If job control is not enabled, background commands shall ignore SIGINT and
SIGQUIT, and it shall be possible to override that ignore in the same shell.
MFC after: 1 week
Austin Group bugs #1226 and #1250 changed the requirements for shell scripts
without #! (POSIX does not specify #!; this is about the shell execution
when execve(2) returns an [ENOEXEC] error).
POSIX says we shall allow execution if the initial part intended to be
parsed by the shell consists of characters and does not contain the NUL
character. This allows concatenating a shell script (ending with exec or
exit) and a binary payload.
In order to reject common binary files such as PNG images, check that there
is a lowercase letter or expansion before the last newline before the NUL
character, in addition to the check for the newline character suggested by
POSIX.
The shell maintains a count of the number of times SIGINT processing has
been disabled via INTOFF, so SIGINT processing resumes when all disables
have enabled again (INTON).
If an error occurs in a vfork() child, the processing of the error enables
SIGINT processing again, and the INTON in vforkexecshell() causes the count
to become negative.
As a result, a later INTOFF may not actually disable SIGINT processing. This
might cause memory corruption if a SIGINT arrives at an inopportune time. As
of r360452, it causes the shell to abort when it would unsafely allocate or
free memory in certain ways.
Note that various places such as errors in non-special builtins
unconditionally reset the count to 0, so the problem might still not always
be visible.
PR: 246497
Reported by: jbeich
MFC after: 2 weeks
If executing a file fails with an [ENOEXEC] error, the shell executes the
file as a shell script, except that this execution may instead result in an
error message if the file is binary.
Per a recent Austin Group interpretation, we will need to change this to
allow a concatenation of a shell script and a binary payload. See
Austin Group bugs #1226 and #1250.
MFC after: 1 week
The pipefail option allows checking the exit status of all commands in a
pipeline more easily, at a limited cost of complexity in sh itself. It works
similarly to the option in bash, ksh93 and mksh.
Like ksh93 and unlike bash and mksh, the state of the option is saved when a
pipeline is started. Therefore, even in the case of commands like
A | B &
a later change of the option does not change the exit status, the same way
(A | B) &
works.
Since SIGPIPE is not handled specially, more work in the script is required
for a proper exit status for pipelines containing commands such as head that
may terminate successfully without reading all input. This can be something
like
(
cmd1
r=$?
if [ "$r" -gt 128 ] && [ "$(kill -l "$r")" = PIPE ]; then
exit 0
else
exit "$r"
fi
) | head
PR: 224270
Relnotes: yes
SVN r342880 was designed to fix $((-9223372036854775808)) and things like
$((0x8000000000000000)) but also broke error detection for values of
variables without dollar sign ($((x))).
For compatibility, overflow in plain literals continues to be ignored and
the value is clamped to the boundary (except 9223372036854775808 which is
changed to -9223372036854775808).
Reviewed by: se (although he would like error checking to be removed)
MFC after: 2 weeks
X-MFC-with: r342880
Differential Revision: https://reviews.freebsd.org/D18926
results between an expression that refers to a variable by name and the
same expression that includes the same variable by value.
Submitted by: se@
MFC after: 1 week
If word in ${param?word} is missing, the shell shall write a default error
message. So expanding ${param?} when param is not set should write an error
message like
sh: param: parameter not set
This was broken by r316417.
PR: 233585
POSIX requires accepting unquoted newlines in word in parameter expansions
like ${param+word}, ${param#word}, although the Bourne shell did not support
it, it is not commonly used and might make it harder to find a missing
closing brace.
It was also strange that something like
foo="${bar#
}"
was rejected.
Reported by: Martijn Dekker via Robert Elz
If CDPATH is used non-trivially or the operand is "-", cd writes the
directory actually switched to. (We currently do this only in interactive
shells, but POSIX requires this in non-interactive shells as well.)
As mentioned in Austin group bug #1045, cd shall not return an error while
leaving the current directory changed. Therefore, ignore any write error.
