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: Christoph Hellwig <hch@lst.de>
Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
This commit is contained in:
Christoph Hellwig 2019-06-13 09:08:58 +02:00 committed by Greg Ungerer
parent aef0f78e74
commit cf9a566c2c
2 changed files with 29 additions and 8 deletions

View File

@ -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

View File

@ -374,6 +374,7 @@ failed:
/****************************************************************************/
#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);