diff options
| -rw-r--r-- | fs/ceph/xattr.c | 84 |
1 files changed, 59 insertions, 25 deletions
diff --git a/fs/ceph/xattr.c b/fs/ceph/xattr.c index 9b77dca0b786..37b458a9af3a 100644 --- a/fs/ceph/xattr.c +++ b/fs/ceph/xattr.c @@ -109,22 +109,49 @@ static ssize_t ceph_vxattrcb_layout(struct ceph_inode_info *ci, char *val, return ret; } +/* + * The convention with strings in xattrs is that they should not be NULL + * terminated, since we're returning the length with them. snprintf always + * NULL terminates however, so call it on a temporary buffer and then memcpy + * the result into place. + */ +static int ceph_fmt_xattr(char *val, size_t size, const char *fmt, ...) +{ + int ret; + va_list args; + char buf[96]; /* NB: reevaluate size if new vxattrs are added */ + + va_start(args, fmt); + ret = vsnprintf(buf, size ? sizeof(buf) : 0, fmt, args); + va_end(args); + + /* Sanity check */ + if (size && ret + 1 > sizeof(buf)) { + WARN_ONCE(true, "Returned length too big (%d)", ret); + return -E2BIG; + } + + if (ret <= size) + memcpy(val, buf, ret); + return ret; +} + static ssize_t ceph_vxattrcb_layout_stripe_unit(struct ceph_inode_info *ci, char *val, size_t size) { - return snprintf(val, size, "%u", ci->i_layout.stripe_unit); + return ceph_fmt_xattr(val, size, "%u", ci->i_layout.stripe_unit); } static ssize_t ceph_vxattrcb_layout_stripe_count(struct ceph_inode_info *ci, char *val, size_t size) { - return snprintf(val, size, "%u", ci->i_layout.stripe_count); + return ceph_fmt_xattr(val, size, "%u", ci->i_layout.stripe_count); } static ssize_t ceph_vxattrcb_layout_object_size(struct ceph_inode_info *ci, char *val, size_t size) { - return snprintf(val, size, "%u", ci->i_layout.object_size); + return ceph_fmt_xattr(val, size, "%u", ci->i_layout.object_size); } static ssize_t ceph_vxattrcb_layout_pool(struct ceph_inode_info *ci, @@ -138,10 +165,13 @@ static ssize_t ceph_vxattrcb_layout_pool(struct ceph_inode_info *ci, down_read(&osdc->lock); pool_name = ceph_pg_pool_name_by_id(osdc->osdmap, pool); - if (pool_name) - ret = snprintf(val, size, "%s", pool_name); - else - ret = snprintf(val, size, "%lld", pool); + if (pool_name) { + ret = strlen(pool_name); + if (ret <= size) + memcpy(val, pool_name, ret); + } else { + ret = ceph_fmt_xattr(val, size, "%lld", pool); + } up_read(&osdc->lock); return ret; } @@ -149,10 +179,13 @@ static ssize_t ceph_vxattrcb_layout_pool(struct ceph_inode_info *ci, static ssize_t ceph_vxattrcb_layout_pool_namespace(struct ceph_inode_info *ci, char *val, size_t size) { - int ret = 0; + ssize_t ret = 0; struct ceph_string *ns = ceph_try_get_string(ci->i_layout.pool_ns); + if (ns) { - ret = snprintf(val, size, "%.*s", ns->len, ns->str); + ret = ns->len; + if (ret <= size) + memcpy(val, ns->str, ret); ceph_put_string(ns); } return ret; @@ -163,50 +196,51 @@ static ssize_t ceph_vxattrcb_layout_pool_namespace(struct ceph_inode_info *ci, static ssize_t ceph_vxattrcb_dir_entries(struct ceph_inode_info *ci, char *val, size_t size) { - return snprintf(val, size, "%lld", ci->i_files + ci->i_subdirs); + return ceph_fmt_xattr(val, size, "%lld", ci->i_files + ci->i_subdirs); } static ssize_t