[GIT PULL 06/19 for v7.4] vfs binfmt

[Christian Brauner]

Hey Linus,

/* Summary */

This only lets punctuation delimit a binfmt_misc register string.
Arbitrary delimiters never made sense and nothing uses them. Every new
flag shrank the set of possible delimiters and made extensions more
hazardous than they need to be. Letters, digits, whitespace, control
characters, bytes above 0x7f and the backslash now get EINVAL.
Everything deployed uses ':' anyway. This extends the fix that rejected
a flag character as the delimiter. Selftests and documentation are
included.

/* Testing */

No build failures or warnings were observed.

/* Conflicts */

Merge conflicts with mainline
=============================

No known conflicts.

Merge conflicts with other trees
================================

No known conflicts.

The following changes since commit cee9395acd8043be0644b25c34bfa86623f2b935:

  Linux 7.3-rc1 (2026-08-30 13:34:40 -0700)

are available in the Git repository at:

  git@xxxxxxxxxxxxxxxxxxx:pub/scm/linux/kernel/git/vfs/vfs tags/vfs-7.4-rc1.binfmt

for you to fetch changes up to 87b76786cc04c8137133a360088d94ab2ed592ca:

  Merge patch series "binfmt_misc: only let punctuation delimit a register string" (2026-08-31 10:06:36 +0200)

----------------------------------------------------------------
vfs-7.4-rc1.binfmt

Please consider pulling these changes from the signed vfs-7.4-rc1.binfmt tag.

Thanks!
Christian

----------------------------------------------------------------
Christian Brauner (4):
      binfmt_misc: only let punctuation delimit a register string
      selftests/exec: test delimiter restrictions
      binfmt_misc: document the field delimiter
      Merge patch series "binfmt_misc: only let punctuation delimit a register string"

 Documentation/admin-guide/binfmt-misc.rst        |   3 +
 fs/binfmt_misc.c                                 |  12 ++-
 tools/testing/selftests/exec/Makefile            |   4 +
 tools/testing/selftests/exec/binfmt_misc_delim.c | 127 +++++++++++++++++++++++
 4 files changed, 143 insertions(+), 3 deletions(-)
 create mode 100644 tools/testing/selftests/exec/binfmt_misc_delim.c