From c7aa8596de86fb667914ccb95c10495ad056ff96 Mon Sep 17 00:00:00 2001 From: Szabolcs Nagy Date: Mon, 22 Jun 2020 10:56:38 +0100 Subject: rtld: Clean up PT_NOTE and add PT_GNU_PROPERTY handling Add generic code to handle PT_GNU_PROPERTY notes. Invalid content is ignored, _dl_process_pt_gnu_property is always called after PT_LOAD segments are mapped and it has no failure modes. Currently only one NT_GNU_PROPERTY_TYPE_0 note is handled, which contains target specific properties: the _dl_process_gnu_property hook is called for each property. The old _dl_process_pt_note and _rtld_process_pt_note differ in how the program header is read. The old _dl_process_pt_note is called before PT_LOAD segments are mapped and _rtld_process_pt_note is called after PT_LOAD segments are mapped. The old _rtld_process_pt_note is removed and _dl_process_pt_note is always called after PT_LOAD segments are mapped and now it has no failure modes. The program headers are scanned backwards so that PT_NOTE can be skipped if PT_GNU_PROPERTY exists. Co-Authored-By: H.J. Lu Reviewed-by: Adhemerval Zanella --- sysdeps/x86/dl-prop.h | 47 +++++++---------------------------------------- 1 file changed, 7 insertions(+), 40 deletions(-) (limited to 'sysdeps/x86') diff --git a/sysdeps/x86/dl-prop.h b/sysdeps/x86/dl-prop.h index 516f88ea80..89911e19e2 100644 --- a/sysdeps/x86/dl-prop.h +++ b/sysdeps/x86/dl-prop.h @@ -19,8 +19,6 @@ #ifndef _DL_PROP_H #define _DL_PROP_H -#include - extern void _dl_cet_check (struct link_map *, const char *) attribute_hidden; extern void _dl_cet_open_check (struct link_map *) @@ -146,48 +144,17 @@ _dl_process_cet_property_note (struct link_map *l, #endif } -#ifdef FILEBUF_SIZE -static inline int __attribute__ ((unused)) -_dl_process_pt_note (struct link_map *l, const ElfW(Phdr) *ph, - int fd, struct filebuf *fbp) +static inline void __attribute__ ((unused)) +_dl_process_pt_note (struct link_map *l, const ElfW(Phdr) *ph) { -# if CET_ENABLED - const ElfW(Nhdr) *note; - ElfW(Nhdr) *note_malloced = NULL; - ElfW(Addr) size = ph->p_filesz; - - if (ph->p_offset + size <= (size_t) fbp->len) - note = (const void *) (fbp->buf + ph->p_offset); - else - { - if (size < __MAX_ALLOCA_CUTOFF) - note = alloca (size); - else - { - note_malloced = malloc (size); - note = note_malloced; - } - if (__pread64_nocancel (fd, (void *) note, size, ph->p_offset) != size) - { - if (note_malloced) - free (note_malloced); - return -1; - } - } - - _dl_process_cet_property_note (l, note, size, ph->p_align); - if (note_malloced) - free (note_malloced); -# endif - return 0; + const ElfW(Nhdr) *note = (const void *) (ph->p_vaddr + l->l_addr); + _dl_process_cet_property_note (l, note, ph->p_memsz, ph->p_align); } -#endif -static inline int __attribute__ ((unused)) -_rtld_process_pt_note (struct link_map *l, const ElfW(Phdr) *ph) +static inline int __attribute__ ((always_inline)) +_dl_process_gnu_property (struct link_map *l, uint32_t type, uint32_t datasz, + void *data) { - const ElfW(Nhdr) *note = (const void *) (ph->p_vaddr + l->l_addr); - _dl_process_cet_property_note (l, note, ph->p_memsz, ph->p_align); return 0; } -- cgit 1.4.1