Before commit 44f73c5a62 ("Cygwin: Fix segfalt when too many command
line args are specified.") we had no actual argument size limit, except
for the fact that the child process created another copy of the argv
array on the stack, which could result in a stack overflow and a
subsequent SEGV. Commit 44f73c5a62 changed that by allocating the
additional argv array via malloc, and it introduced a new SC_ARG_MAX
limit along the lines of the typical Linux limit.
However, this new limit is artificial. Cygwin allocates all argument
and environment data on the cygheap. We only run out of ARG_MAX space
if we're out of memory resources.
Change argument size handling accordingly:
- Drop the args size check from child_info_spawn::worker.
- Return -1 from sysconf (SC_ARG_MAX), i. e., the argument size limit
is undefined.
- Change argv handling in class av, so that a failing cmalloc is not
fatal. This allows the parent process to return E2BIG if it's out
of cygheap resources.
- In the child, add a check around the new malloc call, so that it
doesn't result in a SEGV if the child process gets unexpectedly into
an ENOMEM situation at this point. In this (unlikely) case, proceed
with the original __argv array instead. Add comment to explain why.
Fixes: 44f73c5a62 ("Cygwin: Fix segfalt when too many command line args are specified.")
Tested-by: Takashi Yano <takashi.yano@nifty.ne.jp>
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Previously, the number of command line args was not checked for
cygwin process. Due to this, segmentation fault was caused if too
many command line args are specified.
https://cygwin.com/pipermail/cygwin/2023-August/254333.html
Since char *argv[argc + 1] is placed on the stack in dll_crt0_1(),
STATUS_STACK_OVERFLOW occurs if the stack does not have enough
space.
With this patch, char *argv[] is placed in heap instead of stack
and ARG_MAX is increased from 32000 to 2097152 which is default
value of Linux. The argument length is also compared with ARG_MAX
and spawnve() returns E2BIG if it is too long.
Reported-by: Ed Morton
Reviewed-by: Corinna Vinschen <corinna@vinschen.de>
Signed-off-by: Takashi Yano <takashi.yano@nifty.ne.jp>
After the commit fbfea31dd9, switch_to_nat_pipe is not cleared
properly when non-cygwin app is terminated in the case where the
pseudo console is disabled. This is because get_winpid_to_hand_over()
sometimes returns PID of cygwin process even though it should return
only PID of non-cygwin process. This patch fixes the issue by adding
a new argument which requests only PID of non-cygwin process to
get_console_process_id().
Fixes: fbfea31dd9 ("Cygwin: pty: Avoid cutting the branch the pty master is sitting on.")
Signed-off-by: Takashi Yano <takashi.yano@nifty.ne.jp>
Previously, though readahead buffer handling in pty master was not
fully thread-safe, accept_input() was called from peek_pipe() thread
in select.cc. This caused the problem reported in:
https://cygwin.com/pipermail/cygwin/2023-July/253984.html
The mechanism of the problem is:
1) accept_input() which is called from peek_pipe() thread calls
eat_readahead(-1) before reading readahead buffer. This allows
writing to the readahead buffer from another (main) thread.
2) The main thread calls fhandler_pty_master::write() just after
eat_readahead(-1) was called and before reading the readahead
buffer by accept_input() called from peek_pipe() thread. This
overwrites the readahead buffer.
3) The read result from readahead buffer which was overwritten is
sent to the slave.
This patch makes readahead buffer handling fully thread-safe using
input_mutex to resolve this issue.
Fixes: 7b03b0d8ce ("select.cc (peek_pipe): Call flush_to_slave whenever we're checking for a pty master.")
Reported-by: Thomas Wolff <towo@towo.net>
Signed-off-by: Takashi Yano <takashi.yano@nifty.ne.jp>
Add uchar.h accordingly.
For the c32 functions, use the internal functions wirtomb and mbrtowi
as base, and convert wirtomb and mbrtowi to inline functions calling
the c32 functions.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
While st_rdev returned by fstat() for /dev/tty should be FH_TTY,
the current cygwin1.dll returns FH_PTYS+minor or FH_CONS+minor.
Similarly, fstat() does not return correct value for /dev/console,
/dev/conout, /dev/conin or /dev/ptmx.
This patch fixes the issue by:
1) Introduce dev_referred_via in fhandler_termios.
