Re: CVS commit: src/libexec/ld.elf_so

[Ryo ONODERA <ryo%tetera.org@localhost>]

Hi,

This commit fixes my problems.
And I found one more problem.

xsltproc command from pkgsrc/textproc/libxslt gets segfault as follows:
This blocks a build of pkgsrc/databases/tdb.

$ xsltproc --nonet /usr/pkg/share/xsl/docbook/manpages/docbook.xsl              zsh: segmentation fault (core dumped)  xsltproc --nonet /usr/pkg/share/xsl/docbook/manpages/docbook.xsl
$ gdb /usr/pkg/bin/xsltproc ./xsltproc.core                                     GNU gdb (GDB) 17.1
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Reading symbols from /usr/pkg/bin/xsltproc...
(No debugging symbols found in /usr/pkg/bin/xsltproc)
[New process 15295]
Core was generated by `xsltproc'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0  _rtld_load_library (
    name=name@entry=0x7f7fff0cc400 "/usr/pkg/lib/libxslt-plugins/freshmeat_net_projects_freshmeat_submit.so", refobj=refobj@entry=0x7ece9b002000,
--Type <RET> for more, q to quit, c to continue without paging--
    flags=flags@entry=8, mask=mask@entry=0x7f7fff0cc3a0)
    at /usr/src/libexec/ld.elf_so/search.c:197
197             assert(obj->refcount > 0);
(gdb) bt
#0  _rtld_load_library (
    name=name@entry=0x7f7fff0cc400 "/usr/pkg/lib/libxslt-plugins/freshmeat_net_projects_freshmeat_submit.so", refobj=refobj@entry=0x7ece9b002000,
    flags=flags@entry=8, mask=mask@entry=0x7f7fff0cc3a0)
    at /usr/src/libexec/ld.elf_so/search.c:197
#1  0x00007f7ff7a1fc4e in dlopen (
    name=0x7f7fff0cc400 "/usr/pkg/lib/libxslt-plugins/freshmeat_net_projects_freshmeat_submit.so", mode=514) at /usr/src/libexec/ld.elf_so/rtld.c:1697
#2  0x00007ece9afc86ec in xsltExtModuleRegisterDynamic ()
   from /usr/pkg/lib/libxslt.so.1
#3  0x00007ece9afc9f3c in xsltExtModuleTopLevelLookup ()
   from /usr/pkg/lib/libxslt.so.1
#4  0x00007ece9afb812a in xsltParseStylesheetProcess ()
   from /usr/pkg/lib/libxslt.so.1
#5  0x00007ece9afcd0db in xsltParseStylesheetInclude ()
   from /usr/pkg/lib/libxslt.so.1
#6  0x00007ece9afb80eb in xsltParseStylesheetProcess ()
   from /usr/pkg/lib/libxslt.so.1
#7  0x00007ece9afb9156 in xsltParseStylesheetUser ()
   from /usr/pkg/lib/libxslt.so.1
#8  0x00007ece9afb9248 in xsltParseStylesheetImportedDoc ()
   from /usr/pkg/lib/libxslt.so.1
#9  0x00007ece9afccf08 in xsltParseStylesheetImport ()
--Type <RET> for more, q to quit, c to continue without paging--qq
❌️ Quit
(gdb) q

search.c line 197 is a assert() of the following snippet.

   192  found:
   193          obj = _rtld_load_object(pathname, flags, mask);
   194          if (obj == OBJ_ERR)
   195                  return NULL;
   196
   197          assert(obj->refcount > 0);
   198          return obj;
   199  }

xsltproc apparently try to open non existent file,
/usr/pkg/lib/libxslt-plugins/freshmeat_net_projects_freshmeat_submit.so .
However it is detected as "found".

Thank you.

"Taylor R Campbell" <riastradh%netbsd.org@localhost> writes:

