Without this patch, BusyBox handles bash pattern substitutions without
a terminating '/' character incorrectly.
Consider the following shell script:
_bootstrapver=5.0.211-r0
_referencesdir="/usr/${_bootstrapver/-*}/Sources"
echo $_referencesdir
This should output `/usr/5.0.211/Sources`. However, without this patch
it instead outputs `/usr/5.0.211Sources`. This is due to the fact that
BusyBox expects the bash pattern substitutions to always be terminated
with a '/' (at least in this part of subvareval) and thus reads passed
the substitution itself and consumes the '/' character which is part of
the literal string. If there is no '/' after the substitution then
BusyBox might perform an out-of-bounds read under certain circumstances.
When replacing the bash pattern substitution with `${_bootstrapver/-*/}`,
or with this patch applied, ash outputs the correct value.
Signed-off-by: Sören Tempel <soeren@soeren-tempel.net>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This significantly syncronises ash-signals and hush-signals tests.
function old new delta
process_wait_result 449 450 +1
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
With bash's read builtin it is possible to read from a file (e.g.
device-tree) until the first '\0' character:
IFS= read -r -d '' VARIABLE < file
In busybox ash the -d extension is also implemented, but checking the
read character for '\0' has to be performed after comparing with the
delimiter.
Signed-off-by: Christian Eggers <ceggers@arri.de>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream commit:
Date: Fri, 1 Jun 2018 18:25:29 +0800
expand: Ensure result is escaped in cvtnum
The minus sign generated from arithmetic expansion is currently
unquoted which causes anomalies when the result is used in where
the quoting matters.
This patch fixes it by explicitly calling memtodest on the result
in cvtnum.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream commit:
Date: Mon, 29 Apr 2019 19:13:37 +0500
expand: Fix trailing newlines processing in backquote expanding
According to POSIX.1-2008 we should remove newlines only at the end of
the substitution. Newlines-only substitions causes dash to remove
newlines before beggining of the substitution. The following code:
cat <<END
1
$(echo "")
2
END
prints "1<newline>2" instead of expected "1<newline><newline>2".
This patch fixes trailing newlines processing in backquote expanding.
Signed-off-by: Nikolai Merinov <n.merinov@inango-systems.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream commit:
Date: Mon, 27 May 2019 13:39:37 +0800
parser: Only accept single-digit parameter expansion outside of braces
This patch should fix the problem.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream commit:
Date: Wed, 28 Mar 2018 18:37:51 +0800
expand: Do not quote backslashes in unquoted parameter expansion
Here is a better example:
a="/*/\nullx" b="/*/\null"; printf "%s\n" $a $b
dash currently prints
/*/\nullx
/*/\null
bash prints
/*/\nullx
/dev/null
You may argue the bash behaviour is inconsistent but it actually
makes sense. What happens is that quote removal only applies to
the original token as seen by the shell. It is never applied to
the result of parameter expansion.
Now you may ask why on earth does the second line say "/dev/null"
instead of "/dev/\null". Well that's because it is not the quote
removal step that removed the backslash, but the pathname expansion.
The fact that the /de\v does not become /dev even though it exists
is just the result of the optimisation to avoid unnecessarily
calling stat(2). I have checked POSIX and I don't see anything
that forbids this behaviour.
So going back to dash yes I think we should adopt the bash behaviour
for pathname expansion and keep the existing case semantics.
This patch does exactly that. Note that this patch does not work
unless you have already applied
https://patchwork.kernel.org/patch/10306507/
because otherwise the optimisation mentioned above does not get
detected correctly and we will end up doing quote removal twice.
This patch also updates expmeta to handle naked backslashes at
the end of the pattern which is now possible.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
function old new delta
expmeta 618 653 +35
memtodest 146 147 +1
Tested to work with both ASH_INTERNAL_GLOB on and off.
hush does not handle this correctly.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream commit:
Date: Fri, 23 Mar 2018 18:58:47 +0800
expand: Fix ghost fields with unquoted $@/$*
You're right. The proper fix to this is to ensure that nulonly
is not set in varvalue for $*. It should only be set for $@ when
it's inside double quotes.
