hurd_startup (argptr, &doinit); __builtin_unreachable (); } #endif diff --git a/sysdeps/mach/hurd/x86_64/static-start.S b/sysdeps/mach/hurd/x86_64/static-start.S index 9b9db937bd..0ec00905a0 100644 --- a/sysdeps/mach/hurd/x86_64/static-start.S +++ b/sysdeps/mach/hurd/x86_64/static-start.S @@ -25,6 +25,7 @@ _start: leaq __strlen_sse2(%rip), %rax movq %rax, strlen@GOTPCREL(%rip) + movq %rsp, %rdi call _hurd_stack_setup xorq %rdx, %rdx jmp _start1 |