> Module Name:	src
> Committed By:	riastradh
> Date:		Mon Jul 20 18:46:37 UTC 2026
>
> Modified Files:
> 	src/libexec/ld.elf_so: tls.c xmalloc.c
>
> Log Message:
> ld.elf_so: Fix static TLS alignment on variant II platforms.
>
> Only affects obscure architectures like x86, though.
>
> Sprinkle assertions to make sure this breaks in other ways on other
> architectures too, like variant I, or variant II with _lwp_gettcb().
> Fair's fair, right?
>
> XXX We should consider verifying that every Elf_Phdr::p_align is
> reasonable (i.e., is a power of two, or is zero but only if p_memsz
> is also zero), and that p_filesz <= p_memsz, in headers.c for the
> main object and in map_object.c for other objects.
>
> PR bin/60469: bin/60469: assertion "ALIGNED_P(q, obj->tlsalign)"
> failed: file "/usr/src/libexec/ld.elf_so/tls.c", line 333
>
>
> To generate a diff of this commit:
> cvs rdiff -u -r1.29 -r1.30 src/libexec/ld.elf_so/tls.c
> cvs rdiff -u -r1.27 -r1.28 src/libexec/ld.elf_so/xmalloc.c
>
> Please note that diffs are not public domain; they are subject to the
> copyright notices on the relevant files.
>
> Modified files:
>
> Index: src/libexec/ld.elf_so/tls.c
> diff -u src/libexec/ld.elf_so/tls.c:1.29 src/libexec/ld.elf_so/tls.c:1.30
> --- src/libexec/ld.elf_so/tls.c:1.29	Sun Mar 15 13:56:17 2026
> +++ src/libexec/ld.elf_so/tls.c	Mon Jul 20 18:46:37 2026
> @@ -1,4 +1,4 @@
> -/*	$NetBSD: tls.c,v 1.29 2026/03/15 13:56:17 skrll Exp $	*/
> +/*	$NetBSD: tls.c,v 1.30 2026/07/20 18:46:37 riastradh Exp $	*/
>  /*-
>   * Copyright (c) 2011 The NetBSD Foundation, Inc.
>   * All rights reserved.
> @@ -29,7 +29,7 @@
>   */
>  
>  #include <sys/cdefs.h>
> -__RCSID("$NetBSD: tls.c,v 1.29 2026/03/15 13:56:17 skrll Exp $");
> +__RCSID("$NetBSD: tls.c,v 1.30 2026/07/20 18:46:37 riastradh Exp $");
>  
>  /*
>   * Thread-local storage
> @@ -109,7 +109,8 @@ static void *_rtld_tls_module_allocate(s
>  static size_t _rtld_tls_static_space;	/* Static TLS space allocated */
>  static size_t _rtld_tls_static_offset =
>  	_RTLD_TLS_INITIAL_OFFSET;	/* Next offset for static TLS to use */
> -static size_t _rtld_tls_static_max_align;
> +static size_t _rtld_tls_static_max_align =
> +    MAX(alignof(max_align_t), alignof(struct tls_tcb));
>  
>  size_t _rtld_tls_dtv_generation = 1;	/* Bumped on each load of obj w/ TLS */
>  size_t _rtld_tls_max_index = 1;		/* Max index into up-to-date DTV */
> @@ -249,15 +250,20 @@ _rtld_tls_initial_allocation(void)
>  
>  #ifndef __HAVE_TLS_VARIANT_I
>  	_rtld_tls_static_space = roundup2(_rtld_tls_static_space,
> -	    alignof(max_align_t));
> +	    _rtld_tls_static_max_align);
>  
>  #ifdef __HAVE___LWP_SETTCB
>  	if (_rtld_tls_static_max_align > sizeof(struct tls_tcb))
>  		_rtld_tls_static_space +=
>  		     _rtld_tls_static_max_align - sizeof(struct tls_tcb);
> +	assert(_rtld_tls_static_space % _rtld_tls_static_max_align ==
> +	    sizeof(struct tls_tcb) % _rtld_tls_static_max_align);
> +#else
> +	assert(ALIGNED_P(_rtld_tls_static_space, _rtld_tls_static_max_align));
>  #endif
>  
>  #endif
> +
>  	dbg(("_rtld_tls_static_space %zu", _rtld_tls_static_space));
>  
>  	tcb = _rtld_tls_allocate_locked();
> @@ -288,9 +294,20 @@ _rtld_tls_allocate_locked(void)
>  	Obj_Entry *obj;
