[PATCH] xfs_repair: Ensure just xfs_repair without -n can return a status code of 2

[PATCH] xfs_repair: Ensure just xfs_repair without -n can return a status code of 2

[Xiao Yang]

Since commit b04647edea32, xfs_repair -L could't succeed to clear a dirty log
and returned a status of 2.  Besides, xfs_repair -n returned a status of 2
instead of 1 if a dirty log was detected.  I think just xfs_repair without -n
should return a status code of 2 when getting a dirty log, so fix it.  We can
expose this issue by xfstests case xfs/098.

Fixes:'commit b04647edea32 ("xfs_repair: exit with status 2 if log dirtiness is unknown")'

Signed-off-by: Xiao Yang <yangx.jy@cn.fujitsu.com>
---
 repair/phase2.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/repair/phase2.c b/repair/phase2.c
index 992e997..c124882 100644
--- a/repair/phase2.c
+++ b/repair/phase2.c
@@ -78,12 +78,13 @@ zero_log(
 		do_warn(
 		_("zero_log: cannot find log head/tail (xlog_find_tail=%d)\n"),
 			error);
-		if (!no_modify && !zap_log)
+		if (!no_modify && !zap_log) {
 			do_warn(_(
 "ERROR: The log head and/or tail cannot be discovered. Attempt to mount the\n"
 "filesystem to replay the log or use the -L option to destroy the log and\n"
 "attempt a repair.\n"));
 			exit(2);
+		}
 	} else {
 		if (verbose) {
 			do_log(
-- 
1.8.3.1

Re: [PATCH] xfs_repair: Ensure just xfs_repair without -n can return a status code of 2

[Eric Sandeen]

On 2/26/18 11:50 PM, Xiao Yang wrote:
> Since commit b04647edea32, xfs_repair -L could't succeed to clear a dirty log
> and returned a status of 2.  Besides, xfs_repair -n returned a status of 2
> instead of 1 if a dirty log was detected.  I think just xfs_repair without -n
> should return a status code of 2 when getting a dirty log, so fix it.  We can
> expose this issue by xfstests case xfs/098.
> 
> Fixes:'commit b04647edea32 ("xfs_repair: exit with status 2 if log dirtiness is unknown")'
> 
> Signed-off-by: Xiao Yang <yangx.jy@cn.fujitsu.com>

Whoops, yes this was a silly mistake, my fault, and definitely a bug -
and your fix is obviously correct.

However, your description isn't accurate; the bug exists only when
xlog_find_tail() fails to find the head or the tail, which
is why this went undiscovered for so long.  xfs_repair -L certainly
can clear a dirty log today, it only fails if xlog_find_tail fails.

The core bug here is missing braces; the result is that an unparseable
log always exits with exit(2), even if we've asked for -n or -L which
should proceed.

Can you resend this patch with a proper summary and a description
which more closely matches the actual bug?

Thanks,
-Eric

> ---
>  repair/phase2.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/repair/phase2.c b/repair/phase2.c
> index 992e997..c124882 100644
> --- a/repair/phase2.c
> +++ b/repair/phase2.c
> @@ -78,12 +78,13 @@ zero_log(
>  		do_warn(
>  		_("zero_log: cannot find log head/tail (xlog_find_tail=%d)\n"),
>  			error);
> -		if (!no_modify && !zap_log)
> +		if (!no_modify && !zap_log) {
>  			do_warn(_(
>  "ERROR: The log head and/or tail cannot be discovered. Attempt to mount the\n"
>  "filesystem to replay the log or use the -L option to destroy the log and\n"
>  "attempt a repair.\n"));
>  			exit(2);
> +		}
>  	} else {
>  		if (verbose) {
>  			do_log(
> 

Re: [PATCH] xfs_repair: Ensure just xfs_repair without -n can return a status code of 2

[Xiao Yang]

On 2018/02/27 22:21, Eric Sandeen wrote:
> On 2/26/18 11:50 PM, Xiao Yang wrote:
>> Since commit b04647edea32, xfs_repair -L could't succeed to clear a dirty log
>> and returned a status of 2.  Besides, xfs_repair -n returned a status of 2
>> instead of 1 if a dirty log was detected.  I think just xfs_repair without -n
>> should return a status code of 2 when getting a dirty log, so fix it.  We can
>> expose this issue by xfstests case xfs/098.
>>
>> Fixes:'commit b04647edea32 ("xfs_repair: exit with status 2 if log dirtiness is unknown")'
>>
>> Signed-off-by: Xiao Yang<yangx.jy@cn.fujitsu.com>
> Whoops, yes this was a silly mistake, my fault, and definitely a bug -
> and your fix is obviously correct.
>
> However, your description isn't accurate; the bug exists only when
> xlog_find_tail() fails to find the head or the tail, which
> is why this went undiscovered for so long.  xfs_repair -L certainly
> can clear a dirty log today, it only fails if xlog_find_tail fails.
>
> The core bug here is missing braces; the result is that an unparseable
> log always exits with exit(2), even if we've asked for -n or -L which
> should proceed.
>
> Can you resend this patch with a proper summary and a description
> which more closely matches the actual bug?
Hi Eric,

Thanks for your comment.
I will resend this patch as you suggested.

