Setting up the pty in the master constructor ends up creating a new pty
on every stat(2) call on /dev/ptmx. Only do this when actually opening
the device, not when using the device class in another, non-opening
context.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Both flags are outdated and collide with official flags in
sys/_default_fcntl.h, which may result in weird misbehaviour
of file functions.
O_NOSYMLINK is not used anyway.
O_DIROPEN is used in fhandler_virtual and derived classes.
The collision with O_NOFOLLOW results in spurious EISDIR
errors when, e. g., reading files in the registry.
fhandler_base::open_fs uses O_DIROPEN in the call to
fhandler_base::open, but it's not used in this context
further down the road.
Drop both flags and create an alternative "diropen" bool
flag in fhandler_virtual.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
This is necessary in order to be consistent with the following comment
in the definition of _Unwind_RaiseException() in the GCC source file
libgcc/unwind-seh.c:
The exception handler installed in crt0 will continue any GCC
exception that reaches there (and isn't marked non-continuable).
Previously we failed to do this and, as a consequence, the C++ runtime
didn't call std::terminate after an unhandled exception.
This fixes the problem reported here:
https://cygwin.com/pipermail/cygwin/2019-October/242795.htmlhttps://sourceware.org/pipermail/cygwin/2020-August/245897.html
If the acl_t struct was at or above 0x80000000 then the pointer was
sign-extended to 0xffff_ffff_8000_0000 and so the index was lost.
Signed-off-by: David Allsopp <david.allsopp@metastack.com>
sys_mbstowcs is called with the destination buffer length
set to MaximumLength from the receiving UNICODE_STRING buffer.
This is twice as much as the actual size of the buffer in
wchar_t units, which is the unit expected by sys_mbstowcs.
sys_mbstowcs always attaches a NUL, within the destination
buffersize given. But if the string is exactly one wchar_t
less than the actual buffer, and the buffersize is given too
large, sys_mbstowcs writes a NUL one wchar_t beyond the buffer.
This has only been exposed with Cygwin 3.1.5 because alloca
on newer gcc 9 apparently allocates more tightly. The alloca
buffer here is requested with 16 bytes, which is exactly the
number of bytes required for the string L"cmd.exe". Older gcc
apparently allocated a few more bytes on the stack, while gcc 9
allocates in 16 byte granularity...
Fix this by giving the correct destination buffer size to
sys_mbstowcs.
Fixes: https://cygwin.com/pipermail/cygwin/2020-June/245226.html
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
This partially reverts commit
f36262d56a. That commit incorrectly
made the st_mode of a fifo reflect the Windows permissions of the disk
file underlying the fifo.
WSL symlinks are reparse points containing a POSIX path in UTF-8.
On filesystems supporting reparse points, use this symlink type.
On other filesystems, or in case of error, fall back to the good
old plain SYSTEM file.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Treat WSL symlinks just like other symlinks. Convert
absolute paths pointing to Windows drives via
/mnt/<driveletter> to Windows-style paths <driveletter>:
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
So far ioctl(TIOCINQ) could end up returning -1 with errno set to EINVAL
if a non-zero device error mask has been returned by ClearCommError.
This doesn't reflect Linux behaviour, which always returns the number of
chars in the inbound queue, independent of any I/O error condition.
EINVAL was a pretty weird error code to use in this scenario, too.
Fix this by dropping all checking for device errors in the TIOCINQ
case. Just return the number of chars in the inbound queue.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
- Accessing shared_console_info before initialization causes access
violation because it is a NULL pointer. The cause of the problem
reported in https://cygwin.com/ml/cygwin/2020-02/msg00197.html is
this NULL pointer access in request_xterm_mode_output() when it is
called from close(). This patch makes sure that shared_console_info
is not NULL before calling request_xterm_mode_output().
NSIG is a deprecated symbol only visible under MISC visibility.
_NSIG is used widely instead, and on most systems NSIG is
defined in terms of _NSIG.
Follow suit: Change NSIG to _NSIG throughout and change visiblity
of NSIG to be defined only in __MISC_VISIBLE case.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Commit 283cb372, "Cygwin: normalize_win32_path: improve error
checking", required a prefix '\\?\' or '\??\' in the source path to be
followed by 'UNC\' or 'X:\', where X is a drive letter. That was too
restrictive, since it disallowed the paths '\\?\X: and '\??\X:'. This
caused problems when a user tried to use the root of a drive as the
Cygwin installation root, as reported here:
https://cygwin.com/ml/cygwin/2020-01/msg00111.html
Modify the requirement so that '\??\X:' and '\\?\X:' are now allowed
as source paths, without a trailing backslash.
Though our implementation of cpu sets doesn't need it, software from
Linux environments expects this definition to be present. It's
documented on the Linux CPU_SET(3) man page but was left out due to
oversight.
Addresses https://cygwin.com/ml/cygwin/2019-12/msg00248.html
Commit 5a0f2c00aa "Cygwin: fork/exec: fix child process permissions"
removed the PROCESS_DUP_HANDLE handle permission of the parent process
handle in the child to avoid a security problem.
It turned out that this broke the following scenario: If a process forks
and then the parent execs, the child loses the ability to register the
parent's death. To wit, after the parent died the child process does
not set its own PPID to 1 anymore.
The current exec mechanism copies required handle values (handles to
keep contact to the child processes) into the child_info for the
about-to-be-exec'ed process. The exec'ed process is supposed to
duplicate these handles. This fails, given that we don't allow the
exec'ed process PROCESS_DUP_HANDLE access to the exec'ing process since
commit 5a0f2c00aa.
The fix is to avoid the DuplicateHandle calls in the exec'ed process.
This patch sets the affected handles to "inheritable" in the exec'ing
process at exec time. The exec'ed process just copies the handle values
and resets handle inheritance to "non-inheritable". The exec'ing
process doesn't have to reset handle inheritance, it exits after setting
up the exec'ed process anyway.
Testcase: $ ssh-agent /bin/sleep 3
ssh-agent forks and the parent exec's sleep. After sleep exits, `ps'
should show ssh-agent to have PPID 1, and eventually ssh-agent exits.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Call find_exec with the FE_NNF flag to enforce a NULL return when the
executable isn't found in $PATH. Convert NULL to "". This aligns
spawnvp and spawnvpe with execvp and execvpe.
If the directory name has the form 'x:' followed by one or more
slashes or backslashes, and if there's at least one backslash, assume
that the user is referring to 'x:\', the root directory of drive x,
and don't strip the backslash.
Previously all trailing slashes and backslashes were stripped, and the
name was treated as a relative file name containing a literal colon.
Addresses https://cygwin.com/ml/cygwin/2019-08/msg00334.html.
On sigwaitinfo or reading from a signalfd, signal processing sets up
signal handling via sigdelayed even if the handler address is NULL.
This doesn't have any impact on sigwaitinfo scenarios (or at least, I
wasn't able to come up with a reproducer) but it breaks signalfd
scenarios, where eventually a call to call_signal_handler from
sigdelayed will try to call the NULL function.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Corinna Vinschen
Ken Brown
David Allsopp
Takashi Yano
Mark Geisert