diff --git a/package/uclibc/0001-pagesize-restore-PAGE_SHIFT-fallback-for-binfmt_flat.patch b/package/uclibc/0001-pagesize-restore-PAGE_SHIFT-fallback-for-binfmt_flat.patch new file mode 100644 index 0000000000..fdfd286042 --- /dev/null +++ b/package/uclibc/0001-pagesize-restore-PAGE_SHIFT-fallback-for-binfmt_flat.patch @@ -0,0 +1,169 @@ +From 7730f0d05a51cd89a7123bd696e4638c3c035d7b Mon Sep 17 00:00:00 2001 +From: Ramin Moussavi +Date: Fri, 29 May 2026 19:47:34 +0200 +Subject: [PATCH] pagesize: restore PAGE_SHIFT fallback for binfmt_flat (no + auxv) + +binfmt_flat builds the initial process stack from only argc/argv/envp; +it does not place an auxiliary vector. Commit 487af1498 ("drop +__pagesize, make _dl_pagesize the single source of truth") assumed +AT_PAGESZ is always supplied by the kernel and changed the _dl_pagesize +fallback from PAGE_SIZE to 0. On noMMU/FLAT targets that leaves +_dl_pagesize == 0, so every mmap-based malloc rounds its length to 0, +mmap() fails with EINVAL and the first allocation aborts -- busybox dies +with "init: out of memory" before it can run anything. + +Restore the fallback that arc/nds32 bits/uClibc_page.h have always +documented ("_dl_pagesize = auxvt[AT_PAGESZ].a_un.a_val ? : PAGE_SIZE"), +expressed as (1UL << PAGE_SHIFT) so it keeps working now that PAGE_SIZE +is no longer defined in : + + - Seed _dl_pagesize with (1UL << PAGE_SHIFT) at its definition in the + two translation units that own the symbol: the dynamic linker + (ldso.c, used by ld.so) and the static-libc support (dl-support.c). + - Override it from AT_PAGESZ only when that entry is actually present + (a_type == AT_PAGESZ) and non-zero, instead of unconditionally + resetting it to 0. + +libdl.c (!SHARED) previously also defined _dl_pagesize. That was +harmless while dl-support.c's definition was tentative (the two merged), +but giving both a non-zero initializer makes them two strong .data +definitions, which collide as "multiple definition of `_dl_pagesize'" +when a static link pulls both objects out of libc.a (e.g. NPTL builds +that drag in libdl). Drop the redundant libdl.c definition: dl-support.c +is always co-linked from libc.a and provides the symbol. + +For FLAT, skip the aux-vector scan in __uClibc_main() altogether: there +is nothing valid past the envp NULL, so _dl_aux_init() is not called and +_dl_auxv_start stays NULL. Guard getauxval()'s slow-path loop against +that NULL so a lookup of an uncached (>= AUX_MAX_AT_ID) tag returns +ENOENT instead of dereferencing NULL. + +Verified on riscv32 noMMU/FLAT (gcc 15.2.0, linux 6.18.33): busybox +boots as init and the testsuite runs (was "init: out of memory" +before). Dynamic + NPTL links are unaffected -- x86_64 NPTL static +busybox links cleanly and ld-uClibc loads the testsuite. + +Upstream: https://gogs.waldemar-brodkorb.de/oss/uclibc-ng/commit/7730f0d05a51cd89a7123bd696e4638c3c035d7b +Signed-off-by: Ramin Moussavi +Signed-off-by: Waldemar Brodkorb +--- + ldso/ldso/ldso.c | 7 ++++--- + ldso/libdl/libdl.c | 2 +- + libc/misc/auxvt/getauxval.c | 3 ++- + libc/misc/elf/dl-support.c | 7 ++++--- + libc/misc/internals/__uClibc_main.c | 7 +++++-- + 5 files changed, 16 insertions(+), 10 deletions(-) + +diff --git a/ldso/ldso/ldso.c b/ldso/ldso/ldso.c +index 9c00e4a61..55f7d7e45 100755 +--- a/ldso/ldso/ldso.c ++++ b/ldso/ldso/ldso.c +@@ -52,7 +52,7 @@ char *_dl_library_path = NULL; /* Where we look for libraries */ + char *_dl_preload = NULL; /* Things to be loaded before the libs */ + #endif + int _dl_errno = 0; /* We can't use the real errno in ldso */ +-size_t _dl_pagesize = 0; /* Store the page size for use later */ ++size_t _dl_pagesize = (1UL << PAGE_SHIFT); /* fallback; overridden from AT_PAGESZ if present */ + struct r_debug *_dl_debug_addr = NULL; /* Used to communicate with the gdb debugger */ + void *(*_dl_malloc_function) (size_t size) = NULL; + void (*_dl_free_function) (void *p) = NULL; +@@ -460,8 +460,9 @@ void *_dl_get_ready_to_run(struct elf_resolve *tpnt, DL_LOADADDR_TYPE load_addr, + + _dl_memset(app_tpnt, 0, sizeof(*app_tpnt)); + +- /* Store the page size for later use */ +- _dl_pagesize = (_dl_auxvt[AT_PAGESZ].a_un.a_val) ? (size_t) _dl_auxvt[AT_PAGESZ].a_un.a_val : 0; ++ /* Override the fallback only if AT_PAGESZ is present and non-zero */ ++ if (_dl_auxvt[AT_PAGESZ].a_type == AT_PAGESZ && _dl_auxvt[AT_PAGESZ].a_un.a_val) ++ _dl_pagesize = (size_t) _dl_auxvt[AT_PAGESZ].a_un.a_val; + /* Make it so _dl_malloc can use the page of memory we have already + * allocated. We shouldn't need to grab any more memory. This must + * be first since things like _dl_dprintf() use _dl_malloc()... +diff --git a/ldso/libdl/libdl.c b/ldso/libdl/libdl.c +index b78d6d9a3..f28801d7b 100644 +--- a/ldso/libdl/libdl.c ++++ b/ldso/libdl/libdl.c +@@ -109,7 +109,7 @@ void (*_dl_free_function) (void *p); + char *_dl_library_path = NULL; /* Where we look for libraries */ + #endif + int _dl_errno = 0; /* We can't use the real errno in ldso */ +-size_t _dl_pagesize = 0; /* Store the page size for use later */ ++/* _dl_pagesize is provided by dl-support.c (always co-linked from libc.a) */ + /* This global variable is also to communicate with debuggers such as gdb. */ + struct r_debug *_dl_debug_addr = NULL; + +diff --git a/libc/misc/auxvt/getauxval.c b/libc/misc/auxvt/getauxval.c +index 7610b7e5c..4af637071 100755 +--- a/libc/misc/auxvt/getauxval.c ++++ b/libc/misc/auxvt/getauxval.c +@@ -33,7 +33,8 @@ unsigned long int __getauxval (unsigned long int __type) + } + + // Otherwise we have to iterate the auxiliary vector. +- for (ElfW(auxv_t) *entry = _dl_auxv_start; entry->a_type != AT_NULL; entry++) ++ // _dl_auxv_start is NULL when there is no aux vector (e.g. FLAT). ++ for (ElfW(auxv_t) *entry = _dl_auxv_start; entry && entry->a_type != AT_NULL; entry++) + if (entry->a_type == __type) + return entry->a_un.a_val; + +diff --git a/libc/misc/elf/dl-support.c b/libc/misc/elf/dl-support.c +index 738f0ed3a..7ad57c090 100644 +--- a/libc/misc/elf/dl-support.c ++++ b/libc/misc/elf/dl-support.c +@@ -30,7 +30,7 @@ void (*_dl_init_static_tls) (struct link_map *) = &_dl_nothread_init_static_tls; + + ElfW(Phdr) *_dl_phdr; + size_t _dl_phnum; +-size_t _dl_pagesize; ++size_t _dl_pagesize = (1UL << PAGE_SHIFT); /* fallback; overridden from AT_PAGESZ if present */ + + ElfW(auxv_t) _dl_auxvt[AUX_MAX_AT_ID]; + ElfW(auxv_t) *_dl_auxv_start; +@@ -52,8 +52,9 @@ void internal_function _dl_aux_init (ElfW(auxv_t) *av) + /* Get the number of program headers from the aux vect */ + _dl_phnum = (size_t) _dl_auxvt[AT_PHNUM].a_un.a_val; + +- /* Get the pagesize from the aux vect */ +- _dl_pagesize = (_dl_auxvt[AT_PAGESZ].a_un.a_val) ? (size_t) _dl_auxvt[AT_PAGESZ].a_un.a_val : 0; ++ /* Override the fallback only if AT_PAGESZ is present and non-zero */ ++ if (_dl_auxvt[AT_PAGESZ].a_type == AT_PAGESZ && _dl_auxvt[AT_PAGESZ].a_un.a_val) ++ _dl_pagesize = (size_t) _dl_auxvt[AT_PAGESZ].a_un.a_val; + } + + #if defined(USE_TLS) && USE_TLS +diff --git a/libc/misc/internals/__uClibc_main.c b/libc/misc/internals/__uClibc_main.c +index 35cb73fcc..549606505 100644 +--- a/libc/misc/internals/__uClibc_main.c ++++ b/libc/misc/internals/__uClibc_main.c +@@ -369,7 +369,7 @@ void __uClibc_main(int (*main)(int, char **, char **), int argc, + char **argv, void (*app_init)(void), void (*app_fini)(void), + void (*rtld_fini)(void), void *stack_end attribute_unused) + { +-#ifndef SHARED ++#if !defined(SHARED) && !defined(__UCLIBC_FORMAT_FLAT__) + unsigned long *aux_dat; + #endif + +@@ -395,7 +395,9 @@ void __uClibc_main(int (*main)(int, char **, char **), int argc, + } + + #ifndef SHARED +- /* Pull stuff from the ELF header when possible */ ++# ifndef __UCLIBC_FORMAT_FLAT__ ++ /* Pull stuff from the ELF header when possible. binfmt_flat passes no ++ aux vector, so skip this for FLAT. */ + aux_dat = (unsigned long*)__environ; + while (*aux_dat) { + aux_dat++; +@@ -404,6 +406,7 @@ void __uClibc_main(int (*main)(int, char **, char **), int argc, + /* Get the program headers (_dl_phdr) from the aux vector + It will be used into __libc_setup_tls. */ + _dl_aux_init ((ElfW(auxv_t) *)aux_dat); ++# endif + #endif + + /* We need to initialize uClibc. If we are dynamically linked this +-- +2.47.3 +