diff options
author | Vasily Averin <vvs@sw.ru> | 2006-10-11 04:21:50 -0400 |
---|---|---|
committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-10-11 14:14:21 -0400 |
commit | 5a2b4062f5adf2218b9b021e1c33f374bf142cb2 (patch) | |
tree | bbcfec5a14d55423a5632963cdfcf2b689be5222 | |
parent | 2245d7c21f5bb1f104ee1226ebcb3dd5b9acfff6 (diff) |
[PATCH] ext2: errors behaviour fix
Current error behaviour for ext2 and ext3 filesystems does not fully
correspond to the documentation and should be fixed.
According to man 8 mount, ext2 and ext3 file systems allow to set one of 3
different on-errors behaviours:
---- start of quote man 8 mount ----
errors=continue / errors=remount-ro / errors=panic
Define the behaviour when an error is encountered. (Either ignore
errors and just mark the file system erroneous and continue, or remount
the file system read-only, or panic and halt the system.) The default is
set in the filesystem superblock, and can be changed using tune2fs(8).
---- end of quote ----
However EXT3_ERRORS_CONTINUE is not read from the superblock, and thus
ERRORS_CONT is not saved on the sbi->s_mount_opt. It leads to the incorrect
handle of errors on ext3.
Then we've checked corresponding code in ext2 and discovered that it is buggy
as well:
- EXT2_ERRORS_CONTINUE is not read from the superblock (the same);
- parse_option() does not clean the alternative values and thus something
like (ERRORS_CONT|ERRORS_RO) can be set;
- if options are omitted, parse_option() does not set any of these options.
Therefore it is possible to set any combination of these options on the ext2:
- none of them may be set: EXT2_ERRORS_CONTINUE on superblock / empty mount
options;
- any of them may be set using mount options;
- 2 any options may be set: by using EXT2_ERRORS_RO/EXT2_ERRORS_PANIC on the
superblock and other value in mount options;
- and finally all three options may be set by adding third option in remount.
Currently ext2 uses these values only in ext2_error() and it is not leading to
any noticeable troubles. However somebody may be discouraged when he will try
to workaround EXT2_ERRORS_PANIC on the superblock by using errors=continue in
mount options.
This patch:
EXT2_ERRORS_CONTINUE should be read from the superblock as default value for
error behaviour. parse_option() should clean the alternative options and
should not change default value taken from the superblock.
Signed-off-by: Vasily Averin <vvs@sw.ru>
Acked-by: Kirill Korotaev <dev@openvz.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
-rw-r--r-- | fs/ext2/super.c | 16 |
1 files changed, 11 insertions, 5 deletions
diff --git a/fs/ext2/super.c b/fs/ext2/super.c index 513cd421ac0b..d8b9abd95d07 100644 --- a/fs/ext2/super.c +++ b/fs/ext2/super.c | |||
@@ -364,7 +364,6 @@ static int parse_options (char * options, | |||
364 | { | 364 | { |
365 | char * p; | 365 | char * p; |
366 | substring_t args[MAX_OPT_ARGS]; | 366 | substring_t args[MAX_OPT_ARGS]; |
367 | unsigned long kind = EXT2_MOUNT_ERRORS_CONT; | ||
368 | int option; | 367 | int option; |
369 | 368 | ||
370 | if (!options) | 369 | if (!options) |
@@ -404,13 +403,19 @@ static int parse_options (char * options, | |||
404 | /* *sb_block = match_int(&args[0]); */ | 403 | /* *sb_block = match_int(&args[0]); */ |
405 | break; | 404 | break; |
406 | case Opt_err_panic: | 405 | case Opt_err_panic: |
407 | kind = EXT2_MOUNT_ERRORS_PANIC; | 406 | clear_opt (sbi->s_mount_opt, ERRORS_CONT); |
407 | clear_opt (sbi->s_mount_opt, ERRORS_RO); | ||
408 | set_opt (sbi->s_mount_opt, ERRORS_PANIC); | ||
408 | break; | 409 | break; |
409 | case Opt_err_ro: | 410 | case Opt_err_ro: |
410 | kind = EXT2_MOUNT_ERRORS_RO; | 411 | clear_opt (sbi->s_mount_opt, ERRORS_CONT); |
412 | clear_opt (sbi->s_mount_opt, ERRORS_PANIC); | ||
413 | set_opt (sbi->s_mount_opt, ERRORS_RO); | ||
411 | break; | 414 | break; |
412 | case Opt_err_cont: | 415 | case Opt_err_cont: |
413 | kind = EXT2_MOUNT_ERRORS_CONT; | 416 | clear_opt (sbi->s_mount_opt, ERRORS_RO); |
417 | clear_opt (sbi->s_mount_opt, ERRORS_PANIC); | ||
418 | set_opt (sbi->s_mount_opt, ERRORS_CONT); | ||
414 | break; | 419 | break; |
415 | case Opt_nouid32: | 420 | case Opt_nouid32: |
416 | set_opt (sbi->s_mount_opt, NO_UID32); | 421 | set_opt (sbi->s_mount_opt, NO_UID32); |
@@ -489,7 +494,6 @@ static int parse_options (char * options, | |||
489 | return 0; | 494 | return 0; |
490 | } | 495 | } |
491 | } | 496 | } |
492 | sbi->s_mount_opt |= kind; | ||
493 | return 1; | 497 | return 1; |
494 | } | 498 | } |
495 | 499 | ||
@@ -715,6 +719,8 @@ static int ext2_fill_super(struct super_block *sb, void *data, int silent) | |||
715 | set_opt(sbi->s_mount_opt, ERRORS_PANIC); | 719 | set_opt(sbi->s_mount_opt, ERRORS_PANIC); |
716 | else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_RO) | 720 | else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_RO) |
717 | set_opt(sbi->s_mount_opt, ERRORS_RO); | 721 | set_opt(sbi->s_mount_opt, ERRORS_RO); |
722 | else | ||
723 | set_opt(sbi->s_mount_opt, ERRORS_CONT); | ||
718 | 724 | ||
719 | sbi->s_resuid = le16_to_cpu(es->s_def_resuid); | 725 | sbi->s_resuid = le16_to_cpu(es->s_def_resuid); |
720 | sbi->s_resgid = le16_to_cpu(es->s_def_resgid); | 726 | sbi->s_resgid = le16_to_cpu(es->s_def_resgid); |