Commit cf9a566c authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Greg Ungerer
Browse files

binfmt_flat: make support for old format binaries optional 



No need to carry the extra code around, given that systems using flat
binaries are generally very resource constrained.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarGreg Ungerer <gerg@linux-m68k.org>
parent aef0f78e

fs/Kconfig.binfmt

+7 −0
Original line number Diff line number Diff line
@@ -106,6 +106,13 @@ config BINFMT_FLAT_ARGVP_ENVP_ON_STACK 
config BINFMT_FLAT_OLD_ALWAYS_RAM

	bool



config BINFMT_FLAT_OLD

	bool "Enable support for very old legacy flat binaries"

	depends on BINFMT_FLAT

	help

	  Support decade old uClinux FLAT format binaries.  Unless you know

	  you have some of those say N here.



config BINFMT_ZFLAT

	bool "Enable ZFLAT support"

	depends on BINFMT_FLAT

fs/binfmt_flat.c

+22 −8
Original line number Diff line number Diff line
@@ -374,6 +374,7 @@ calc_reloc(unsigned long r, struct lib_info *p, int curid, int internalp) 


/****************************************************************************/



#ifdef CONFIG_BINFMT_FLAT_OLD

static void old_reloc(unsigned long rl)

{

	static const char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" };
@@ -411,6 +412,7 @@ static void old_reloc(unsigned long rl) 


	pr_debug("Relocation became %lx\n", val);

}

#endif /* CONFIG_BINFMT_FLAT_OLD */



/****************************************************************************/
@@ -461,6 +463,7 @@ static int load_flat_file(struct linux_binprm *bprm, 
	if (flags & FLAT_FLAG_KTRACE)

		pr_info("Loading file: %s\n", bprm->filename);



#ifdef CONFIG_BINFMT_FLAT_OLD

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

		pr_err("bad flat file version 0x%x (supported 0x%lx and 0x%lx)\n",

		       rev, FLAT_VERSION, OLD_FLAT_VERSION);
@@ -476,6 +479,23 @@ static int load_flat_file(struct linux_binprm *bprm, 
		goto err;

	}



	/*

	 * fix up the flags for the older format,  there were all kinds

	 * of endian hacks,  this only works for the simple cases

	 */

	if (rev == OLD_FLAT_VERSION &&

	   (flags || IS_ENABLED(CONFIG_BINFMT_FLAT_OLD_ALWAYS_RAM)))

		flags = FLAT_FLAG_RAM;



#else /* CONFIG_BINFMT_FLAT_OLD */

	if (rev != FLAT_VERSION) {

		pr_err("bad flat file version 0x%x (supported 0x%lx)\n",

		       rev, FLAT_VERSION);

		ret = -ENOEXEC;

		goto err;

	}

#endif /* !CONFIG_BINFMT_FLAT_OLD */



	/*

	 * Make sure the header params are sane.

	 * 28 bits (256 MB) is way more than reasonable in this case.
@@ -487,14 +507,6 @@ static int load_flat_file(struct linux_binprm *bprm, 
		goto err;

	}



	/*

	 * fix up the flags for the older format,  there were all kinds

	 * of endian hacks,  this only works for the simple cases

	 */

	if (rev == OLD_FLAT_VERSION &&

	   (flags || IS_ENABLED(CONFIG_BINFMT_FLAT_OLD_ALWAYS_RAM)))

		flags = FLAT_FLAG_RAM;



#ifndef CONFIG_BINFMT_ZFLAT

	if (flags & (FLAT_FLAG_GZIP|FLAT_FLAG_GZDATA)) {

		pr_err("Support for ZFLAT executables is not enabled.\n");
@@ -833,6 +845,7 @@ static int load_flat_file(struct linux_binprm *bprm, 
					goto err;

			}

		}

#ifdef CONFIG_BINFMT_FLAT_OLD

	} else {

		for (i = 0; i < relocs; i++) {

			__be32 relval;
@@ -840,6 +853,7 @@ static int load_flat_file(struct linux_binprm *bprm, 
				return -EFAULT;

			old_reloc(ntohl(relval));

		}

#endif /* CONFIG_BINFMT_FLAT_OLD */

	}



	flush_icache_range(start_code, end_code);