After a server reboot, clients are failing to move files with ENOENT.
This is caused by DFS referrals containing multiple separators, which
the server move call doesn't recognize.
v1: Initial patch.
v2: Move prototype to header.
BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=2182472
Fixes: a31080899d5f ("cifs: sanitize multiple delimiters in prepath")
Actually-Fixes: 24e0a1eff9e2 ("cifs: switch to new mount api")
Signed-off-by: Thiago Rafael Becker <[email protected]>
---
fs/cifs/fs_context.c | 13 +++++++------
fs/cifs/fs_context.h | 3 +++
fs/cifs/misc.c | 2 +-
3 files changed, 11 insertions(+), 7 deletions(-)
diff --git a/fs/cifs/fs_context.c b/fs/cifs/fs_context.c
index 6d13f8207e96a..ace11a1a7c8ab 100644
--- a/fs/cifs/fs_context.c
+++ b/fs/cifs/fs_context.c
@@ -441,13 +441,14 @@ int smb3_parse_opt(const char *options, const char *key, char **val)
* but there are some bugs that prevent rename from working if there are
* multiple delimiters.
*
- * Returns a sanitized duplicate of @path. The caller is responsible for
- * cleaning up the original.
+ * Returns a sanitized duplicate of @path. @gfp indicates the GFP_* flags
+ * for kstrdup.
+ * The caller is responsible for freeing the original.
*/
#define IS_DELIM(c) ((c) == '/' || (c) == '\\')
-static char *sanitize_path(char *path)
+char *cifs_sanitize_prepath(char *prepath, gfp_t gfp)
{
- char *cursor1 = path, *cursor2 = path;
+ char *cursor1 = prepath, *cursor2 = prepath;
/* skip all prepended delimiters */
while (IS_DELIM(*cursor1))
@@ -469,7 +470,7 @@ static char *sanitize_path(char *path)
cursor2--;
*(cursor2) = '\0';
- return kstrdup(path, GFP_KERNEL);
+ return kstrdup(prepath, gfp);
}
/*
@@ -531,7 +532,7 @@ smb3_parse_devname(const char *devname, struct smb3_fs_context *ctx)
if (!*pos)
return 0;
- ctx->prepath = sanitize_path(pos);
+ ctx->prepath = cifs_sanitize_prepath(pos, GFP_KERNEL);
if (!ctx->prepath)
return -ENOMEM;
diff --git a/fs/cifs/fs_context.h b/fs/cifs/fs_context.h
index 3de00e7127ec4..f4eaf85589022 100644
--- a/fs/cifs/fs_context.h
+++ b/fs/cifs/fs_context.h
@@ -287,4 +287,7 @@ extern void smb3_update_mnt_flags(struct cifs_sb_info *cifs_sb);
*/
#define SMB3_MAX_DCLOSETIMEO (1 << 30)
#define SMB3_DEF_DCLOSETIMEO (1 * HZ) /* even 1 sec enough to help eg open/write/close/open/read */
+
+extern char *cifs_sanitize_prepath(char *prepath, gfp_t gfp);
+
#endif
diff --git a/fs/cifs/misc.c b/fs/cifs/misc.c
index b44fb51968bfb..7f085ed2d866b 100644
--- a/fs/cifs/misc.c
+++ b/fs/cifs/misc.c
@@ -1195,7 +1195,7 @@ int cifs_update_super_prepath(struct cifs_sb_info *cifs_sb, char *prefix)
kfree(cifs_sb->prepath);
if (prefix && *prefix) {
- cifs_sb->prepath = kstrdup(prefix, GFP_ATOMIC);
+ cifs_sb->prepath = cifs_sanitize_prepath(prefix, GFP_ATOMIC);
if (!cifs_sb->prepath)
return -ENOMEM;
--
2.39.2
Added to cifs-2.6.git for-next and updated the tag which says:
"Buglink:" to "Link:" (see this email thread for context
https://lore.kernel.org/all/3b036087d80b8c0e07a46a1dbaaf4ad0d018f8d5.1674217480.git.linux@leemhuis.info/)
On Wed, Apr 5, 2023 at 8:28 AM Thiago Becker <[email protected]> wrote:
>
> After a server reboot, clients are failing to move files with ENOENT.
