[PATCH 04/11] orangefs: convert strncpy() to strscpy()

Arnd Bergmann
2024-03-28T14:06:28Z

From: Arnd Bergmann <arnd@arndb.de>

gcc warns about a truncated string copy with a 255 byte string getting
copied to a buffer of the same length, losing the 0-termination:

In function 'orangefs_unmount',
inlined from 'orangefs_kill_sb' at arm-soc/fs/orangefs/super.c:619:6:
fs/orangefs/super.c:406:9: error: 'strncpy' output may be truncated copying 255 bytes from a string of length 255 [-Werror=stringop-truncation]
406 | strncpy(op->upcall.req.fs_umount.orangefs_config_server,
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
407 | devname, ORANGEFS_MAX_SERVER_ADDR_LEN - 1);
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

I see that most string copies in orangefs are for the upcalls and use
a buffer that is one short to get the implied termination from the
zero-filled buffer, but some other instances lack the '-1' part.

Convert from strncpy() to strscpy() to avoids both the warning about
the buffer size and the need for the explicit padding, since strscpy
guarantees a zero-terminated buffer.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
fs/orangefs/dcache.c | 4 ++--
fs/orangefs/namei.c | 33 +++++++++++++++------------------
fs/orangefs/super.c | 16 +++++++---------
3 files changed, 24 insertions(+), 29 deletions(-)

diff --git a/fs/orangefs/dcache.c b/fs/orangefs/dcache.c
index 8bbe9486e3a6..96ed9900f7a9 100644
--- a/fs/orangefs/dcache.c
+++ b/fs/orangefs/dcache.c
@@ -33,9 +33,9 @@ static int orangefs_revalidate_lookup(struct dentry *dentry)

new_op->upcall.req.lookup.sym_follow = ORANGEFS_LOOKUP_LINK_NO_FOLLOW;
new_op->upcall.req.lookup.parent_refn = parent->refn;
- strncpy(new_op->upcall.req.lookup.d_name,
+ strscpy(new_op->upcall.req.lookup.d_name,
dentry->d_name.name,
- ORANGEFS_NAME_MAX - 1);
+ ORANGEFS_NAME_MAX);

gossip_debug(GOSSIP_DCACHE_DEBUG,
"%s:%s:%d interrupt flag [%d]\n",
diff --git a/fs/orangefs/namei.c b/fs/orangefs/namei.c
index c9dfd5c6a097..5e46d3bdcb05 100644
--- a/fs/orangefs/namei.c
+++ b/fs/orangefs/namei.c
@@ -41,8 +41,8 @@ static int orangefs_create(struct mnt_idmap *idmap,
fill_default_sys_attrs(new_op->upcall.req.create.attributes,
ORANGEFS_TYPE_METAFILE, mode);

- strncpy(new_op->upcall.req.create.d_name,
- dentry->d_name.name, ORANGEFS_NAME_MAX - 1);
+ strscpy(new_op->upcall.req.create.d_name,
+ dentry->d_name.name, ORANGEFS_NAME_MAX);

ret = service_operation(new_op, __func__, get_interruptible_flag(dir));

@@ -137,8 +137,8 @@ static struct dentry *orangefs_lookup(struct inode *dir, struct dentry *dentry,
&parent->refn.khandle);
new_op->upcall.req.lookup.parent_refn = parent->refn;

- strncpy(new_op->upcall.req.lookup.d_name, dentry->d_name.name,
- ORANGEFS_NAME_MAX - 1);
+ strscpy(new_op->upcall.req.lookup.d_name, dentry->d_name.name,
+ ORANGEFS_NAME_MAX);

gossip_debug(GOSSIP_NAME_DEBUG,
"%s: doing lookup on %s under %pU,%d\n",
@@ -192,8 +192,8 @@ static int orangefs_unlink(struct inode *dir, struct dentry *dentry)
return -ENOMEM;

new_op->upcall.req.remove.parent_refn = parent->refn;
- strncpy(new_op->upcall.req.remove.d_name, dentry->d_name.name,
- ORANGEFS_NAME_MAX - 1);
+ strscpy(new_op->upcall.req.remove.d_name, dentry->d_name.name,
+ ORANGEFS_NAME_MAX);

ret = service_operation(new_op, "orangefs_unlink",
get_interruptible_flag(inode));
@@ -247,10 +247,9 @@ static int orangefs_symlink(struct mnt_idmap *idmap,
ORANGEFS_TYPE_SYMLINK,
mode);

- strncpy(new_op->upcall.req.sym.entry_name,
- dentry->d_name.name,
- ORANGEFS_NAME_MAX - 1);
- strncpy(new_op->upcall.req.sym.target, symname, ORANGEFS_NAME_MAX - 1);
+ strscpy(new_op->upcall.req.sym.entry_name,
+ dentry->d_name.name, ORANGEFS_NAME_MAX);
+ strscpy(new_op->upcall.req.sym.target, symname, ORANGEFS_NAME_MAX);

ret = service_operation(new_op, __func__, get_interruptible_flag(dir));

@@ -324,8 +323,8 @@ static int orangefs_mkdir(struct mnt_idmap *idmap, struct inode *dir,
fill_default_sys_attrs(new_op->upcall.req.mkdir.attributes,
ORANGEFS_TYPE_DIRECTORY, mode);

- strncpy(new_op->upcall.req.mkdir.d_name,
- dentry->d_name.name, ORANGEFS_NAME_MAX - 1);
+ strscpy(new_op->upcall.req.mkdir.d_name,
+ dentry->d_name.name, ORANGEFS_NAME_MAX);

ret = service_operation(new_op, __func__, get_interruptible_flag(dir));

@@ -405,12 +404,10 @@ static int orangefs_rename(struct mnt_idmap *idmap,
new_op->upcall.req.rename.old_parent_refn = ORANGEFS_I(old_dir)->refn;
new_op->upcall.req.rename.new_parent_refn = ORANGEFS_I(new_dir)->refn;

- strncpy(new_op->upcall.req.rename.d_old_name,
- old_dentry->d_name.name,
- ORANGEFS_NAME_MAX - 1);
- strncpy(new_op->upcall.req.rename.d_new_name,
- new_dentry->d_name.name,
- ORANGEFS_NAME_MAX - 1);
+ strscpy(new_op->upcall.req.rename.d_old_name,
+ old_dentry->d_name.name, ORANGEFS_NAME_MAX);
+ strscpy(new_op->upcall.req.rename.d_new_name,
+ new_dentry->d_name.name, ORANGEFS_NAME_MAX);

ret = service_operation(new_op,
"orangefs_rename",
diff --git a/fs/orangefs/super.c b/fs/orangefs/super.c
index d990f4356b30..c714380ab38b 100644
--- a/fs/orangefs/super.c
+++ b/fs/orangefs/super.c
@@ -256,7 +256,7 @@ int orangefs_remount(struct orangefs_sb_info_s *orangefs_sb)
new_op = op_alloc(ORANGEFS_VFS_OP_FS_MOUNT);
if (!new_op)
return -ENOMEM;
- strncpy(new_op->upcall.req.fs_mount.orangefs_config_server,
+ strscpy(new_op->upcall.req.fs_mount.orangefs_config_server,
orangefs_sb->devname,
ORANGEFS_MAX_SERVER_ADDR_LEN);

@@ -403,8 +403,8 @@ static int orangefs_unmount(int id, __s32 fs_id, const char *devname)
return -ENOMEM;
op->upcall.req.fs_umount.id = id;
op->upcall.req.fs_umount.fs_id = fs_id;
- strncpy(op->upcall.req.fs_umount.orangefs_config_server,
- devname, ORANGEFS_MAX_SERVER_ADDR_LEN - 1);
+ strscpy(op->upcall.req.fs_umount.orangefs_config_server,
+ devname, ORANGEFS_MAX_SERVER_ADDR_LEN);
r = service_operation(op, "orangefs_fs_umount", 0);
/* Not much to do about an error here. */
if (r)
@@ -497,9 +497,8 @@ struct dentry *orangefs_mount(struct file_system_type *fst,
if (!new_op)
return ERR_PTR(-ENOMEM);

- strncpy(new_op->upcall.req.fs_mount.orangefs_config_server,
- devname,
- ORANGEFS_MAX_SERVER_ADDR_LEN - 1);
+ strscpy(new_op->upcall.req.fs_mount.orangefs_config_server,
+ devname, ORANGEFS_MAX_SERVER_ADDR_LEN);

gossip_debug(GOSSIP_SUPER_DEBUG,
"Attempting ORANGEFS Mount via host %s\n",
@@ -546,9 +545,8 @@ struct dentry *orangefs_mount(struct file_system_type *fst,
* on successful mount, store the devname and data
* used
*/
- strncpy(ORANGEFS_SB(sb)->devname,
- devname,
- ORANGEFS_MAX_SERVER_ADDR_LEN - 1);
+ strscpy(ORANGEFS_SB(sb)->devname, devname,
+ ORANGEFS_MAX_SERVER_ADDR_LEN);

/* mount_pending must be cleared */
ORANGEFS_SB(sb)->mount_pending = 0;
--
2.39.2