linux-toradex.git/usr/gen_init_cpio.c, branch v3.2.73

gen_init_cpio: avoid stack overflow when expanding

2012-10-30T23:27:07+00:00

commit 20f1de659b77364d55d4e7fad2ef657e7730323f upstream.

Fix possible overflow of the buffer used for expanding environment
variables when building file list.

In the extremely unlikely case of an attacker having control over the
environment variables visible to gen_init_cpio, control over the
contents of the file gen_init_cpio parses, and gen_init_cpio was built
without compiler hardening, the attacker can gain arbitrary execution
control via a stack buffer overflow.

  $ cat usr/crash.list
  file foo ${BIG}${BIG}${BIG}${BIG}${BIG}${BIG} 0755 0 0
  $ BIG=$(perl -e 'print "A" x 4096;') ./usr/gen_init_cpio usr/crash.list
  *** buffer overflow detected ***: ./usr/gen_init_cpio terminated

This also replaces the space-indenting with tabs.

Patch based on existing fix extracted from grsecurity.

Signed-off-by: Kees Cook 
Cc: Michal Marek 
Cc: Brad Spengler 
Cc: PaX Team 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Ben Hutchings

initramfs: Use KBUILD_BUILD_TIMESTAMP for generated entries

2011-04-18T12:27:52+00:00

gen_init_cpio gets the current time and uses it for each symlink,
special file, and directory.  Grab the current time once and make it
possible to override it with the KBUILD_BUILD_TIMESTAMP variable for
reproducible builds.

Signed-off-by: Michal Marek

gen_init_cpio: checkpatch fixes

2011-01-05T22:49:53+00:00

Cc: Jesper Juhl 
Cc: Michal Marek 
Signed-off-by: Andrew Morton 
Signed-off-by: Michal Marek

gen_init_cpio: Avoid race between call to stat() and call to open()

2010-12-29T14:06:54+00:00

In usr/gen_init_cpio.c::cpio_mkfile() a call to stat() is made based on
pathname, subsequently the file is open()'ed and then the value of the
initial stat() call is used to allocate a buffer. This is not safe since
the file may change between the call to stat() and the call to open().
Safer to just open() the file and then do fstat() using the filedescriptor
returned by open.

Signed-off-by: Jesper Juhl 
Acked-by: Jeff Garzik 
Signed-off-by: Michal Marek

gen_init_cpio: remove leading `/' from file names

2010-12-02T13:28:50+00:00

When we extracted the generated cpio archive using "cpio -id" command,
it complained,

cpio: Removing leading `/' from member names
var/run
cpio: Removing leading `/' from member names
var/lib
cpio: Removing leading `/' from member names
var/lib/misc

It is worse with the latest "cpio" or "pax", which tries to overwrite
the host file system with the leading '/'.

So the leading '/' of file names should be removed. This is consistent
with the initramfs come with major distributions such as Fedora or
Debian, etc.

Signed-off-by: Thomas Chou 
Acked-by: Mike Frysinger
Signed-off-by: Michal Marek

gen_init_cpio: fixed fwrite warning

2009-12-12T12:08:17+00:00

On compilers with security warnings enabled by default, we get:

usr/gen_init_cpio.c: In function ‘cpio_mkfile’:
usr/gen_init_cpio.c:357: warning: ignoring return value of ‘fwrite’,
                                  declared with attribute warn_unused_result

So check the return value and handle errors accordingly.

Signed-off-by: Mike Frysinger 
Signed-off-by: Michal Marek

Fix all -Wmissing-prototypes warnings in x86 defconfig

2009-09-23T14:39:28+00:00

Signed-off-by: Trevor Keith 
Cc: Sam Ravnborg 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

kbuild: gen_init_cpio expands shell variables in file names

2008-12-03T20:32:03+00:00

Modify gen_init_cpio so that lines that specify files can contain
what looks like a shell variable that's expanded during processing.

For example:

   file /sbin/kinit ${RFS_BASE}/usr/src/klibc/kinit/kinit 0755 0 0

given RFS_BASE is "/some/directory" in the environment

would be expanded to

   file /sbin/kinit /some/directory/usr/src/klibc/kinit/kinit 0755 0 0

If several environment variables appear in a line, they are all expanded
with processing happening from left to right.
Undefined variables expand to a null string.
Syntax errors stop processing, letting the existing error handling
show the user offending line.

This patch helps embedded folks who frequently create several
RFS directories and then switch between them as they're tuning
an initramfs.

Signed-off-by: gene.sally@timesys.com
Signed-off-by: Sam Ravnborg

kbuild: add support for reading stdin with gen_init_cpio

2007-07-16T19:15:52+00:00

Treat an argument of "-" as meaning "read stdin for cpio files" so
gen_init_cpio can be piped into.

Signed-off-by: Mike Frysinger 
Signed-off-by: Andrew Morton 
Signed-off-by: Sam Ravnborg

[PATCH] usr/gen_init_cpio.c: support for hard links

2007-02-11T18:51:25+00:00

Extend usr/gen_init_cpio.c "file" entry, adding support for hard links.

Previous format:
file     

New format:
file      []

The hard links specification is optional, keeping the previous
behaviour.

All hard links are defined sequentially in the resulting cpio and the
file data is present only in the last link. This is the behaviour of
GNU's cpio and is supported by the kernel initramfs extractor.

Signed-off-by: Luciano Rocha 
Cc: Al Viro 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds