Collin Funk <[email protected]> writes:
> Pádraig Brady <[email protected]> writes:
>
>> On 18/03/2026 06:09, Collin Funk wrote:
>>> I noticed that 'yes' did not use pipe2_safer to check that the file
>>> descriptors aren't any of the standard file descriptors. This fixes
>>> that and some similar cases in other programs.
>>> Is it worth a NEWS mention? I assume that it is difficult to reach a
>>> point where pipe or pipe2 would open a standard file descriptor in
>>> these areas, give that this hasn't been reported as a bug.
>>
>> Oh very good spot.
>>
>> I did check yes(1) with closed stdout,
>> with and without the initial probing write().
>> But it's best avoid these variances.
>>
>> I see we have sc_require_{stdio,stdlib}_safer in cfg.mk.
>> We probably should have a unistd variant also.
>
> This patch did add that. :)
>
> I pushed it. Thanks for the review.
Shouldn't the same go for fcntl--.h for open, openat, and creat?
Here is the proposed rule:
diff --git a/cfg.mk b/cfg.mk
index aa2c86e23..22d0d1f2d 100644
--- a/cfg.mk
+++ b/cfg.mk
@@ -579,6 +579,19 @@ sc_prohibit_short_facl_mode_spec:
halt='setfacl mode string length < 3; extend with hyphen(s)' \
$(_sc_search_regexp)
+# Ensure that "fcntl--.h" is used where appropriate.
+sc_require_fcntl_safer:
+ @if $(VC_LIST_EXCEPT) | grep -l '\.[ch]$$' > /dev/null; then \
+ files=$$(grep -El '$(begword)(open(at)?|creat) ?\(' \
+ $$($(VC_LIST_EXCEPT) \
+ | grep '\.[ch]$$')); \
+ test -n "$$files" && grep -LE 'include "fcntl--.h"' $$files \
+ | grep . && \
+ { echo '$(ME): the above files should use "fcntl--.h"' \
+ 1>&2; exit 1; } || :; \
+ else :; \
+ fi
+
# Ensure that "stdio--.h" is used where appropriate.
sc_require_stdio_safer:
@if $(VC_LIST_EXCEPT) | grep -l '\.[ch]$$' > /dev/null; then \
And the list of files it catches:
require_fcntl_safer
gl/lib/fd-reopen.c
gl/lib/targetdir.c
src/cat.c
src/chown-core.c
src/df.c
src/head.c
src/install.c
src/nohup.c
src/pinky.c
src/pr.c
src/selinux.c
src/sort.c
src/sync.c
src/system.h
src/tac.c
src/truncate.c
src/wc.c
src/who.c
maint.mk: the above files should use "fcntl--.h"
make: *** [cfg.mk:584: sc_require_fcntl_safer] Error 1
Collin