In fact there is another bug while we're playing with $@/$*.
When IFS is set to a non-whitespace character such as :, $*
outside quotes won't remove empty fields as it should.
This patch fixes both problems.
Reported-by: Martijn Dekker <martijn@inlv.org>
Suggested-by: Harald van Dijk <harald@gigawatt.nl>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
function old new delta
argstr 1111 1113 +2
evalvar 571 569 -2
varvalue 579 576 -3
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/2 up/down: 2/-5) Total: -3 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream commit:
Date: Wed, 4 Apr 2018 17:54:01 +0800
eval: Variable assignments on functions are no longer persistent
Dirk Fieldhouse <fieldhouse@gmx.net> wrote:
> In POSIX.1-2017 ("simultaneously IEEE Std 1003.1™-2017 and The Open
> Group Technical Standard Base Specifications, Issue 7")
> <http://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#tag_18_09>,
> we read under '2.9.1 Simple Commands'
>
> "Variable assignments shall be performed as follows:
> ...
> - If the command name is a standard utility implemented as a function
> (see XBD Utility), the effect of variable assignments shall be as if the
> utility was not implemented as a function.
> ...
> - If the command name is a function that is not a standard utility
> implemented as a function, variable assignments shall affect the current
> execution environment during the execution of the function. It is
> unspecified:
>
> * Whether or not the variable assignments persist after the
> completion of the function
>
> * Whether or not the variables gain the export attribute during
> the execution of the function
>
> * Whether or not export attributes gained as a result of the
> variable assignments persist after the completion of the function (if
> variable assignments persist after the completion of the function)"
POSIX used to require the current dash behaviour. However, you're
right that this is no longer the case.
This patch will remove the persistence of the variable assignment.
I have considered the exporting the variables during the function
execution but have decided against it because:
1) It makes the code bigger.
2) dash has never done this in the past.
3) You cannot use this portably anyway.
Reported-by: Dirk Fieldhouse <fieldhouse@gmx.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
function old new delta
evalcommand 1606 1635 +29
evalcase 313 317 +4
evalfun 280 268 -12
pushlocalvars 48 - -48
------------------------------------------------------------------------------
(add/remove: 0/1 grow/shrink: 2/1 up/down: 33/-60) Total: -27 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This necessitates switch from libc FILE api to a simple
homegrown replacement.
The change which fixes the bug here is the deleting of
restore_redirected_FILEs();
line. It was prematurely moving (restoring) script fd#3.
The fix is: we don't even _want_ to restore scrit fds,
we are perfectly fine with them being moved.
The only reason we tried to restore them is that FILE api
did not allow moving of FILE->fd.
function old new delta
refill_HFILE_and_getc - 93 +93
hfopen - 90 +90
hfclose - 66 +66
pseudo_exec_argv 591 597 +6
hush_main 1089 1095 +6
builtin_source 209 214 +5
save_fd_on_redirect 197 200 +3
setup_redirects 320 321 +1
fgetc_interactive 235 236 +1
i_peek_and_eat_bkslash_nl 99 97 -2
expand_vars_to_list 1103 1100 -3
restore_redirects 99 52 -47
fclose_and_forget 57 - -57
remember_FILE 63 - -63
------------------------------------------------------------------------------
(add/remove: 3/2 grow/shrink: 6/3 up/down: 271/-172) Total: 99 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This wasn't an ash bug in dollar_altvalue9, it was hush bug (and bash!)
function old new delta
expand_one_var 2236 2254 +18
expand_vars_to_list 1097 1103 +6
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/0 up/down: 24/0) Total: 24 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
ash might be a bit buggy, need to investigate dollar_altvalue9 test
function old new delta
expand_one_var 1639 2236 +597
expand_variables 112 128 +16
expand_vars_to_list 1117 1097 -20
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/1 up/down: 613/-20) Total: 593 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