2) Add new argument, which has dev_t value referred by open(),
for constructors of fhandler_pty_slave and fhandler_pty_master to
set the value of dev_referred_via.
3) Set st_rdev using dev_referred_via in fhandler_termios::fstat()
if it is available.
Reviewed-by: Corinna Vinschen <corinna@vinschen.de>
Signed-off-by: Takashi Yano <takashi.yano@nifty.ne.jp>
This solves redefinition of FILE_CS_FLAG_CASE_SENSITIVE_DIR in winnt.h
and fixes the following compiler errors
ntdll.h:523:3: error: expected identifier before numeric constant
523 | FILE_CS_FLAG_CASE_SENSITIVE_DIR = 0x01
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
ntdll.h:522:1: note: to match this ‘{’
522 | {
| ^
This patch hails from Git for Windows (where the Cygwin runtime is used
in the form of a slightly modified MSYS2 runtime), where it is a
well-established technique to let the `$HOME` variable define where the
current user's home directory is, falling back to `$HOMEDRIVE$HOMEPATH`
and `$USERPROFILE`.
The idea is that we want to share user-specific settings between
programs, whether they be Cygwin, MSYS2 or not. Unfortunately, we
cannot blindly activate the "db_home: windows" setting because in some
setups, the user's home directory is set to a hidden directory via an
UNC path (\\share\some\hidden\folder$) -- something many programs
cannot handle correctly, e.g. `cmd.exe` and other native Windows
applications that users want to employ as Git helpers.
The established technique is to allow setting the user's home directory
via the environment variables mentioned above: `$HOMEDRIVE$HOMEPATH` or
`$USERPROFILE`. This has the additional advantage that it is much
faster than querying the Windows user database.
Of course this scheme needs to be opt-in. For that reason, it needs
to be activated explicitly via `db_home: env` in `/etc/nsswitch.conf`.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Update the list of filesystem flags to the flags supported since
Windows 7. Make sure to use the new flags only with Windows
filesystems, not with 3rd party filesystems.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
This patch replaces ctty constants with more descriptive macros
(CTTY_UNINITIALIZED and CTTY_RELEASED) rather than -1 and -2 as
well as checking sign with CTTY_IS_VALID().
Fixes: 3b7df69aaa (Cygwin: ctty: Add comments for the special values: -1 and -2.)
Suggested-by: Corinna Vinschen <corinna@vinschen.de>
Signed-off-by: Takashi Yano <takashi.yano@nifty.ne.jp>
Deviation from standard: If the input is broken, the output will be
broken. I. e., we just copy the current byte over into the wint_t
destination and try to pick up on the next byte. This is in line
with the way fnmatch works.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Effectively revert commit 57bac33359. The fact that the
devanagari modifier was called devanagar (missing the trailing 'i')
is a result of `locale -av' shortening the locale name to a maximum
of 15 characters.
D'oh. I guess we need a better way to do this...
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Generate lc_def_codeset.h header containing the default mapping from
locale to codeset on Linux. Use this mapping in __set_charset_from_locale
in the first place.
For every locale not covered by this table, just map Windows codepages
to equivalent codesets used on Linux/Unix, getting rid of LCIDs entirely.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
g_Ctoc, converting the UTF-32 filenames to multibyte, still
used UTF-16 to multibyte conversion. Introduce a wirtomb
helper and fix that.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Allow the [.<sym>.] expression
This requires a string comparision rather than a character
comparison. Introduce and use __wscollate_range_cmp.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
lc_collelem.h: autogenerated table of collating element, taken
from glibc
is_unicode_coll_elem: Check if a UTF-32 string is a collating element
next_unicode_char: return length of prefix from a string constituting
a complete character in the current locale, taking
collating elements into acocunt.
wcintowcs: convert UTF-16 to UTF-32 string
wcilen: return number of characters in a UTF-32 string
wcincmp: compare two fixed-size UTF-32 strings
Used in followup patches introducing collating symbols
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=179721
After FreeBSD eventually picked up the bugreport from within
only 5 years, rename __collate_range_cmp to __wcollate_range_cmp
as suggested all along, and make it type safe (wint_t instead of
wchar_t for hopefully obvious reasons...)