>  	struct tls_tcb *tcb;
>  	uint8_t *p, *q;
> +	uint8_t *lo __diagused, *hi __diagused; /* bounds of TLS space */
> +
> +#ifdef __HAVE_TLS_VARIANT_II
> +#ifdef __HAVE___LWP_SETTCB
> +	assert(_rtld_tls_static_space % _rtld_tls_static_max_align ==
> +	    sizeof(struct tls_tcb) % _rtld_tls_static_max_align);
> +#else
> +	assert(ALIGNED_P(_rtld_tls_static_space, _rtld_tls_static_max_align));
> +#endif
> +#endif
>  
>  	p = xmalloc_aligned(_rtld_tls_static_space + sizeof(struct tls_tcb),
>  	    _rtld_tls_static_max_align, 0);
> +	assert(ALIGNED_P(p, _rtld_tls_static_max_align));
>  
>  	memset(p, 0, _rtld_tls_static_space + sizeof(struct tls_tcb));
>  #ifdef __HAVE_TLS_VARIANT_I
> @@ -298,14 +315,22 @@ _rtld_tls_allocate_locked(void)
>  	if (_rtld_tls_static_max_align > sizeof(struct tls_tcb))
>  		p += _rtld_tls_static_max_align - sizeof(struct tls_tcb);
>  #endif
> +	assert(ALIGNED_P(p, alignof(struct tls_tcb)));
>  	tcb = (struct tls_tcb *)p;
>  	p += sizeof(struct tls_tcb);
> +	assert(ALIGNED_P(p, _rtld_tls_static_max_align));
> +	lo = p;
>  #else
> +	lo = p;
>  	p += _rtld_tls_static_space;
> +	assert(ALIGNED_P(p, _rtld_tls_static_max_align));
> +	assert(ALIGNED_P(p, alignof(struct tls_tcb)));
>  	tcb = (struct tls_tcb *)p;
>  	tcb->tcb_self = tcb;
>  #endif
> -	dbg(("lwp %d tls tcb %p", _lwp_self(), tcb));
> +	hi = lo + _rtld_tls_static_space;
> +	dbg(("lwp %d tls tcb %p p %p", _lwp_self(), tcb, p));
> +	dbg(("tls range [%p,%p)", lo, hi));
>  	/*
>  	 * "2 +" because the first element is the generation and the second
>  	 * one is the maximum index.
> @@ -317,20 +342,37 @@ _rtld_tls_allocate_locked(void)
>  
>  	for (obj = _rtld_objlist; obj != NULL; obj = obj->next) {
>  		if (obj->tls_static) {
> +			dbg(("%s: [lwp %d] tls offset=0x%zx size=0x%zx"
> +				" initsize=0x%zx align=0x%zx",
> +				obj->path, _lwp_self(),
> +				obj->tlsoffset, obj->tlssize,
> +				obj->tlsinitsize, obj->tlsalign));
> +			assert(obj->tlsinitsize <= obj->tlssize);
> +			assert(obj->tlsoffset <= _rtld_tls_static_space);
> +			assert(obj->tlssize <= _rtld_tls_static_space);
>  #ifdef __HAVE_TLS_VARIANT_I
> +			assert(obj->tlsoffset <= _rtld_tls_static_space -
> +			    obj->tlssize);
>  			q = p + obj->tlsoffset;
>  #else
> +			assert(obj->tlssize <= obj->tlsoffset);
>  			q = p - obj->tlsoffset;
>  #endif
>  			dbg(("%s: [lwp %d] tls dtv %p-%p index %zu "
> -			    "offset %zx alignment %zx tlsinit %p%s",
> +			    "offset 0x%zx alignment 0x%zx tlsinit %p%s",
>  			    obj->path, _lwp_self(),
>  			    q, q + obj->tlsinitsize, obj->tlsindex,
>  			    obj->tlsoffset, obj->tlsalign, obj->tlsinit,
> -			    ALIGNED_P(q, obj->tlsalign) ? "" :
> -				 " BAD ALIGNMENT"));
> +			    (obj->tlssize == 0 || ALIGNED_P(q, obj->tlsalign))
> +				? "" : " BAD ALIGNMENT"));
>  
> -			assert(ALIGNED_P(q, obj->tlsalign));
> +			assert(lo <= q);
> +			assert(q + obj->tlssize <= hi);
> +			assert(obj->tlssize == 0 || obj->tlsalign != 0);
> +			assert(obj->tlssize == 0 ||
> +			    (obj->tlsalign & (obj->tlsalign - 1)) == 0);
> +			assert(obj->tlssize == 0 ||
> +			    ALIGNED_P(q, obj->tlsalign));
>  
>  			if (obj->tlsinitsize)
>  				memcpy(q, obj->tlsinit, obj->tlsinitsize);
