From 2a6fba6d2311151598abaa1e7c9abd5f8d024a43 Mon Sep 17 00:00:00 2001 From: Eric Sandeen Date: Wed, 6 Apr 2016 07:57:18 +1000 Subject: [PATCH 1/4] xfs: only return -errno or success from attr ->put_listent Today, the put_listent formatters return either 1 or 0; if they return 1, some callers treat this as an error and return it up the stack, despite "1" not being a valid (negative) error code. The intent seems to be that if the input buffer is full, we set seen_enough or set count = -1, and return 1; but some callers check the return before checking the seen_enough or count fields of the context. Fix this by only returning non-zero for actual errors encountered, and rely on the caller to first check the return value, then check the values in the context to decide what to do. Signed-off-by: Eric Sandeen Reviewed-by: Christoph Hellwig Signed-off-by: Dave Chinner --- fs/xfs/xfs_attr.h | 1 + fs/xfs/xfs_attr_list.c | 8 +++----- fs/xfs/xfs_xattr.c | 14 ++++++++++---- 3 files changed, 14 insertions(+), 9 deletions(-) diff --git a/fs/xfs/xfs_attr.h b/fs/xfs/xfs_attr.h index dd4824589470..234331227c0c 100644 --- a/fs/xfs/xfs_attr.h +++ b/fs/xfs/xfs_attr.h @@ -112,6 +112,7 @@ typedef struct attrlist_cursor_kern { *========================================================================*/ +/* Return 0 on success, or -errno; other state communicated via *context */ typedef int (*put_listent_func_t)(struct xfs_attr_list_context *, int, unsigned char *, int, int, unsigned char *); diff --git a/fs/xfs/xfs_attr_list.c b/fs/xfs/xfs_attr_list.c index 4fa14820e2e2..c8be331a3196 100644 --- a/fs/xfs/xfs_attr_list.c +++ b/fs/xfs/xfs_attr_list.c @@ -108,16 +108,14 @@ xfs_attr_shortform_list(xfs_attr_list_context_t *context) (int)sfe->namelen, (int)sfe->valuelen, &sfe->nameval[sfe->namelen]); - + if (error) + return error; /* * Either search callback finished early or * didn't fit it all in the buffer after all. */ if (context->seen_enough) break; - - if (error) - return error; sfe = XFS_ATTR_SF_NEXTENTRY(sfe); } trace_xfs_attr_list_sf_all(context); @@ -581,7 +579,7 @@ xfs_attr_put_listent( trace_xfs_attr_list_full(context); alist->al_more = 1; context->seen_enough = 1; - return 1; + return 0; } aep = (attrlist_ent_t *)&context->alist[context->firstu]; diff --git a/fs/xfs/xfs_xattr.c b/fs/xfs/xfs_xattr.c index 110f1d7d86b0..f2201299311f 100644 --- a/fs/xfs/xfs_xattr.c +++ b/fs/xfs/xfs_xattr.c @@ -146,7 +146,7 @@ __xfs_xattr_put_listent( arraytop = context->count + prefix_len + namelen + 1; if (arraytop > context->firstu) { context->count = -1; /* insufficient space */ - return 1; + return 0; } offset = (char *)context->alist + context->count; strncpy(offset, prefix, prefix_len); @@ -221,11 +221,15 @@ xfs_xattr_put_listent( } ssize_t -xfs_vn_listxattr(struct dentry *dentry, char *data, size_t size) +xfs_vn_listxattr( + struct dentry *dentry, + char *data, + size_t size) { struct xfs_attr_list_context context; struct attrlist_cursor_kern cursor = { 0 }; - struct inode *inode = d_inode(dentry); + struct inode *inode = d_inode(dentry); + int error; /* * First read the regular on-disk attributes. @@ -239,7 +243,9 @@ xfs_vn_listxattr(struct dentry *dentry, char *data, size_t size) context.firstu = context.bufsize; context.put_listent = xfs_xattr_put_listent; - xfs_attr_list_int(&context); + error = xfs_attr_list_int(&context); + if (error) + return error; if (context.count < 0) return -ERANGE; From e5bd12bfea60af455f4cbad494e4ac1082e3abd6 Mon Sep 17 00:00:00 2001 From: Eric Sandeen Date: Wed, 6 Apr 2016 07:57:32 +1000 Subject: [PATCH 2/4] xfs: don't pass value into attr ->put_listent The value is not used; only names and value lengths are returned. Remove the argument. Signed-off-by: Eric Sandeen Reviewed-by: Christoph Hellwig Signed-off-by: Dave Chinner --- fs/xfs/xfs_attr.h | 2 +- fs/xfs/xfs_attr_list.c | 18 ++++++------------ fs/xfs/xfs_xattr.c | 3 +-- 3 files changed, 8 insertions(+), 15 deletions(-) diff --git a/fs/xfs/xfs_attr.h b/fs/xfs/xfs_attr.h index 234331227c0c..dab4f41de278 100644 --- a/fs/xfs/xfs_attr.h +++ b/fs/xfs/xfs_attr.h @@ -114,7 +114,7 @@ typedef struct attrlist_cursor_kern { /* Return 0 on success, or -errno; other state communicated via *context */ typedef int (*put_listent_func_t)(struct xfs_attr_list_context *, int, - unsigned char *, int, int, unsigned char *); + unsigned char *, int, int); typedef struct xfs_attr_list_context { struct xfs_inode *dp; /* inode */ diff --git a/fs/xfs/xfs_attr_list.c b/fs/xfs/xfs_attr_list.c index c8be331a3196..d30dbfae05fe 100644 --- a/fs/xfs/xfs_attr_list.c +++ b/fs/xfs/xfs_attr_list.c @@ -106,8 +106,7 @@ xfs_attr_shortform_list(xfs_attr_list_context_t *context) sfe->flags, sfe->nameval, (int)sfe->namelen, - (int)sfe->valuelen, - &sfe->nameval[sfe->namelen]); + (int)sfe->valuelen); if (error) return error; /* @@ -198,8 +197,7 @@ xfs_attr_shortform_list(xfs_attr_list_context_t *context) sbp->flags, sbp->name, sbp->namelen, - sbp->valuelen, - &sbp->name[sbp->namelen]); + sbp->valuelen); if (error) { kmem_free(sbuf); return error; @@ -430,8 +428,7 @@ xfs_attr3_leaf_list_int( entry->flags, name_loc->nameval, (int)name_loc->namelen, - be16_to_cpu(name_loc->valuelen), - &name_loc->nameval[name_loc->namelen]); + be16_to_cpu(name_loc->valuelen)); if (retval) return retval; } else { @@ -459,16 +456,14 @@ xfs_attr3_leaf_list_int( entry->flags, name_rmt->name, (int)name_rmt->namelen, - valuelen, - args.value); + valuelen); kmem_free(args.value); } else { retval = context->put_listent(context, entry->flags, name_rmt->name, (int)name_rmt->namelen, - valuelen, - NULL); + valuelen); } if (retval) return retval; @@ -549,8 +544,7 @@ xfs_attr_put_listent( int flags, unsigned char *name, int namelen, - int valuelen, - unsigned char *value) + int valuelen) { struct attrlist *alist = (struct attrlist *)context->alist; attrlist_ent_t *aep; diff --git a/fs/xfs/xfs_xattr.c b/fs/xfs/xfs_xattr.c index f2201299311f..7fdcf3327652 100644 --- a/fs/xfs/xfs_xattr.c +++ b/fs/xfs/xfs_xattr.c @@ -166,8 +166,7 @@ xfs_xattr_put_listent( int flags, unsigned char *name, int namelen, - int valuelen, - unsigned char *value) + int valuelen) { char *prefix; int prefix_len; From 7af5ad28a603f2d1ef4c579b8ab0a9d4767a348e Mon Sep 17 00:00:00 2001 From: Eric Sandeen Date: Wed, 6 Apr 2016 07:57:45 +1000 Subject: [PATCH 3/4] xfs: remove put_value from attr ->put_listent context The put_value context member is never set; remove it and the conditional test in xfs_attr3_leaf_list_int(). Signed-off-by: Eric Sandeen Reviewed-by: Christoph Hellwig Signed-off-by: Dave Chinner --- fs/xfs/xfs_attr.h | 1 - fs/xfs/xfs_attr_list.c | 31 +++---------------------------- 2 files changed, 3 insertions(+), 29 deletions(-) diff --git a/fs/xfs/xfs_attr.h b/fs/xfs/xfs_attr.h index dab4f41de278..e3da5d448bcf 100644 --- a/fs/xfs/xfs_attr.h +++ b/fs/xfs/xfs_attr.h @@ -127,7 +127,6 @@ typedef struct xfs_attr_list_context { int firstu; /* first used byte in buffer */ int flags; /* from VOP call */ int resynch; /* T/F: resynch with cursor */ - int put_value; /* T/F: need value for listent */ put_listent_func_t