Re: [PATCH 1/2] exfat: add dir-entry set checksum validation

2020-08-12 Thread Tetsuhiro Kohada 

Thnak you for your reply.


-void exfat_update_dir_chksum_with_entry_set(struct exfat_entry_set_cache *es)
+static int exfat_calc_dir_chksum_with_entry_set(struct
+exfat_entry_set_cache *es, u16 *chksum)
  {
-   int chksum_type = CS_DIR_ENTRY, i;
-   unsigned short chksum = 0;
struct exfat_dentry *ep;
+   int i;

-   for (i = 0; i < es->num_entries; i++) {
-   ep = exfat_get_validated_dentry(es, i, TYPE_ALL);
-   chksum = exfat_calc_chksum16(ep, DENTRY_SIZE, chksum,
-chksum_type);
-   chksum_type = CS_DEFAULT;
+   ep = container_of(es->de_file, struct exfat_dentry, dentry.file);
+   *chksum = exfat_calc_chksum16(ep, DENTRY_SIZE, 0, CS_DIR_ENTRY);
+   for (i = 0; i < es->de_file->num_ext; i++) {
+   ep = exfat_get_validated_dentry(es, 1 + i, TYPE_SECONDARY);
+   if (!ep)
+   return -EIO;
+   *chksum = exfat_calc_chksum16(ep, DENTRY_SIZE, *chksum, 
CS_DEFAULT);
}
+   return 0;

We can return checksum after removing u16 *chksum argument.


I want to do that too!
How should I return the error?

Right now, I found that the type of chksum is not 'u16'.
I'll fix in v2.



+}
+
+void exfat_update_dir_chksum_with_entry_set(struct
+exfat_entry_set_cache *es) {
+   u16 chksum;
+
+   exfat_calc_dir_chksum_with_entry_set(es, );
es->de_file->checksum = cpu_to_le16(chksum);
es->modified = true;
  }
@@ -775,6 +784,7 @@ struct exfat_entry_set_cache *exfat_get_dentry_set(struct 
super_block *sb,
struct exfat_entry_set_cache *es;
struct exfat_dentry *ep;
struct buffer_head *bh;
+   u16 chksum;

if (p_dir->dir == DIR_DELETED) {
exfat_err(sb, "access to deleted dentry"); @@ -839,10 +849,10 
@@ struct
exfat_entry_set_cache *exfat_get_dentry_set(struct super_block *sb,
goto free_es;
es->de_stream = >dentry.stream;

-   for (i = 2; i < es->num_entries; i++) {
-   if (!exfat_get_validated_dentry(es, i, TYPE_SECONDARY))
-   goto free_es;
-   }
+   if (max_entries == ES_ALL_ENTRIES &&
+   ((exfat_calc_dir_chksum_with_entry_set(es, ) ||
+ chksum != le16_to_cpu(es->de_file->checksum

Please add error print log if checksum mismatch error happen.


OK.
I'll add in v2.


BR
---
Tetsuhiro Kohada

RE: [PATCH 1/2] exfat: add dir-entry set checksum validation

2020-08-10 Thread Namjae Jeon 
> Add checksum validation for dir-entry set when getting it.
> exfat_calc_dir_chksum_with_entry_set() also validates entry-type.
> 
> ** This patch depends on:
>   '[PATCH v3] exfat: integrates dir-entry getting and validation'
> 
> Signed-off-by: Tetsuhiro Kohada 
> ---
>  fs/exfat/dir.c | 34 ++
>  1 file changed, 22 insertions(+), 12 deletions(-)
> 
> diff --git a/fs/exfat/dir.c b/fs/exfat/dir.c index c9715c7a55a1..2e79ac464f5f 
> 100644
> --- a/fs/exfat/dir.c
> +++ b/fs/exfat/dir.c
> @@ -563,18 +563,27 @@ int exfat_remove_entries(struct inode *inode, struct 
> exfat_chain *p_dir,
>   return 0;
>  }
> 
> -void exfat_update_dir_chksum_with_entry_set(struct exfat_entry_set_cache *es)
> +static int exfat_calc_dir_chksum_with_entry_set(struct
> +exfat_entry_set_cache *es, u16 *chksum)
>  {
> - int chksum_type = CS_DIR_ENTRY, i;
> - unsigned short chksum = 0;
>   struct exfat_dentry *ep;
> + int i;
> 
> - for (i = 0; i < es->num_entries; i++) {
> - ep = exfat_get_validated_dentry(es, i, TYPE_ALL);
> - chksum = exfat_calc_chksum16(ep, DENTRY_SIZE, chksum,
> -  chksum_type);
> - chksum_type = CS_DEFAULT;
> + ep = container_of(es->de_file, struct exfat_dentry, dentry.file);
> + *chksum = exfat_calc_chksum16(ep, DENTRY_SIZE, 0, CS_DIR_ENTRY);
> + for (i = 0; i < es->de_file->num_ext; i++) {
> + ep = exfat_get_validated_dentry(es, 1 + i, TYPE_SECONDARY);
> + if (!ep)
> + return -EIO;
> + *chksum = exfat_calc_chksum16(ep, DENTRY_SIZE, *chksum, 
> CS_DEFAULT);
>   }
> + return 0;
We can return checksum after removing u16 *chksum argument.
> +}
> +
> +void exfat_update_dir_chksum_with_entry_set(struct
> +exfat_entry_set_cache *es) {
> + u16 chksum;
> +
> + exfat_calc_dir_chksum_with_entry_set(es, );
>   es->de_file->checksum = cpu_to_le16(chksum);
>   es->modified = true;
>  }
> @@ -775,6 +784,7 @@ struct exfat_entry_set_cache *exfat_get_dentry_set(struct 
> super_block *sb,
>   struct exfat_entry_set_cache *es;
>   struct exfat_dentry *ep;
>   struct buffer_head *bh;
> + u16 chksum;
> 
>   if (p_dir->dir == DIR_DELETED) {
>   exfat_err(sb, "access to deleted dentry"); @@ -839,10 +849,10 
> @@ struct
> exfat_entry_set_cache *exfat_get_dentry_set(struct super_block *sb,
>   goto free_es;
>   es->de_stream = >dentry.stream;
> 
> - for (i = 2; i < es->num_entries; i++) {
> - if (!exfat_get_validated_dentry(es, i, TYPE_SECONDARY))
> - goto free_es;
> - }
> + if (max_entries == ES_ALL_ENTRIES &&
> + ((exfat_calc_dir_chksum_with_entry_set(es, ) ||
> +   chksum != le16_to_cpu(es->de_file->checksum
Please add error print log if checksum mismatch error happen.
> + goto free_es;
> 
>   return es;
> 
> --
> 2.25.1