> @@ -436,6 +478,11 @@ _rtld_tls_module_allocate(struct tls_tcb
>  		return p;
>  	}
>  
> +	assert(obj->tlsinitsize <= obj->tlssize);
> +	assert(obj->tlssize == 0 || obj->tlsalign != 0);
> +	assert(obj->tlssize == 0 ||
> +	    (obj->tlsalign & (obj->tlsalign - 1)) == 0);
> +
>  	p = xmalloc_aligned(obj->tlssize, obj->tlsalign, 0);
>  	memcpy(p, obj->tlsinit, obj->tlsinitsize);
>  	memset(p + obj->tlsinitsize, 0, obj->tlssize - obj->tlsinitsize);
> @@ -460,12 +507,28 @@ _rtld_tls_offset_allocate(Obj_Entry *obj
>  {
>  	size_t offset, next_offset;
>  
> +	/*
> +	 * If this object uses dynamic TLS only, the caller shouldn't
> +	 * be trying to allocate a static TLS offset.
> +	 */
>  	if (obj->tls_dynamic)
>  		return -1;
>  
> +	/*
> +	 * If we have already allocated a static TLS offset, nothing
> +	 * more to do.
> +	 */
>  	if (obj->tls_static)
>  		return 0;
>  
> +	/*
> +	 * If the TLS size is zero, not much to do here -- choose zero
> +	 * offset (always valid) and mark the object as having
> +	 * allocated a static TLS offset.
> +	 *
> +	 * XXX Is it a problem for multiple objects to have the same
> +	 * TLS offset?
> +	 */
>  	if (obj->tlssize == 0) {
>  		obj->tlsoffset = 0;
>  		obj->tls_static = 1;
> @@ -483,6 +546,7 @@ _rtld_tls_offset_allocate(Obj_Entry *obj
>  	    obj->tlsalign);
>  	next_offset = offset;
>  #endif
> +	assert(ALIGNED_P(offset, obj->tlsalign));
>  
>  	/*
>  	 * Check if the static allocation was already done.
> @@ -509,6 +573,13 @@ _rtld_tls_offset_allocate(Obj_Entry *obj
>  	if (obj->tlsalign > _rtld_tls_static_max_align) {
>  		_rtld_tls_static_max_align = obj->tlsalign;
>  	}
> +	assert(_rtld_tls_static_max_align != 0);
> +	assert((_rtld_tls_static_max_align & (_rtld_tls_static_max_align - 1))
> +	    == 0);
> +	assert(ALIGNED_P(_rtld_tls_static_max_align, obj->tlsalign));
> +	assert(ALIGNED_P(_rtld_tls_static_max_align, alignof(max_align_t)));
> +	assert(ALIGNED_P(_rtld_tls_static_max_align, alignof(struct tls_tcb)));
> +
>  	obj->tlsoffset = offset;
>  	dbg(("%s: static tls offset 0x%zx size %zu align %zu (%zx/%zx)",
>  	    obj->path, obj->tlsoffset, obj->tlssize, obj->tlsalign,
>
> Index: src/libexec/ld.elf_so/xmalloc.c
> diff -u src/libexec/ld.elf_so/xmalloc.c:1.27 src/libexec/ld.elf_so/xmalloc.c:1.28
> --- src/libexec/ld.elf_so/xmalloc.c:1.27	Sun Jul 19 19:55:24 2026
> +++ src/libexec/ld.elf_so/xmalloc.c	Mon Jul 20 18:46:37 2026
> @@ -1,4 +1,4 @@
> -/*	$NetBSD: xmalloc.c,v 1.27 2026/07/19 19:55:24 riastradh Exp $	*/
> +/*	$NetBSD: xmalloc.c,v 1.28 2026/07/20 18:46:37 riastradh Exp $	*/
>  
>  /*
>   * Copyright 1996 John D. Polstra.
> @@ -77,7 +77,7 @@
>  
>  #include <sys/cdefs.h>
>  #ifndef lint
> -__RCSID("$NetBSD: xmalloc.c,v 1.27 2026/07/19 19:55:24 riastradh Exp $");
> +__RCSID("$NetBSD: xmalloc.c,v 1.28 2026/07/20 18:46:37 riastradh Exp $");
>  #endif /* not lint */
>  
>  #include <stdlib.h>
> @@ -230,6 +230,8 @@ xmalloc_aligned(size_t size, size_t alig
>  	union overhead *ov;
>  	uintptr_t x;
>  
> +	ASSERT((align & (align - 1)) == 0);
> +
>  	if (align < FIRST_BUCKET_SIZE)
>  		align = FIRST_BUCKET_SIZE;
>  	offset &= align - 1;
>

-- 
Ryo ONODERA // ryo%tetera.org@localhost
PGP fingerprint = 82A2 DC91 76E0 A10A 8ABB  FD1B F404 27FA C7D1 15F3