While at it, drop __collate_load_error and fix the checks for
it in glob and fnmatch.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
is_unicode_equiv compares two UTF-32 values and returns 1 if
both are member of the same Unicode equivalence class, 0 otherwise.
Note that this function only works with precomposed characters
per Unicode normalization form C. It doesn't handle decomposed
characters, just like its counterpart in glibc. I.e., equivalence
class comparison using decomposed chars won't work. Example:
fnmatch("[=n=]", "ñ") == 0
fnmatch("[=ñ=]", "n") == 0
but
fnmatch("[=n=]", "n\x0303") == 1
fnmatch("[=n\x0303=]", "n") == 1
fnmatch("[=n\x0303=]", "n\x0303") == 1
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Given how UTF-16 isn't capable to hold all Unicode chars in a single
wchar_t, we need a function returning a wint_t value representing
a UTF-32 value for comparison functions. Fortunately the important
wide character functions like towupper/towlower, isw<class>, iswctype,
etc, already take wint_t values and newlib handles them as UTF-32.
If only we had switched wchar_t to 32 bit way back when... sigh.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Avoid the mistake fixed in the preceeding commit by passing
the mode_t argument by reference. This also affects a couple
other functions calling get_posix_access in turn.
Fixes: bc444e5aa4 ("Reapply POSIX ACL changes.")
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Previously, SNDCTL_DSP_SETFRAGMENT was just a fake. In this patch,
it has been implemented to allow latency control in some apps.
Reviewed-by: Corinna Vinschen <corinna@vinschen.de>
Signed-off-by: Takashi Yano <takashi.yano@nifty.ne.jp>
fhandler_dev_dsp (OSS) has a problem that waitforallsent(), which is
called from close(), falls into infinite loop if another thread calls
write() accidentally after close(). This patch fixes the issue.
Reviewed-by: Corinna Vinschen <corinna@vinschen.de>
Signed-off-by: Takashi Yano <takashi.yano@nifty.ne.jp>
Previously, fhandler_dev_dsp (OSS) has a problem that fcntl() does
not take effect at all. This patch fixes the issue.
Signed-off-by: Takashi Yano <takashi.yano@nifty.ne.jp>
Reviewed-by: Corinna Vinschen <corinna@vinschen.de>
With the previous commit 9ddd48ee1b ("Cygwin: /proc/<PID>/maps:
print real shared region addresses"), the real addresses of
the standard shared regions (cygwin, user, myself, shared console)
are read from the printed process itself. We don't need fixed
addresses anymore, so drop the definitions and simplify open_shared.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
So far, the addresses printed for the shared regions of a process
were faked. The assumption was that the shared regions are always
in the same place in all processes, so we just printed the addresses
of the current process. This is no safe bet. The only safe bet is
the address of the cygheap. So keep track of the addresses in the
cygheap and read the addresses from the cygheap of the observed
processes. Add output for the shared console.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Fix comments accordingly.
This is in preparation for a change in open_shared, handling shared
regions more cleanly.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
For ages, open_shared uses the shared_locations parameter as
output to indicate if the mapping for a shared region has been
created or just opened. Split this into two parameters. Use
the shared_locations parameter as input only, return the creation
state of the mapping in a bool reference parameter.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
So far the capability bits were stored in the .cygwin_dll_common
R/W section because we overwrite the is_server bit. Just don't.
Move the bit to class wincapc instead and define all wincaps
bitfields const.
Fixes: 8937c103ed ("* wincap.cc (all wincaps): Store in .cygwin_dll_common section same as wincap. Add comment to explain why.")
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Previously, the console device could not be accessed from other terminals.
Due to this limitation, GNU screen and tmux cannot be opened in console.
With this patch, console device can be accessed from other TTYs, such as
other consoles or ptys. Thanks to this patch, screen and tmux get working
in console.
Reviewed-by: Corinna Vinschen <corinna@vinschen.de>
Signed-off-by: Takashi Yano <takashi.yano@nifty.ne.jp>
Only required for Windows 7.
This in turn allows to drop the helper_pid and related
methods from fhandler_pty_common.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Only required for Windows 7.
This allows to remove fhandler_pipe::get_query_hdl_per_system(),
too.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Takashi Yano
Corinna Vinschen
Brian Inglis
Biswapriyo Nath
Johannes Schindelin