diff options
| -rw-r--r-- | linux-user/elfload.c | 110 | ||||
| -rw-r--r-- | linux-user/flatload.c | 2 | ||||
| -rw-r--r-- | linux-user/linuxload.c | 7 | ||||
| -rw-r--r-- | linux-user/qemu.h | 7 | ||||
| -rw-r--r-- | linux-user/syscall.c | 6 |
5 files changed, 56 insertions, 76 deletions
diff --git a/linux-user/elfload.c b/linux-user/elfload.c index ad46530f83..fdae6a6cd1 100644 --- a/linux-user/elfload.c +++ b/linux-user/elfload.c @@ -1373,66 +1373,69 @@ static bool elf_check_ehdr(struct elfhdr *ehdr) * to be put directly into the top of new user memory. * */ -static abi_ulong copy_elf_strings(int argc,char ** argv, void **page, - abi_ulong p) +static abi_ulong copy_elf_strings(int argc, char **argv, char *scratch, + abi_ulong p, abi_ulong stack_limit) { - char *tmp, *tmp1, *pag = NULL; - int len, offset = 0; + char *tmp; + int len, offset; + abi_ulong top = p; if (!p) { return 0; /* bullet-proofing */ } + + offset = ((p - 1) % TARGET_PAGE_SIZE) + 1; + while (argc-- > 0) { tmp = argv[argc]; if (!tmp) { fprintf(stderr, "VFS: argc is wrong"); exit(-1); } - tmp1 = tmp; - while (*tmp++); - len = tmp - tmp1; - if (p < len) { /* this shouldn't happen - 128kB */ + len = strlen(tmp) + 1; + tmp += len; + + if (len > (p - stack_limit)) { return 0; } while (len) { - --p; --tmp; --len; - if (--offset < 0) { - offset = p % TARGET_PAGE_SIZE; - pag = (char *)page[p/TARGET_PAGE_SIZE]; - if (!pag) { - pag = g_try_malloc0(TARGET_PAGE_SIZE); - page[p/TARGET_PAGE_SIZE] = pag; - if (!pag) - return 0; - } - } - if (len == 0 || offset == 0) { - *(pag + offset) = *tmp; - } - else { - int bytes_to_copy = (len > offset) ? offset : len; - tmp -= bytes_to_copy; - p -= bytes_to_copy; - offset -= bytes_to_copy; - len -= bytes_to_copy; - memcpy_fromfs(pag + offset, tmp, bytes_to_copy + 1); + int bytes_to_copy = (len > offset) ? offset : len; + tmp -= bytes_to_copy; + p -= bytes_to_copy; + offset -= bytes_to_copy; + len -= bytes_to_copy; + + memcpy_fromfs(scratch + offset, tmp, bytes_to_copy); + + if (offset == 0) { + memcpy_to_target(p, scratch, top - p); + top = p; + offset = TARGET_PAGE_SIZE; } } } + if (offset) { + memcpy_to_target(p, scratch + offset, top - p); + } + return p; } -static abi_ulong setup_arg_pages(abi_ulong p, struct linux_binprm *bprm, +/* Older linux kernels provide up to MAX_ARG_PAGES (default: 32) of + * argument/environment space. Newer kernels (>2.6.33) allow more, + * dependent on stack size, but guarantee at least 32 pages for + * backwards compatibility. + */ +#define STACK_LOWER_LIMIT (32 * TARGET_PAGE_SIZE) + +static abi_ulong setup_arg_pages(struct linux_binprm *bprm, struct image_info *info) { - abi_ulong stack_base, size, error, guard; - int i; + abi_ulong size, error, guard; - /* Create enough stack to hold everything. If we don't use - it for args, we'll use it for something else. */ size = guest_stack_size; - if (size < MAX_ARG_PAGES*TARGET_PAGE_SIZE) { - size = MAX_ARG_PAGES*TARGET_PAGE_SIZE; + if (size < STACK_LOWER_LIMIT) { + size = STACK_LOWER_LIMIT; } guard = TARGET_PAGE_SIZE; if (guard < qemu_real_host_page_size) { @@ -1450,18 +1453,8 @@ static abi_ulong setup_arg_pages(abi_ulong p, struct linux_binprm *bprm, target_mprotect(error, guard, PROT_NONE); info->stack_limit = error + guard; - stack_base = info->stack_limit + size - MAX_ARG_PAGES*TARGET_PAGE_SIZE; - p += stack_base; - - for (i = 0 ; i < MAX_ARG_PAGES ; i++) { - if (bprm->page[i]) { - /* FIXME - check return value of memcpy_to_target() for failure */ - memcpy_to_target(stack_base, bprm->page[i], TARGET_PAGE_SIZE); - g_free(bprm->page[i]); - } - stack_base += TARGET_PAGE_SIZE; - } - return p; + + return info->stack_limit + size - sizeof(void *); } /* Map and zero the bss. We need to explicitly zero any fractional pages @@ -2203,6 +2196,7 @@ int load_elf_binary(struct linux_binprm *bprm, struct image_info *info) struct image_info