Commit 1ad3dcc0 authored by Luke Yang's avatar Luke Yang Committed by Linus Torvalds
Browse files

[PATCH] flat binary loader doesn't check fd table full 



In binfmt_flat.c, the flat binary loader should check file descriptor table
and install the fd on the file.

Convert the function to single-exit and fix this bug.

Signed-off-by: default avatar"Luke Yang" <luke.adi@gmail.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent f5163427

fs/binfmt_flat.c

+54 −19
Original line number Diff line number Diff line
@@ -36,6 +36,7 @@ 
#include <linux/personality.h>

#include <linux/init.h>

#include <linux/flat.h>

#include <linux/syscalls.h>



#include <asm/byteorder.h>

#include <asm/system.h>
@@ -426,6 +427,8 @@ static int load_flat_file(struct linux_binprm * bprm, 
	int i, rev, relocs = 0;

	loff_t fpos;

	unsigned long start_code, end_code;

	int ret;

	int exec_fileno;



	hdr = ((struct flat_hdr *) bprm->buf);		/* exec-header */

	inode = bprm->file->f_dentry->d_inode;
@@ -450,7 +453,8 @@ static int load_flat_file(struct linux_binprm * bprm, 
		 */

		if (strncmp(hdr->magic, "#!", 2))

			printk("BINFMT_FLAT: bad header magic\n");

		return -ENOEXEC;

		ret = -ENOEXEC;

		goto err;

	}



	if (flags & FLAT_FLAG_KTRACE)
@@ -458,14 +462,16 @@ static int load_flat_file(struct linux_binprm * bprm, 


	if (rev != FLAT_VERSION && rev != OLD_FLAT_VERSION) {

		printk("BINFMT_FLAT: bad flat file version 0x%x (supported 0x%x and 0x%x)\n", rev, FLAT_VERSION, OLD_FLAT_VERSION);

		return -ENOEXEC;

		ret = -ENOEXEC;

		goto err;

	}

	

	/* Don't allow old format executables to use shared libraries */

	if (rev == OLD_FLAT_VERSION && id != 0) {

		printk("BINFMT_FLAT: shared libraries are not available before rev 0x%x\n",

				(int) FLAT_VERSION);

		return -ENOEXEC;

		ret = -ENOEXEC;

		goto err;

	}



	/*
@@ -478,7 +484,8 @@ static int load_flat_file(struct linux_binprm * bprm, 
#ifndef CONFIG_BINFMT_ZFLAT

	if (flags & (FLAT_FLAG_GZIP|FLAT_FLAG_GZDATA)) {

		printk("Support for ZFLAT executables is not enabled.\n");

		return -ENOEXEC;

		ret = -ENOEXEC;

		goto err;

	}

#endif
@@ -490,14 +497,27 @@ static int load_flat_file(struct linux_binprm * bprm, 
	rlim = current->signal->rlim[RLIMIT_DATA].rlim_cur;

	if (rlim >= RLIM_INFINITY)

		rlim = ~0;

	if (data_len + bss_len > rlim)

		return -ENOMEM;

	if (data_len + bss_len > rlim) {

		ret = -ENOMEM;

		goto err;

	}



	/* check file descriptor */

	exec_fileno = get_unused_fd();

	if (exec_fileno < 0) {

		ret = -EMFILE;

		goto err;

	}

	get_file(bprm->file);

	fd_install(exec_fileno, bprm->file);



	/* Flush all traces of the currently running executable */

	if (id == 0) {

		result = flush_old_exec(bprm);

		if (result)

			return result;

		if (result) {

			ret = result;

			goto err_close;

		}



		/* OK, This is the point of no return */

		set_personality(PER_LINUX);
@@ -527,7 +547,8 @@ static int load_flat_file(struct linux_binprm * bprm, 
			if (!textpos)

				textpos = (unsigned long) -ENOMEM;

			printk("Unable to mmap process text, errno %d\n", (int)-textpos);

			return(textpos);

			ret = textpos;

			goto err_close;

		}



		down_write(&current->mm->mmap_sem);
@@ -542,7 +563,8 @@ static int load_flat_file(struct linux_binprm * bprm, 
			printk("Unable to allocate RAM for process data, errno %d\n",

					(int)-datapos);

			do_munmap(current->mm, textpos, text_len);

			return realdatastart;

			ret = realdatastart;

			goto err_close;

		}

		datapos = realdatastart + MAX_SHARED_LIBS * sizeof(unsigned long);
@@ -564,7 +586,8 @@ static int load_flat_file(struct linux_binprm * bprm, 
			printk("Unable to read data+bss, errno %d\n", (int)-result);

			do_munmap(current->mm, textpos, text_len);

			do_munmap(current->mm, realdatastart, data_len + extra);

			return result;

			ret = result;

			goto err_close;

		}



		reloc = (unsigned long *) (datapos+(ntohl(hdr->reloc_start)-text_len));
@@ -582,7 +605,8 @@ static int load_flat_file(struct linux_binprm * bprm, 
				textpos = (unsigned long) -ENOMEM;

			printk("Unable to allocate RAM for process text/data, errno %d\n",

					(int)-textpos);

			return(textpos);

			ret = textpos;

			goto err_close;

		}



		realdatastart = textpos + ntohl(hdr->data_start);
@@ -627,7 +651,8 @@ static int load_flat_file(struct linux_binprm * bprm, 
			printk("Unable to read code+data+bss, errno %d\n",(int)-result);

			do_munmap(current->mm, textpos, text_len + data_len + extra +

				MAX_SHARED_LIBS * sizeof(unsigned long));

			return result;

			ret = result;

			goto err_close;

		}

	}
@@ -690,8 +715,10 @@ static int load_flat_file(struct linux_binprm * bprm, 
			unsigned long addr;

			if (*rp) {

				addr = calc_reloc(*rp, libinfo, id, 0);

				if (addr == RELOC_FAILED)

					return -ENOEXEC;

				if (addr == RELOC_FAILED) {

					ret = -ENOEXEC;

					goto err_close;

				}

				*rp = addr;

			}

		}
@@ -718,8 +745,10 @@ static int load_flat_file(struct linux_binprm * bprm, 
			relval = ntohl(reloc[i]);

			addr = flat_get_relocate_addr(relval);

			rp = (unsigned long *) calc_reloc(addr, libinfo, id, 1);

			if (rp == (unsigned long *)RELOC_FAILED)

				return -ENOEXEC;

			if (rp == (unsigned long *)RELOC_FAILED) {

				ret = -ENOEXEC;

				goto err_close;

			}



			/* Get the pointer's value.  */

			addr = flat_get_addr_from_rp(rp, relval, flags);
@@ -731,8 +760,10 @@ static int load_flat_file(struct linux_binprm * bprm, 
				if ((flags & FLAT_FLAG_GOTPIC) == 0)

					addr = ntohl(addr);

				addr = calc_reloc(addr, libinfo, id, 0);

				if (addr == RELOC_FAILED)

					return -ENOEXEC;

				if (addr == RELOC_FAILED) {

					ret = -ENOEXEC;

					goto err_close;

				}



				/* Write back the relocated pointer.  */

				flat_put_addr_at_rp(rp, addr, relval);
@@ -752,6 +783,10 @@ static int load_flat_file(struct linux_binprm * bprm, 
			stack_len);



	return 0;

err_close:

	sys_close(exec_fileno);

err:

	return ret;

}

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