Thanks,
Xiao Yang
> Thanks,
> -Eric
>
>> ---
>>   repair/phase2.c | 3 ++-
>>   1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/repair/phase2.c b/repair/phase2.c
>> index 992e997..c124882 100644
>> --- a/repair/phase2.c
>> +++ b/repair/phase2.c
>> @@ -78,12 +78,13 @@ zero_log(
>>   		do_warn(
>>   		_("zero_log: cannot find log head/tail (xlog_find_tail=%d)\n"),
>>   			error);
>> -		if (!no_modify&&  !zap_log)
>> +		if (!no_modify&&  !zap_log) {
>>   			do_warn(_(
>>   "ERROR: The log head and/or tail cannot be discovered. Attempt to mount the\n"
>>   "filesystem to replay the log or use the -L option to destroy the log and\n"
>>   "attempt a repair.\n"));
>>   			exit(2);
>> +		}
>>   	} else {
>>   		if (verbose) {
>>   			do_log(
>>
>
> .
>

[PATCH v2] xfs_repair: Add missing braces

[Xiao Yang]

When xlog_find_tail() fails to find the head or the tail, the missing
braces leads that an unparseable log always exits with status 2, even
if we've asked for -n or -L which should proceed.  We can expose this
issue by xfstests case xfs/098.

Fixes:'commit b04647edea32 ("xfs_repair: exit with status 2 if log dirtiness is unknown")'

Signed-off-by: Xiao Yang <yangx.jy@cn.fujitsu.com>
---
 repair/phase2.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/repair/phase2.c b/repair/phase2.c
index 992e997..c124882 100644
--- a/repair/phase2.c
+++ b/repair/phase2.c
@@ -78,12 +78,13 @@ zero_log(
 		do_warn(
 		_("zero_log: cannot find log head/tail (xlog_find_tail=%d)\n"),
 			error);
-		if (!no_modify && !zap_log)
+		if (!no_modify && !zap_log) {
 			do_warn(_(
 "ERROR: The log head and/or tail cannot be discovered. Attempt to mount the\n"
 "filesystem to replay the log or use the -L option to destroy the log and\n"
 "attempt a repair.\n"));
 			exit(2);
+		}
 	} else {
 		if (verbose) {
 			do_log(
-- 
1.8.3.1

Re: [PATCH v2] xfs_repair: Add missing braces

[Eric Sandeen]

On 2/27/18 9:41 PM, Xiao Yang wrote:
> When xlog_find_tail() fails to find the head or the tail, the missing
> braces leads that an unparseable log always exits with status 2, even
> if we've asked for -n or -L which should proceed.  We can expose this
> issue by xfstests case xfs/098.
> 
> Fixes:'commit b04647edea32 ("xfs_repair: exit with status 2 if log dirtiness is unknown")'
> 
> Signed-off-by: Xiao Yang <yangx.jy@cn.fujitsu.com>

Thanks. I may make the subject more descriptive of the resulting
bug, but this is much better.

And thanks again for spotting it!

Reviewed-by: Eric Sandeen <sandeen@redhat.com>

> ---


>  repair/phase2.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/repair/phase2.c b/repair/phase2.c
> index 992e997..c124882 100644
> --- a/repair/phase2.c
> +++ b/repair/phase2.c
> @@ -78,12 +78,13 @@ zero_log(
>  		do_warn(
>  		_("zero_log: cannot find log head/tail (xlog_find_tail=%d)\n"),
>  			error);
> -		if (!no_modify && !zap_log)
> +		if (!no_modify && !zap_log) {
>  			do_warn(_(
>  "ERROR: The log head and/or tail cannot be discovered. Attempt to mount the\n"
>  "filesystem to replay the log or use the -L option to destroy the log and\n"
>  "attempt a repair.\n"));
>  			exit(2);
> +		}
>  	} else {
>  		if (verbose) {
>  			do_log(
>