diff options
Diffstat (limited to 'elf/dl-map-segments.h')
| -rw-r--r-- | elf/dl-map-segments.h | 72 |
1 files changed, 60 insertions, 12 deletions
diff --git a/elf/dl-map-segments.h b/elf/dl-map-segments.h index 024175b2d5..ce51585ce4 100644 --- a/elf/dl-map-segments.h +++ b/elf/dl-map-segments.h @@ -18,15 +18,18 @@ <https://www.gnu.org/licenses/>. */ #include <dl-load.h> +#ifdef __CHERI_PURE_CAPABILITY__ +# include <cheri_perms.h> +#endif /* Map a segment and align it properly. */ -static __always_inline ElfW(Addr) +static __always_inline elfptr_t _dl_map_segment (const struct loadcmd *c, ElfW(Addr) mappref, const size_t maplength, int fd) { if (__glibc_likely (c->mapalign <= GLRO(dl_pagesize))) - return (ElfW(Addr)) __mmap ((void *) mappref, maplength, c->prot, + return (elfptr_t) __mmap ((void *) mappref, maplength, c->prot, MAP_COPY|MAP_FILE, fd, c->mapoff); /* If the segment alignment > the page size, allocate enough space to @@ -34,15 +37,15 @@ _dl_map_segment (const struct loadcmd *c, ElfW(Addr) mappref, ElfW(Addr) maplen = (maplength >= c->mapalign ? (maplength + c->mapalign) : (2 * c->mapalign)); - ElfW(Addr) map_start = (ElfW(Addr)) __mmap ((void *) mappref, maplen, + elfptr_t map_start = (elfptr_t) __mmap ((void *) mappref, maplen, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0); if (__glibc_unlikely ((void *) map_start == MAP_FAILED)) return map_start; - ElfW(Addr) map_start_aligned = ALIGN_UP (map_start, c->mapalign); - map_start_aligned = (ElfW(Addr)) __mmap ((void *) map_start_aligned, + elfptr_t map_start_aligned = ALIGN_UP (map_start, c->mapalign); + map_start_aligned = (elfptr_t) __mmap ((void *) map_start_aligned, maplength, c->prot, MAP_COPY|MAP_FILE|MAP_FIXED, fd, c->mapoff); @@ -54,7 +57,7 @@ _dl_map_segment (const struct loadcmd *c, ElfW(Addr) mappref, ElfW(Addr) delta = map_start_aligned - map_start; if (delta) __munmap ((void *) map_start, delta); - ElfW(Addr) map_end = map_start_aligned + maplength; + elfptr_t map_end = map_start + (map_start_aligned - map_start) + maplength; map_end = ALIGN_UP (map_end, GLRO(dl_pagesize)); delta = map_start + maplen - map_end; if (delta) @@ -79,6 +82,10 @@ _dl_map_segments (struct link_map *l, int fd, struct link_map *loader) { const struct loadcmd *c = loadcmds; +#ifdef __CHERI_PURE_CAPABILITY__ + ElfW(Addr) rw_start = -1; + ElfW(Addr) rw_end = 0; +#endif if (__glibc_likely (type == ET_DYN)) { @@ -116,7 +123,7 @@ _dl_map_segments (struct link_map *l, int fd, c->mapend)) return N_("ELF load command address/offset not page-aligned"); if (__glibc_unlikely - (__mprotect ((caddr_t) (l->l_addr + c->mapend), + (__mprotect ((caddr_t) dl_rx_ptr (l, c->mapend), loadcmds[nloadcmds - 1].mapstart - c->mapend, PROT_NONE) < 0)) return DL_MAP_SEGMENTS_ERROR_MPROTECT; @@ -126,6 +133,22 @@ _dl_map_segments (struct link_map *l, int fd, goto postmap; } +#ifdef __CHERI_PURE_CAPABILITY__ + else + { + /* Need a single capability to cover all load segments. */ + void *p = __mmap ((void *) c->mapstart, maplength, c->prot, + MAP_FIXED|MAP_COPY|MAP_FILE, + fd, c->mapoff); + if (p == MAP_FAILED) + return DL_MAP_SEGMENTS_ERROR_MAP_SEGMENT; + l->l_map_start = (elfptr_t) p; + l->l_map_end = l->l_map_start + maplength; + l->l_contiguous = !has_holes; + + goto postmap; + } +#endif /* Remember which part of the address space this object uses. */ l->l_map_start = c->mapstart + l->l_addr; @@ -134,10 +157,10 @@ _dl_map_segments (struct link_map *l, int fd, while (c < &loadcmds[nloadcmds]) { - if (c->mapend > c->mapstart + if (c->dataend > c->mapstart /* Map the segment contents from the file. */ - && (__mmap ((void *) (l->l_addr + c->mapstart), - c->mapend - c->mapstart, c->prot, + && (__mmap ((void *) dl_rx_ptr (l, c->mapstart), + c->dataend - c->mapstart, c->prot, MAP_FIXED|MAP_COPY|MAP_FILE, fd, c->mapoff) == MAP_FAILED)) @@ -146,13 +169,28 @@ _dl_map_segments (struct link_map *l, int fd, postmap: _dl_postprocess_loadcmd (l, header, c); +#ifdef __CHERI_PURE_CAPABILITY__ + if (c->prot & PROT_WRITE) + { + if (l->l_rw_count >= DL_MAX_RW_COUNT) + return DL_MAP_SEGMENTS_ERROR_MAP_SEGMENT; // TODO: right error code + if (c->mapstart < rw_start) + rw_start = c->mapstart; + if (c->allocend > rw_end) + rw_end = c->allocend; + l->l_rw_range[l->l_rw_count].start = l->l_addr + c->mapstart; + l->l_rw_range[l->l_rw_count].end = l->l_addr + c->allocend; + l->l_rw_count++; + } +#endif + if (c->allocend > c->dataend) { /* Extra zero pages should appear at the end of this segment, after the data mapped from the file. */ - ElfW(Addr) zero, zeroend, zeropage; + elfptr_t zero, zeroend, zeropage; - zero = l->l_addr + c->dataend; + zero = dl_rx_ptr (l, c->dataend); zeroend = l->l_addr + c->allocend; zeropage = ((zero + GLRO(dl_pagesize) - 1) & ~(GLRO(dl_pagesize) - 1)); @@ -194,6 +232,16 @@ _dl_map_segments (struct link_map *l, int fd, ++c; } +#ifdef __CHERI_PURE_CAPABILITY__ + if (l->l_rw_count > 0) + { + l->l_rw_start = __builtin_cheri_address_set (l->l_map_start, l->l_addr + rw_start); + l->l_rw_start = __builtin_cheri_bounds_set (l->l_rw_start, rw_end - rw_start); + l->l_rw_start = __builtin_cheri_perms_and (l->l_rw_start, CAP_PERM_MASK_RW); + } + l->l_map_start = __builtin_cheri_perms_and (l->l_map_start, CAP_PERM_MASK_RX); +#endif + /* Notify ELF_PREFERRED_ADDRESS that we have to load this one fixed. */ ELF_FIXED_ADDRESS (loader, c->mapstart); |