ceph_vxattrcb_dir_files(struct ceph_inode_info *ci, char *val, size_t size) { - return snprintf(val, size, "%lld", ci->i_files); + return ceph_fmt_xattr(val, size, "%lld", ci->i_files); } static ssize_t ceph_vxattrcb_dir_subdirs(struct ceph_inode_info *ci, char *val, size_t size) { - return snprintf(val, size, "%lld", ci->i_subdirs); + return ceph_fmt_xattr(val, size, "%lld", ci->i_subdirs); } static ssize_t ceph_vxattrcb_dir_rentries(struct ceph_inode_info *ci, char *val, size_t size) { - return snprintf(val, size, "%lld", ci->i_rfiles + ci->i_rsubdirs); + return ceph_fmt_xattr(val, size, "%lld", + ci->i_rfiles + ci->i_rsubdirs); } static ssize_t ceph_vxattrcb_dir_rfiles(struct ceph_inode_info *ci, char *val, size_t size) { - return snprintf(val, size, "%lld", ci->i_rfiles); + return ceph_fmt_xattr(val, size, "%lld", ci->i_rfiles); } static ssize_t ceph_vxattrcb_dir_rsubdirs(struct ceph_inode_info *ci, char *val, size_t size) { - return snprintf(val, size, "%lld", ci->i_rsubdirs); + return ceph_fmt_xattr(val, size, "%lld", ci->i_rsubdirs); } static ssize_t ceph_vxattrcb_dir_rbytes(struct ceph_inode_info *ci, char *val, size_t size) { - return snprintf(val, size, "%lld", ci->i_rbytes); + return ceph_fmt_xattr(val, size, "%lld", ci->i_rbytes); } static ssize_t ceph_vxattrcb_dir_rctime(struct ceph_inode_info *ci, char *val, size_t size) { - return snprintf(val, size, "%lld.%09ld", ci->i_rctime.tv_sec, - ci->i_rctime.tv_nsec); + return ceph_fmt_xattr(val, size, "%lld.%09ld", ci->i_rctime.tv_sec, + ci->i_rctime.tv_nsec); } /* dir pin */ @@ -218,7 +252,7 @@ static bool ceph_vxattrcb_dir_pin_exists(struct ceph_inode_info *ci) static ssize_t ceph_vxattrcb_dir_pin(struct ceph_inode_info *ci, char *val, size_t size) { - return snprintf(val, size, "%d", (int)ci->i_dir_pin); + return ceph_fmt_xattr(val, size, "%d", (int)ci->i_dir_pin); } /* quotas */ @@ -238,20 +272,20 @@ static bool ceph_vxattrcb_quota_exists(struct ceph_inode_info *ci) static ssize_t ceph_vxattrcb_quota(struct ceph_inode_info *ci, char *val, size_t size) { - return snprintf(val, size, "max_bytes=%llu max_files=%llu", - ci->i_max_bytes, ci->i_max_files); + return ceph_fmt_xattr(val, size, "max_bytes=%llu max_files=%llu", + ci->i_max_bytes, ci->i_max_files); } static ssize_t ceph_vxattrcb_quota_max_bytes(struct ceph_inode_info *ci, char *val, size_t size) { - return snprintf(val, size, "%llu", ci->i_max_bytes); + return ceph_fmt_xattr(val, size, "%llu", ci->i_max_bytes); } static ssize_t ceph_vxattrcb_quota_max_files(struct ceph_inode_info *ci, char *val, size_t size) { - return snprintf(val, size, "%llu", ci->i_max_files); + return ceph_fmt_xattr(val, size, "%llu", ci->i_max_files); } /* snapshots */ @@ -263,8 +297,8 @@ static bool ceph_vxattrcb_snap_btime_exists(struct ceph_inode_info *ci) static ssize_t ceph_vxattrcb_snap_btime(struct ceph_inode_info *ci, char *val, size_t size) { - return snprintf(val, size, "%lld.%09ld", ci->i_snap_btime.tv_sec, - ci->i_snap_btime.tv_nsec); + return ceph_fmt_xattr(val, size, "%lld.%09ld", ci->i_snap_btime.tv_sec, + ci->i_snap_btime.tv_nsec); } #define CEPH_XATTR_NAME(_type, _name) XATTR_CEPH_PREFIX #_type "." #_name |