[PATCH 1/2] exfat: add dir-entry set checksum validation

2020-08-07 Thread Tetsuhiro Kohada 
Add checksum validation for dir-entry set when getting it.
exfat_calc_dir_chksum_with_entry_set() also validates entry-type.

** This patch depends on:
  '[PATCH v3] exfat: integrates dir-entry getting and validation'

Signed-off-by: Tetsuhiro Kohada 
---
 fs/exfat/dir.c | 34 ++
 1 file changed, 22 insertions(+), 12 deletions(-)

diff --git a/fs/exfat/dir.c b/fs/exfat/dir.c
index c9715c7a55a1..2e79ac464f5f 100644
--- a/fs/exfat/dir.c
+++ b/fs/exfat/dir.c
@@ -563,18 +563,27 @@ int exfat_remove_entries(struct inode *inode, struct 
exfat_chain *p_dir,
return 0;
 }
 
-void exfat_update_dir_chksum_with_entry_set(struct exfat_entry_set_cache *es)
+static int exfat_calc_dir_chksum_with_entry_set(struct exfat_entry_set_cache 
*es, u16 *chksum)
 {
-   int chksum_type = CS_DIR_ENTRY, i;
-   unsigned short chksum = 0;
struct exfat_dentry *ep;
+   int i;
 
-   for (i = 0; i < es->num_entries; i++) {
-   ep = exfat_get_validated_dentry(es, i, TYPE_ALL);
-   chksum = exfat_calc_chksum16(ep, DENTRY_SIZE, chksum,
-chksum_type);
-   chksum_type = CS_DEFAULT;
+   ep = container_of(es->de_file, struct exfat_dentry, dentry.file);
+   *chksum = exfat_calc_chksum16(ep, DENTRY_SIZE, 0, CS_DIR_ENTRY);
+   for (i = 0; i < es->de_file->num_ext; i++) {
+   ep = exfat_get_validated_dentry(es, 1 + i, TYPE_SECONDARY);
+   if (!ep)
+   return -EIO;
+   *chksum = exfat_calc_chksum16(ep, DENTRY_SIZE, *chksum, 
CS_DEFAULT);
}
+   return 0;
+}
+
+void exfat_update_dir_chksum_with_entry_set(struct exfat_entry_set_cache *es)
+{
+   u16 chksum;
+
+   exfat_calc_dir_chksum_with_entry_set(es, );
es->de_file->checksum = cpu_to_le16(chksum);
es->modified = true;
 }
@@ -775,6 +784,7 @@ struct exfat_entry_set_cache *exfat_get_dentry_set(struct 
super_block *sb,
struct exfat_entry_set_cache *es;
struct exfat_dentry *ep;
struct buffer_head *bh;
+   u16 chksum;
 
if (p_dir->dir == DIR_DELETED) {
exfat_err(sb, "access to deleted dentry");
@@ -839,10 +849,10 @@ struct exfat_entry_set_cache *exfat_get_dentry_set(struct 
super_block *sb,
goto free_es;
es->de_stream = >dentry.stream;
 
-   for (i = 2; i < es->num_entries; i++) {
-   if (!exfat_get_validated_dentry(es, i, TYPE_SECONDARY))
-   goto free_es;
-   }
+   if (max_entries == ES_ALL_ENTRIES &&
+   ((exfat_calc_dir_chksum_with_entry_set(es, ) ||
+ chksum != le16_to_cpu(es->de_file->checksum
+   goto free_es;
 
return es;
 
-- 
2.25.1