From d0668a0df3000ab5b3cc501ba66bf0ef7757accb Mon Sep 17 00:00:00 2001
From: Paul Chaignon <paul.chaignon@gmail.com>
Date: Sun, 19 Nov 2023 18:59:32 +0100
Subject: sys/linux: use nested flag definitions where sensible

All flags that are subset of other flags were identified with the
following Bash script [1]. Only a small set of flags identified by the
script were rewritten to use nested flag definitions, after manually
checking if it makes sense (based on syzkaller context and man pages).

For example, msgget_flags was rewritten as follows:

    -msgget_flags = IPC_CREAT, IPC_EXCL, S_IRUSR, S_IWUSR, S_IXUSR, S_IRGRP, S_IWGRP, S_IXGRP, S_IROTH, S_IWOTH, S_IXOTH
    +msgget_flags = IPC_CREAT, IPC_EXCL, open_mode

According to the msgget(2) man page:

    Upon creation, the least significant bits of the argument msgflg
    define the permissions of the message queue.  These permission bits
    have the same format and semantics as the permissions specified for
    the mode argument of open(2).

So it is correct to use open_mode directly in the definition of the
flags for msgget(2).

1 -

    #!/bin/bash

    regexp_flags="^(\w+)\s*=\s+([a-zA-Z\"][^=]*)$"

    is_subset() {
      local -n subset=$1
      local -n superset=$2
      for element in "${subset[@]}"; do
        if [[ ! " ${superset[@]} " =~ " $element " ]]; then
          return 1
        fi
      done
      return 0
    }

    declare -A parsed_lines

    while IFS= read -r line; do
      if [[ ! "$line" =~ $regexp_flags ]]; then
        continue
      fi
      list_name="${BASH_REMATCH[1]}"
      values="${BASH_REMATCH[2]}"
      IFS=',' read -r -a values_array <<< "$(echo "$values" | sed 's/ //g' | tr ',' '\n' | sort | tr '\n' ',')"

      # Skip flags with too few value.
      if [ "${#values_array[@]}" -lt 3 ]; then
        continue
      fi
      # Skip the syz0, syz1, etc. lists.
      if [ "${values_array[0]}" = "\"syz0\"" ]; then
        continue
      fi
      parsed_lines["${list_name}"]="${values_array[@]}"
    done

    for list_name in "${!parsed_lines[@]}"; do
      values_array=(${parsed_lines["$list_name"]})
      for other_list_name in "${!parsed_lines[@]}"; do
        other_values_array=(${parsed_lines["$other_list_name"]})
        if [ "$list_name" = "$other_list_name" ]; then
          continue
        fi

        if is_subset values_array other_values_array; then
          if [ "${#values_array[@]}" -eq "${#other_values_array[@]}" ]; then
            echo "$list_name EQUALS $other_list_name"
          else
            echo "$list_name is a SUBET of $other_list_name"
          fi
        fi
      done
    done

Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com>
---
 sys/linux/fs_ioctl_btrfs.txt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'sys/linux/fs_ioctl_btrfs.txt')

diff --git a/sys/linux/fs_ioctl_btrfs.txt b/sys/linux/fs_ioctl_btrfs.txt
index 6f854f93a..f4133a8f2 100644
--- a/sys/linux/fs_ioctl_btrfs.txt
+++ b/sys/linux/fs_ioctl_btrfs.txt
@@ -445,6 +445,6 @@ btrfs_ioctl_get_dev_stats_flags = BTRFS_DEV_STATS_RESET
 btrfs_ioctl_quota_ctl_cmd = BTRFS_QUOTA_CTL_ENABLE, BTRFS_QUOTA_CTL_DISABLE, BTRFS_QUOTA_CTL_RESCAN__NOTUSED
 btrfs_ioctl_dev_replace_args_cmd = BTRFS_IOCTL_DEV_REPLACE_CMD_START, BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS, BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL, BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR, BTRFS_IOCTL_DEV_REPLACE_RESULT_NOT_STARTED, BTRFS_IOCTL_DEV_REPLACE_RESULT_ALREADY_STARTED, BTRFS_IOCTL_DEV_REPLACE_RESULT_SCRUB_INPROGRESS
 cont_reading_from_srcdev_mode_flags = BTRFS_IOCTL_DEV_REPLACE_CONT_READING_FROM_SRCDEV_MODE_ALWAYS, BTRFS_IOCTL_DEV_REPLACE_CONT_READING_FROM_SRCDEV_MODE_AVOID
-btrfs_ioctl_feature_compat_flags = BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE, BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE_VALID
+btrfs_ioctl_feature_compat_flags = btrfs_ioctl_feature_compat_ro_flags
 btrfs_ioctl_feature_compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE, BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE_VALID
 btrfs_ioctl_feature_incompat_flags = BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF, BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL, BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS, BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO, BTRFS_FEATURE_INCOMPAT_COMPRESS_ZSTD
-- 
cgit mrf-deployment