interp_info; struct elfhdr elf_ex; char *elf_interpreter = NULL; + char *scratch; info->start_mmap = (abi_ulong)ELF_START_MMAP; @@ -2214,18 +2208,24 @@ int load_elf_binary(struct linux_binprm *bprm, struct image_info *info) when we load the interpreter. */ elf_ex = *(struct elfhdr *)bprm->buf; - bprm->p = copy_elf_strings(1, &bprm->filename, bprm->page, bprm->p); - bprm->p = copy_elf_strings(bprm->envc,bprm->envp,bprm->page,bprm->p); - bprm->p = copy_elf_strings(bprm->argc,bprm->argv,bprm->page,bprm->p); + /* Do this so that we can load the interpreter, if need be. We will + change some of these later */ + bprm->p = setup_arg_pages(bprm, info); + + scratch = g_new0(char, TARGET_PAGE_SIZE); + bprm->p = copy_elf_strings(1, &bprm->filename, scratch, + bprm->p, info->stack_limit); + bprm->p = copy_elf_strings(bprm->envc, bprm->envp, scratch, + bprm->p, info->stack_limit); + bprm->p = copy_elf_strings(bprm->argc, bprm->argv, scratch, + bprm->p, info->stack_limit); + g_free(scratch); + if (!bprm->p) { fprintf(stderr, "%s: %s\n", bprm->filename, strerror(E2BIG)); exit(-1); } - /* Do this so that we can load the interpreter, if need be. We will - change some of these later */ - bprm->p = setup_arg_pages(bprm->p, bprm, info); - if (elf_interpreter) { load_elf_interp(elf_interpreter, &interp_info, bprm->buf); diff --git a/linux-user/flatload.c b/linux-user/flatload.c index 566a7a87a3..ceacb9844a 100644 --- a/linux-user/flatload.c +++ b/linux-user/flatload.c @@ -707,7 +707,7 @@ static int load_flat_shared_library(int id, struct lib_info *libs) int load_flt_binary(struct linux_binprm *bprm, struct image_info *info) { struct lib_info libinfo[MAX_SHARED_LIBS]; - abi_ulong p = bprm->p; + abi_ulong p; abi_ulong stack_len; abi_ulong start_addr; abi_ulong sp; diff --git a/linux-user/linuxload.c b/linux-user/linuxload.c index 506e837ae1..dbaf0ec586 100644 --- a/linux-user/linuxload.c +++ b/linux-user/linuxload.c @@ -135,10 +135,7 @@ int loader_exec(int fdexec, const char *filename, char **argv, char **envp, struct linux_binprm *bprm) { int retval; - int i; - bprm->p = TARGET_PAGE_SIZE*MAX_ARG_PAGES-sizeof(unsigned int); - memset(bprm->page, 0, sizeof(bprm->page)); bprm->fd = fdexec; bprm->filename = (char *)filename; bprm->argc = count(argv); @@ -172,9 +169,5 @@ int loader_exec(int fdexec, const char *filename, char **argv, char **envp, return retval; } - /* Something went wrong, return the inode and free the argument pages*/ - for (i=0 ; i<MAX_ARG_PAGES ; i++) { - g_free(bprm->page[i]); - } return(retval); } diff --git a/linux-user/qemu.h b/linux-user/qemu.h index 678e5d602e..bd90cc3799 100644 --- a/linux-user/qemu.h +++ b/linux-user/qemu.h @@ -143,12 +143,6 @@ extern const char *qemu_uname_release; extern unsigned long mmap_min_addr; /* ??? See if we can avoid exposing so much of the loader internals. */ -/* - * MAX_ARG_PAGES defines the number of pages allocated for arguments - * and envelope for the new program. 32 should suffice, this gives - * a maximum env+arg of 128kB w/4KB pages! - */ -#define MAX_ARG_PAGES 33 /* Read a good amount of data initially, to hopefully get all the program headers loaded. */ @@ -160,7 +154,6 @@ extern unsigned long mmap_min_addr; */ struct linux_binprm { char buf[BPRM_BUF_SIZE] __attribute__((aligned)); - void *page[MAX_ARG_PAGES]; abi_ulong p; int fd; int e_uid, e_gid; diff --git a/linux-user/syscall.c b/linux-user/syscall.c index d1d3eb2d78..7fbaa8bb67 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -5808,12 +5808,6 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1, } *q = NULL; - /* This case will not be caught by the host's execve() if its - page size is bigger than the target's. */ - if (total_size > MAX_ARG_PAGES * TARGET_PAGE_SIZE) { - ret = -TARGET_E2BIG; - goto execve_end; - } if (!(p = lock_user_string(arg1))) goto execve_efault; ret = get_errno(execve(p, argp, envp)); |