It does not make much sense to generate the '-' in a pattern bracket
expression using arithmetic expansion, but it does not make sense to forbid
it either.
Try to avoid reprocessing the string if it is unnecessary.
It does not make much sense to generate the '-' in a pattern bracket
expression using arithmetic expansion, but it does not make sense to forbid
it either.
This test already passes.
The special case of modifying an existing alias does not work correctly if
the alias is currently in use. Instead, handle this case by unaliasing the
old alias (if any) and then creating a new alias.
The parsed internal representation of words consists of a byte string with a
list of nodes (commands in command substitution). Each unescaped CTLBACKQ or
CTLBACKQ | CTLQUOTE byte corresponds to an entry in the list.
If param in ${param#%##%%word} is not set, the word is not expanded (in a
deviation of POSIX shared with other ash variants and ksh93). Erroneously,
the pointer in the list of commands (argbackq) was not advanced. This caused
the wrong command to be executed later if the outer word contained another
command substitution.
Example:
echo "${unsetvar#$(echo a)}$(echo b)"
wrote "a" but should write "b".
MFC after: 1 week
Code like t=$(stat -f %m "$file") segfaulted if -T was active and a trap
was taken while the shell was waiting for the child process to finish.
What happened was that the dotrap() call in waitforjob() was hit. This
re-entered command execution (including expand.c) at a point not expected by
expbackq(), and global state (unallocated stack string and argbackq) was
corrupted.
To fix this, change expbackq() to prepare for command execution to be
re-entered.
Reported by: bdrewery
MFC after: 1 week
Per Austin group issue #884, always set IFS to $' \t\n'. As before, IFS will
be exported iff it was in the environment.
Most shells (e.g. bash, ksh93 and mksh) already did this. This change
improves predictability, in that scripts can simply rely on the default
value.
However, the effect on security is little, since applications should not be
calling the shell with attacker-controlled environment variable names in the
first place and other security-sensitive variables such as PATH should be
and are imported by the shell.
When using a new sh with an old (before 10.2) libc wordexp(), IFS is no
longer passed on. Otherwise, wordexp() continues to pass along IFS from the
environment per its documentation.
Discussed with: pfg
Relnotes: yes
Instead of changing the whole course to another POSIX-permitted way
for consistency and uniformity I decide to completely ignore missing
regex fucntionality and focus on fixing bugs in what we have now,
too many small obstacles we have choicing other way, counting ports.
Corresponding libc changes are backed out in r302824.
after r298107
Summary of changes:
- Replace all instances of FILES/TESTS with ${PACKAGE}FILES. This ensures that
namespacing is kept with FILES appropriately, and that this shouldn't need
to be repeated if the namespace changes -- only the definition of PACKAGE
needs to be changed
- Allow PACKAGE to be overridden by callers instead of forcing it to always be
`tests`. In the event we get to the point where things can be split up
enough in the base system, it would make more sense to group the tests
with the blocks they're a part of, e.g. byacc with byacc-tests, etc
- Remove PACKAGE definitions where possible, i.e. where FILES wasn't used
previously.
- Remove unnecessary TESTSPACKAGE definitions; this has been elided into
bsd.tests.mk
- Remove unnecessary BINDIRs used previously with ${PACKAGE}FILES;
${PACKAGE}FILESDIR is now automatically defined in bsd.test.mk.
- Fix installation of files under data/ subdirectories in lib/libc/tests/hash
and lib/libc/tests/net/getaddrinfo
- Remove unnecessary .include <bsd.own.mk>s (some opportunistic cleanup)
Document the proposed changes in share/examples/tests/tests/... via examples
so it's clear that ${PACKAGES}FILES is the suggested way forward in terms of
replacing FILES. share/mk/bsd.README didn't seem like the appropriate method
of communicating that info.
MFC after: never probably
X-MFC with: r298107
PR: 209114
Relnotes: yes
Tested with: buildworld, installworld, checkworld; buildworld, packageworld
Sponsored by: EMC / Isilon Storage Division