put_listent; /* list output fmt function */ int index; /* index into output buffer */ } xfs_attr_list_context_t; diff --git a/fs/xfs/xfs_attr_list.c b/fs/xfs/xfs_attr_list.c index d30dbfae05fe..cbf4f5d072f6 100644 --- a/fs/xfs/xfs_attr_list.c +++ b/fs/xfs/xfs_attr_list.c @@ -429,45 +429,20 @@ xfs_attr3_leaf_list_int( name_loc->nameval, (int)name_loc->namelen, be16_to_cpu(name_loc->valuelen)); - if (retval) - return retval; } else { xfs_attr_leaf_name_remote_t *name_rmt = xfs_attr3_leaf_name_remote(leaf, i); int valuelen = be32_to_cpu(name_rmt->valuelen); - if (context->put_value) { - xfs_da_args_t args; - - memset((char *)&args, 0, sizeof(args)); - args.geo = context->dp->i_mount->m_attr_geo; - args.dp = context->dp; - args.whichfork = XFS_ATTR_FORK; - args.valuelen = valuelen; - args.rmtvaluelen = valuelen; - args.value = kmem_alloc(valuelen, KM_SLEEP | KM_NOFS); - args.rmtblkno = be32_to_cpu(name_rmt->valueblk); - args.rmtblkcnt = xfs_attr3_rmt_blocks( - args.dp->i_mount, valuelen); - retval = xfs_attr_rmtval_get(&args); - if (!retval) - retval = context->put_listent(context, - entry->flags, - name_rmt->name, - (int)name_rmt->namelen, - valuelen); - kmem_free(args.value); - } else { - retval = context->put_listent(context, + retval = context->put_listent(context, entry->flags, name_rmt->name, (int)name_rmt->namelen, valuelen); - } - if (retval) - return retval; } + if (retval) + break; if (context->seen_enough) break; cursor->offset++; From 3ab3ffcaca99e0b77480d77bd393fc227b09069f Mon Sep 17 00:00:00 2001 From: Eric Sandeen Date: Wed, 6 Apr 2016 07:57:47 +1000 Subject: [PATCH 4/4] xfs: collapse cases in xfs_attr3_leaf_list_int Consolidate the 2 calls to ->put_listent in xfs_attr3_leaf_list_int(), by setting up name, namelen, and valuelen for the local vs remote cases, then call ->put_listent and do the error handling all in one spot. Signed-off-by: Eric Sandeen --- fs/xfs/xfs_attr_list.c | 32 ++++++++++++++++---------------- 1 file changed, 16 insertions(+), 16 deletions(-) diff --git a/fs/xfs/xfs_attr_list.c b/fs/xfs/xfs_attr_list.c index cbf4f5d072f6..d25f26b22ac9 100644 --- a/fs/xfs/xfs_attr_list.c +++ b/fs/xfs/xfs_attr_list.c @@ -412,6 +412,9 @@ xfs_attr3_leaf_list_int( */ retval = 0; for (; i < ichdr.count; entry++, i++) { + char *name; + int namelen, valuelen; + if (be32_to_cpu(entry->hashval) != cursor->hashval) { cursor->hashval = be32_to_cpu(entry->hashval); cursor->offset = 0; @@ -421,26 +424,23 @@ xfs_attr3_leaf_list_int( continue; /* skip incomplete entries */ if (entry->flags & XFS_ATTR_LOCAL) { - xfs_attr_leaf_name_local_t *name_loc = - xfs_attr3_leaf_name_local(leaf, i); + xfs_attr_leaf_name_local_t *name_loc; - retval = context->put_listent(context, - entry->flags, - name_loc->nameval, - (int)name_loc->namelen, - be16_to_cpu(name_loc->valuelen)); + name_loc = xfs_attr3_leaf_name_local(leaf, i); + name = name_loc->nameval; + namelen = name_loc->namelen; + valuelen = be16_to_cpu(name_loc->valuelen); } else { - xfs_attr_leaf_name_remote_t *name_rmt = - xfs_attr3_leaf_name_remote(leaf, i); + xfs_attr_leaf_name_remote_t *name_rmt; - int valuelen = be32_to_cpu(name_rmt->valuelen); - - retval = context->put_listent(context, - entry->flags, - name_rmt->name, - (int)name_rmt->namelen, - valuelen); + name_rmt = xfs_attr3_leaf_name_remote(leaf, i); + name = name_rmt->name; + namelen = name_rmt->namelen; + valuelen = be32_to_cpu(name_rmt->valuelen); } + + retval = context->put_listent(context, entry->flags, + name, namelen, valuelen); if (retval) break; if (context->seen_enough)