[PATCH 1/4] xfs: Use variable-size array for nameval in xfs_attr_sf_entry

Carlos Maiolino
2020-08-31T13:06:51Z

nameval is a variable-size array, so, define it as it, and remove all
the -1 magic number subtractions.

Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
---
fs/xfs/libxfs/xfs_attr_leaf.c | 6 ++----
fs/xfs/libxfs/xfs_attr_sf.h | 6 +++---
fs/xfs/libxfs/xfs_da_format.h | 2 +-
3 files changed, 6 insertions(+), 8 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_attr_leaf.c b/fs/xfs/libxfs/xfs_attr_leaf.c
index 305d4bc073370..7bbc97e0e4d4a 100644
--- a/fs/xfs/libxfs/xfs_attr_leaf.c
+++ b/fs/xfs/libxfs/xfs_attr_leaf.c
@@ -992,7 +992,7 @@ xfs_attr_shortform_allfit(
return 0;
if (be16_to_cpu(name_loc->valuelen) >= XFS_ATTR_SF_ENTSIZE_MAX)
return 0;
- bytes += sizeof(struct xfs_attr_sf_entry) - 1
+ bytes += sizeof(struct xfs_attr_sf_entry)
+ name_loc->namelen
+ be16_to_cpu(name_loc->valuelen);
}
@@ -1036,10 +1036,8 @@ xfs_attr_shortform_verify(
* struct xfs_attr_sf_entry has a variable length.
* Check the fixed-offset parts of the structure are
* within the data buffer.
- * xfs_attr_sf_entry is defined with a 1-byte variable
- * array at the end, so we must subtract that off.
*/
- if (((char *)sfep + sizeof(*sfep) - 1) >= endp)
+ if (((char *)sfep + sizeof(*sfep)) >= endp)
return __this_address;

/* Don't allow names with known bad length. */
diff --git a/fs/xfs/libxfs/xfs_attr_sf.h b/fs/xfs/libxfs/xfs_attr_sf.h
index bb004fb7944a7..d93012a0be4d0 100644
--- a/fs/xfs/libxfs/xfs_attr_sf.h
+++ b/fs/xfs/libxfs/xfs_attr_sf.h
@@ -28,11 +28,11 @@ typedef struct xfs_attr_sf_sort {
} xfs_attr_sf_sort_t;

#define XFS_ATTR_SF_ENTSIZE_BYNAME(nlen,vlen) /* space name/value uses */ \
- (((int)sizeof(xfs_attr_sf_entry_t)-1 + (nlen)+(vlen)))
+ (((int)sizeof(xfs_attr_sf_entry_t) + (nlen)+(vlen)))
#define XFS_ATTR_SF_ENTSIZE_MAX /* max space for name&value */ \
- ((1 << (NBBY*(int)sizeof(uint8_t))) - 1)
+ (1 << (NBBY*(int)sizeof(uint8_t)))
#define XFS_ATTR_SF_ENTSIZE(sfep) /* space an entry uses */ \
- ((int)sizeof(xfs_attr_sf_entry_t)-1 + (sfep)->namelen+(sfep)->valuelen)
+ ((int)sizeof(xfs_attr_sf_entry_t) + (sfep)->namelen+(sfep)->valuelen)
#define XFS_ATTR_SF_NEXTENTRY(sfep) /* next entry in struct */ \
((xfs_attr_sf_entry_t *)((char *)(sfep) + XFS_ATTR_SF_ENTSIZE(sfep)))
#define XFS_ATTR_SF_TOTSIZE(dp) /* total space in use */ \
diff --git a/fs/xfs/libxfs/xfs_da_format.h b/fs/xfs/libxfs/xfs_da_format.h
index 059ac108b1b39..e86185a1165b3 100644
--- a/fs/xfs/libxfs/xfs_da_format.h
+++ b/fs/xfs/libxfs/xfs_da_format.h
@@ -589,7 +589,7 @@ typedef struct xfs_attr_shortform {
uint8_t namelen; /* actual length of name (no NULL) */
uint8_t valuelen; /* actual length of value (no NULL) */
uint8_t flags; /* flags bits (see xfs_attr_leaf.h) */
- uint8_t nameval[1]; /* name & value bytes concatenated */
+ uint8_t nameval[]; /* name & value bytes concatenated */
} list[1]; /* variable sized array */
} xfs_attr_shortform_t;

--
2.26.2