From 7e7ec6a934349ef6983f06f7ac0da09cc8a42983 Mon Sep 17 00:00:00 2001 From: Nicolas Pitre Date: Sun, 24 Jul 2016 11:30:18 -0400 Subject: elf_fdpic_transfer_args_to_stack(): make it generic This copying of arguments and environment is common to both NOMMU binary formats we support. Let's make the elf_fdpic version available to the flat format as well. While at it, improve the code a bit not to copy below the actual data area. Signed-off-by: Nicolas Pitre Reviewed-by: Greg Ungerer Signed-off-by: Greg Ungerer --- fs/binfmt_elf_fdpic.c | 38 ++------------------------------------ fs/exec.c | 33 +++++++++++++++++++++++++++++++++ 2 files changed, 35 insertions(+), 36 deletions(-) (limited to 'fs') diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c index 203589311bf8..464a972e88c1 100644 --- a/fs/binfmt_elf_fdpic.c +++ b/fs/binfmt_elf_fdpic.c @@ -67,8 +67,6 @@ static int create_elf_fdpic_tables(struct linux_binprm *, struct mm_struct *, struct elf_fdpic_params *); #ifndef CONFIG_MMU -static int elf_fdpic_transfer_args_to_stack(struct linux_binprm *, - unsigned long *); static int elf_fdpic_map_file_constdisp_on_uclinux(struct elf_fdpic_params *, struct file *, struct mm_struct *); @@ -515,8 +513,9 @@ static int create_elf_fdpic_tables(struct linux_binprm *bprm, sp = mm->start_stack; /* stack the program arguments and environment */ - if (elf_fdpic_transfer_args_to_stack(bprm, &sp) < 0) + if (transfer_args_to_stack(bprm, &sp) < 0) return -EFAULT; + sp &= ~15; #endif /* @@ -709,39 +708,6 @@ static int create_elf_fdpic_tables(struct linux_binprm *bprm, return 0; } -/*****************************************************************************/ -/* - * transfer the program arguments and environment from the holding pages onto - * the stack - */ -#ifndef CONFIG_MMU -static int elf_fdpic_transfer_args_to_stack(struct linux_binprm *bprm, - unsigned long *_sp) -{ - unsigned long index, stop, sp; - char *src; - int ret = 0; - - stop = bprm->p >> PAGE_SHIFT; - sp = *_sp; - - for (index = MAX_ARG_PAGES - 1; index >= stop; index--) { - src = kmap(bprm->page[index]); - sp -= PAGE_SIZE; - if (copy_to_user((void *) sp, src, PAGE_SIZE) != 0) - ret = -EFAULT; - kunmap(bprm->page[index]); - if (ret < 0) - goto out; - } - - *_sp = (*_sp - (MAX_ARG_PAGES * PAGE_SIZE - bprm->p)) & ~15; - -out: - return ret; -} -#endif - /*****************************************************************************/ /* * load the appropriate binary image (executable or interpreter) into memory diff --git a/fs/exec.c b/fs/exec.c index 887c1c955df8..ef0df2f09257 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -762,6 +762,39 @@ out_unlock: } EXPORT_SYMBOL(setup_arg_pages); +#else + +/* + * Transfer the program arguments and environment from the holding pages + * onto the stack. The provided stack pointer is adjusted accordingly. + */ +int transfer_args_to_stack(struct linux_binprm *bprm, + unsigned long *sp_location) +{ + unsigned long index, stop, sp; + int ret = 0; + + stop = bprm->p >> PAGE_SHIFT; + sp = *sp_location; + + for (index = MAX_ARG_PAGES - 1; index >= stop; index--) { + unsigned int offset = index == stop ? bprm->p & ~PAGE_MASK : 0; + char *src = kmap(bprm->page[index]) + offset; + sp -= PAGE_SIZE - offset; + if (copy_to_user((void *) sp, src, PAGE_SIZE - offset) != 0) + ret = -EFAULT; + kunmap(bprm->page[index]); + if (ret) + goto out; + } + + *sp_location = sp; + +out: + return ret; +} +EXPORT_SYMBOL(transfer_args_to_stack); + #endif /* CONFIG_MMU */ static struct file *do_open_execat(int fd, struct filename *name, int flags) -- cgit v1.2.3