[PATCH] Fix serious memory leak

[PATCH] Fix serious memory leak

[Lukasz Dorau]

During reshape function restore_stripes is called periodically
and every time the buffer stripe_buf (of size raid_disks*chunk_size)
is allocated but is not freed. It happens also upon successful completion.
In case of huge arrays it can lead to the seizure of the entire
system memory (even of the order of gigabytes).

Signed-off-by: Lukasz Dorau <lukasz.dorau@intel.com>
---
 restripe.c |   43 +++++++++++++++++++++++++++++++------------
 1 files changed, 31 insertions(+), 12 deletions(-)

diff --git a/restripe.c b/restripe.c
index 9c83e2e..7cabbd0 100644
--- a/restripe.c
+++ b/restripe.c
@@ -687,6 +687,7 @@ int restore_stripes(int *dest, unsigned long long *offsets,
 	char **stripes = malloc(raid_disks * sizeof(char*));
 	char **blocks = malloc(raid_disks * sizeof(char*));
 	int i;
+	int rv = 0;
 
 	int data_disks = raid_disks - (level == 0 ? 0 : level <= 5 ? 1 : 2);
 
@@ -717,20 +718,26 @@ int restore_stripes(int *dest, unsigned long long *offsets,
 		unsigned long long offset;
 		int disk, qdisk;
 		int syndrome_disks;
-		if (length < len)
-			return -3;
+		if (length < len) {
+			rv = -3;
+			goto abort;
+		}
 		for (i = 0; i < data_disks; i++) {
 			int disk = geo_map(i, start/chunk_size/data_disks,
 					   raid_disks, level, layout);
 			if (src_buf == NULL) {
 				/* read from file */
-				if (lseek64(source,
-					read_offset, 0) != (off64_t)read_offset)
-					return -1;
+				if (lseek64(source, read_offset, 0) !=
+					 (off64_t)read_offset) {
+					rv = -1;
+					goto abort;
+				}
 				if (read(source,
 					 stripes[disk],
-					 chunk_size) != chunk_size)
-					return -1;
+					 chunk_size) != chunk_size) {
+					rv = -1;
+					goto abort;
+				}
 			} else {
 				/* read from input buffer */
 				memcpy(stripes[disk],
@@ -782,15 +789,27 @@ int restore_stripes(int *dest, unsigned long long *offsets,
 		}
 		for (i=0; i < raid_disks ; i++)
 			if (dest[i] >= 0) {
-				if (lseek64(dest[i], offsets[i]+offset, 0) < 0)
-					return -1;
-				if (write(dest[i], stripes[i], chunk_size) != chunk_size)
-					return -1;
+				if (lseek64(dest[i],
+					 offsets[i]+offset, 0) < 0) {
+					rv = -1;
+					goto abort;
+				}
+				if (write(dest[i], stripes[i],
+					 chunk_size) != chunk_size) {
+					rv = -1;
+					goto abort;
+				}
 			}
 		length -= len;
 		start += len;
 	}
-	return 0;
+	rv = 0;
+
+abort:
+	free(stripe_buf);
+	free(stripes);
+	free(blocks);
+	return rv;
 }
 
 #ifdef MAIN

Re: [PATCH] Fix serious memory leak

[NeilBrown]

[-- Attachment #1: Type: text/plain, Size: 3272 bytes --]

On Fri, 16 Sep 2011 13:19:14 +0200 Lukasz Dorau <lukasz.dorau@intel.com>
wrote:

> During reshape function restore_stripes is called periodically
> and every time the buffer stripe_buf (of size raid_disks*chunk_size)
> is allocated but is not freed. It happens also upon successful completion.
> In case of huge arrays it can lead to the seizure of the entire
> system memory (even of the order of gigabytes).
> 
> Signed-off-by: Lukasz Dorau <lukasz.dorau@intel.com>

Thanks.

I changed that patch a bit:
 - There were two places that freed everything and returned.  I changed the
   first one to just set 'rv' and 'goto' the last one.
 - You set 'rv = 0' twice.  Once is enough.  I removed the first one.

Thanks,

NeilBrown


> ---
>  restripe.c |   43 +++++++++++++++++++++++++++++++------------
>  1 files changed, 31 insertions(+), 12 deletions(-)
> 
> diff --git a/restripe.c b/restripe.c
> index 9c83e2e..7cabbd0 100644
> --- a/restripe.c
> +++ b/restripe.c
> @@ -687,6 +687,7 @@ int restore_stripes(int *dest, unsigned long long *offsets,
>  	char **stripes = malloc(raid_disks * sizeof(char*));
>  	char **blocks = malloc(raid_disks * sizeof(char*));
>  	int i;
> +	int rv = 0;
>  
>  	int data_disks = raid_disks - (level == 0 ? 0 : level <= 5 ? 1 : 2);
>  
> @@ -717,20 +718,26 @@ int restore_stripes(int *dest, unsigned long long *offsets,
>  		unsigned long long offset;
>  		int disk, qdisk;
>  		int syndrome_disks;
> -		if (length < len)
> -			return -3;
> +		if (length < len) {
> +			rv = -3;
> +			goto abort;
> +		}
>  		for (i = 0; i < data_disks; i++) {
>  			int disk = geo_map(i, start/chunk_size/data_disks,
>  					   raid_disks, level, layout);
>  			if (src_buf == NULL) {
>  				/* read from file */
> -				if (lseek64(source,
> -					read_offset, 0) != (off64_t)read_offset)
> -					return -1;
> +				if (lseek64(source, read_offset, 0) !=
> +					 (off64_t)read_offset) {
> +					rv = -1;
> +					goto abort;
> +				}
>  				if (read(source,
>  					 stripes[disk],
> -					 chunk_size) != chunk_size)
> -					return -1;
> +					 chunk_size) != chunk_size) {
> +					rv = -1;
> +					goto abort;
> +				}
>  			} else {
>  				/* read from input buffer */
>  				memcpy(stripes[disk],
> @@ -782,15 +789,27 @@ int restore_stripes(int *dest, unsigned long long *offsets,
>  		}
>  		for (i=0; i < raid_disks ; i++)
>  			if (dest[i] >= 0) {
> -				if (lseek64(dest[i], offsets[i]+offset, 0) < 0)
> -					return -1;
> -				if (write(dest[i], stripes[i], chunk_size) != chunk_size)
> -					return -1;
> +				if (lseek64(dest[i],
> +					 offsets[i]+offset, 0) < 0) {
> +					rv = -1;
> +					goto abort;
> +				}
> +				if (write(dest[i], stripes[i],
> +					 chunk_size) != chunk_size) {
> +					rv = -1;
> +					goto abort;
> +				}
>  			}
>  		length -= len;
>  		start += len;
>  	}
> -	return 0;
> +	rv = 0;
> +
> +abort:
> +	free(stripe_buf);
> +	free(stripes);
> +	free(blocks);
> +	return rv;
>  }
>  
>  #ifdef MAIN
> 
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