204151 - A process created by PR_CreateProcess with an inherited fd can't pass any inheritable fd to a child process created by PR_CreateProcess.

Status: RESOLVED FIXED

(NSPR :: NSPR, defect)

Description

[Wan-Teh Chang]

If a process was itself created by PR_CreateProcess with
an inherited fd, it won't be able to pass any inheritable
fd's to a child process created by PR_CreateProcess.

NSPR passes the values of inheritable fd's in a magic
environment variable in the child process's environment.
If a process was itself created by PR_CreateProcess, it
will have that magic environment variable in its environment.
If this process calls PR_CreateProcess with an inheritable
fd, it will append the magic environment variable to the
current environment, without checking if the magic environment
variable already exists.  So the child's environment array
ends up with two entries of that magic environment variable,
with the wrong one appearing before the right one.  When the
child process gets its inherited fd, it gets the wrong value.

Comment 1

[Wan-Teh Chang]

Attachment: Proposed patch

Search for existing NSPR_INHERIT_FDS environment variable
in the environment.  If it exists, replace it with the new
value rather than appending the new value to the environment.

Comment 2

[Wan-Teh Chang]

Attachment: Proposed patch v1.1

The previous patch has a bug in the Windows code.
The second argument to qsort() may be incorrect.

Comment 3

[Simon Fraser [no longer active]]

Do we still need this?

Comment 4

[Wan-Teh Chang]

Yes, we should still fix this bug even though the
affected customer has implemented a workaround.

Comment 5

[Kai Engert [:KaiE:]]

is this ready for check in?

Comment 6

[Wan-Teh Chang]

I checked in the patch on the NSPR trunk for NSPR 4.7.

Checking in beos/bproc.c;
/cvsroot/mozilla/nsprpub/pr/src/md/beos/bproc.c,v  <--  bproc.c
new revision: 3.7; previous revision: 3.6
done
Checking in unix/uxproces.c;
/cvsroot/mozilla/nsprpub/pr/src/md/unix/uxproces.c,v  <--  uxproces.c
new revision: 3.21; previous revision: 3.20
done
Checking in windows/ntmisc.c;
/cvsroot/mozilla/nsprpub/pr/src/md/windows/ntmisc.c,v  <--  ntmisc.c
new revision: 3.23; previous revision: 3.22
done