> This is caused by DFS referrals containing multiple separators, which
> the server move call doesn't recognize.
>
> v1: Initial patch.
> v2: Move prototype to header.
>
> BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=2182472
> Fixes: a31080899d5f ("cifs: sanitize multiple delimiters in prepath")
> Actually-Fixes: 24e0a1eff9e2 ("cifs: switch to new mount api")
> Signed-off-by: Thiago Rafael Becker <[email protected]>
> ---
> fs/cifs/fs_context.c | 13 +++++++------
> fs/cifs/fs_context.h | 3 +++
> fs/cifs/misc.c | 2 +-
> 3 files changed, 11 insertions(+), 7 deletions(-)
>
> diff --git a/fs/cifs/fs_context.c b/fs/cifs/fs_context.c
> index 6d13f8207e96a..ace11a1a7c8ab 100644
> --- a/fs/cifs/fs_context.c
> +++ b/fs/cifs/fs_context.c
> @@ -441,13 +441,14 @@ int smb3_parse_opt(const char *options, const char *key, char **val)
> * but there are some bugs that prevent rename from working if there are
> * multiple delimiters.
> *
> - * Returns a sanitized duplicate of @path. The caller is responsible for
> - * cleaning up the original.
> + * Returns a sanitized duplicate of @path. @gfp indicates the GFP_* flags
> + * for kstrdup.
> + * The caller is responsible for freeing the original.
> */
> #define IS_DELIM(c) ((c) == '/' || (c) == '\\')
> -static char *sanitize_path(char *path)
> +char *cifs_sanitize_prepath(char *prepath, gfp_t gfp)
> {
> - char *cursor1 = path, *cursor2 = path;
> + char *cursor1 = prepath, *cursor2 = prepath;
>
> /* skip all prepended delimiters */
> while (IS_DELIM(*cursor1))
> @@ -469,7 +470,7 @@ static char *sanitize_path(char *path)
> cursor2--;
>
> *(cursor2) = '\0';
> - return kstrdup(path, GFP_KERNEL);
> + return kstrdup(prepath, gfp);
> }
>
> /*
> @@ -531,7 +532,7 @@ smb3_parse_devname(const char *devname, struct smb3_fs_context *ctx)
> if (!*pos)
> return 0;
>
> - ctx->prepath = sanitize_path(pos);
> + ctx->prepath = cifs_sanitize_prepath(pos, GFP_KERNEL);
> if (!ctx->prepath)
> return -ENOMEM;
>
> diff --git a/fs/cifs/fs_context.h b/fs/cifs/fs_context.h
> index 3de00e7127ec4..f4eaf85589022 100644
> --- a/fs/cifs/fs_context.h
> +++ b/fs/cifs/fs_context.h
> @@ -287,4 +287,7 @@ extern void smb3_update_mnt_flags(struct cifs_sb_info *cifs_sb);
> */
> #define SMB3_MAX_DCLOSETIMEO (1 << 30)
> #define SMB3_DEF_DCLOSETIMEO (1 * HZ) /* even 1 sec enough to help eg open/write/close/open/read */
> +
> +extern char *cifs_sanitize_prepath(char *prepath, gfp_t gfp);
> +
> #endif
> diff --git a/fs/cifs/misc.c b/fs/cifs/misc.c
> index b44fb51968bfb..7f085ed2d866b 100644
> --- a/fs/cifs/misc.c
> +++ b/fs/cifs/misc.c
> @@ -1195,7 +1195,7 @@ int cifs_update_super_prepath(struct cifs_sb_info *cifs_sb, char *prefix)
> kfree(cifs_sb->prepath);
>
> if (prefix && *prefix) {
> - cifs_sb->prepath = kstrdup(prefix, GFP_ATOMIC);
> + cifs_sb->prepath = cifs_sanitize_prepath(prefix, GFP_ATOMIC);
> if (!cifs_sb->prepath)
> return -ENOMEM;
>
> --
> 2.39.2
>
--
Thanks,
Steve