Revision e6838a29ecb484c97e4efef9429643b9851fba6e authored by J. Bruce Fields on 21 April 2017, 20:10:18 UTC, committed by J. Bruce Fields on 25 April 2017, 20:34:37 UTC
A client can append random data to the end of an NFSv2 or NFSv3 RPC call without our complaining; we'll just stop parsing at the end of the expected data and ignore the rest. Encoded arguments and replies are stored together in an array of pages, and if a call is too large it could leave inadequate space for the reply. This is normally OK because NFS RPC's typically have either short arguments and long replies (like READ) or long arguments and short replies (like WRITE). But a client that sends an incorrectly long reply can violate those assumptions. This was observed to cause crashes. Also, several operations increment rq_next_page in the decode routine before checking the argument size, which can leave rq_next_page pointing well past the end of the page array, causing trouble later in svc_free_pages. So, following a suggestion from Neil Brown, add a central check to enforce our expectation that no NFSv2/v3 call has both a large call and a large reply. As followup we may also want to rewrite the encoding routines to check more carefully that they aren't running off the end of the page array. We may also consider rejecting calls that have any extra garbage appended. That would be safer, and within our rights by spec, but given the age of our server and the NFS protocol, and the fact that we've never enforced this before, we may need to balance that against the possibility of breaking some oddball client. Reported-by: Tuomas Haanpää <thaan@synopsys.com> Reported-by: Ari Kauppi <ari@synopsys.com> Cc: stable@vger.kernel.org Reviewed-by: NeilBrown <neilb@suse.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
1 parent 5a7ad11
diffconfig
#!/usr/bin/python
#
# diffconfig - a tool to compare .config files.
#
# originally written in 2006 by Matt Mackall
# (at least, this was in his bloatwatch source code)
# last worked on 2008 by Tim Bird
#
import sys, os
def usage():
print("""Usage: diffconfig [-h] [-m] [<config1> <config2>]
Diffconfig is a simple utility for comparing two .config files.
Using standard diff to compare .config files often includes extraneous and
distracting information. This utility produces sorted output with only the
changes in configuration values between the two files.
Added and removed items are shown with a leading plus or minus, respectively.
Changed items show the old and new values on a single line.
If -m is specified, then output will be in "merge" style, which has the
changed and new values in kernel config option format.
If no config files are specified, .config and .config.old are used.
Example usage:
$ diffconfig .config config-with-some-changes
-EXT2_FS_XATTR n
CRAMFS n -> y
EXT2_FS y -> n
LOG_BUF_SHIFT 14 -> 16
PRINTK_TIME n -> y
""")
sys.exit(0)
# returns a dictionary of name/value pairs for config items in the file
def readconfig(config_file):
d = {}
for line in config_file:
line = line[:-1]
if line[:7] == "CONFIG_":
name, val = line[7:].split("=", 1)
d[name] = val
if line[-11:] == " is not set":
d[line[9:-11]] = "n"
return d
def print_config(op, config, value, new_value):
global merge_style
if merge_style:
if new_value:
if new_value=="n":
print("# CONFIG_%s is not set" % config)
else:
print("CONFIG_%s=%s" % (config, new_value))
else:
if op=="-":
print("-%s %s" % (config, value))
elif op=="+":
print("+%s %s" % (config, new_value))
else:
print(" %s %s -> %s" % (config, value, new_value))
def main():
global merge_style
# parse command line args
if ("-h" in sys.argv or "--help" in sys.argv):
usage()
merge_style = 0
if "-m" in sys.argv:
merge_style = 1
sys.argv.remove("-m")
argc = len(sys.argv)
if not (argc==1 or argc == 3):
print("Error: incorrect number of arguments or unrecognized option")
usage()
if argc == 1:
# if no filenames given, assume .config and .config.old
build_dir=""
if "KBUILD_OUTPUT" in os.environ:
build_dir = os.environ["KBUILD_OUTPUT"]+"/"
configa_filename = build_dir + ".config.old"
configb_filename = build_dir + ".config"
else:
configa_filename = sys.argv[1]
configb_filename = sys.argv[2]
try:
a = readconfig(open(configa_filename))
b = readconfig(open(configb_filename))
except (IOError):
e = sys.exc_info()[1]
print("I/O error[%s]: %s\n" % (e.args[0],e.args[1]))
usage()
# print items in a but not b (accumulate, sort and print)
old = []
for config in a:
if config not in b:
old.append(config)
old.sort()
for config in old:
print_config("-", config, a[config], None)
del a[config]
# print items that changed (accumulate, sort, and print)
changed = []
for config in a:
if a[config] != b[config]:
changed.append(config)
else:
del b[config]
changed.sort()
for config in changed:
print_config("->", config, a[config], b[config])
del b[config]
# now print items in b but not in a
# (items from b that were in a were removed above)
new = sorted(b.keys())
for config in new:
print_config("+", config, None, b[config])
main()
![swh spinner](/static/img/swh-spinner.gif)
Computing file changes ...