diff mbox series

[v3,3/7] fsstress: add operation for setting xattrs on files and directories

Message ID 20190404163018.19129-1-fdmanana@kernel.org (mailing list archive)
State New, archived
Headers show
Series [v3,1/7] fsstress: allow fsync on directories too | expand

Commit Message

Filipe Manana April 4, 2019, 4:30 p.m. UTC 
From: Filipe Manana <fdmanana@suse.com>

Currently fsstress does not exercise creating, reading or deleting xattrs
on files or directories. This change adds support for setting xattrs on
files and directories, using only the xattr user namespace (the other
namespaces are not general purpose and are used for security, capabilities,
ACLs, etc). This adds a counter for each file entry structure that keeps
track of the number of xattrs set for the file entry, and each new xattr
has a name that includes the counter's value (example: "user.x4").
Values for the xattrs have at most 100 bytes, which is more than the
maximum size supported for all major filesystems.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
---

V2: Use a different name for the operation (setfattr instead of the already
    taken setxattr) and make use of the helper functions for opening and
    closing files or directories, introduced in the first patch of this
    series.
V3: Simplified implementation to not need to open a file descriptor and
    use a path string instead.

 ltp/fsstress.c | 140 +++++++++++++++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 131 insertions(+), 9 deletions(-)

Comments

Eryu Guan April 19, 2019, 7:12 a.m. UTC | #1 
On Thu, Apr 04, 2019 at 05:30:18PM +0100, fdmanana@kernel.org wrote:
> From: Filipe Manana <fdmanana@suse.com>
> 
> Currently fsstress does not exercise creating, reading or deleting xattrs
> on files or directories. This change adds support for setting xattrs on
> files and directories, using only the xattr user namespace (the other
> namespaces are not general purpose and are used for security, capabilities,
> ACLs, etc). This adds a counter for each file entry structure that keeps
> track of the number of xattrs set for the file entry, and each new xattr
> has a name that includes the counter's value (example: "user.x4").
> Values for the xattrs have at most 100 bytes, which is more than the
> maximum size supported for all major filesystems.
> 
> Signed-off-by: Filipe Manana <fdmanana@suse.com>

I've went through the xattr patches, and they look good to me overall,
thanks! Just some minor comments in this patch below.

> ---
> 
> V2: Use a different name for the operation (setfattr instead of the already
>     taken setxattr) and make use of the helper functions for opening and
>     closing files or directories, introduced in the first patch of this
>     series.
> V3: Simplified implementation to not need to open a file descriptor and
>     use a path string instead.
> 
>  ltp/fsstress.c | 140 +++++++++++++++++++++++++++++++++++++++++++++++++++++----
>  1 file changed, 131 insertions(+), 9 deletions(-)
> 
> diff --git a/ltp/fsstress.c b/ltp/fsstress.c
> index 3ec19143..d1db19da 100644
> --- a/ltp/fsstress.c
> +++ b/ltp/fsstress.c
> @@ -27,6 +27,7 @@
>  io_context_t	io_ctx;
>  #endif
>  #include <sys/syscall.h>
> +#include <sys/xattr.h>
>  
>  #ifndef FS_IOC_GETFLAGS
>  #define FS_IOC_GETFLAGS                 _IOR('f', 1, long)
> @@ -84,6 +85,7 @@ typedef enum {
>  	OP_RESVSP,
>  	OP_RMDIR,
>  	OP_SETATTR,
> +	OP_SETFATTR,
>  	OP_SETXATTR,

I think it'd be better to document above three *ATTR operations in
comments.

>  	OP_SPLICE,
>  	OP_STAT,
> @@ -110,6 +112,7 @@ typedef struct opdesc {
>  typedef struct fent {
>  	int	id;
>  	int	parent;
> +	int	xattr_counter;
>  } fent_t;
>  
>  typedef struct flist {
> @@ -156,6 +159,8 @@ struct print_string {
>  #define	MAXFSIZE	((1ULL << 63) - 1ULL)
>  #define	MAXFSIZE32	((1ULL << 40) - 1ULL)
>  
> +#define XATTR_NAME_BUF_SIZE 18
> +
>  void	afsync_f(int, long);
>  void	allocsp_f(int, long);
>  void	aread_f(int, long);
> @@ -176,6 +181,7 @@ void	fdatasync_f(int, long);
>  void	fiemap_f(int, long);
>  void	freesp_f(int, long);
>  void	fsync_f(int, long);
> +char	*gen_random_string(int);
>  void	getattr_f(int, long);
>  void	getdents_f(int, long);
>  void	link_f(int, long);
> @@ -194,6 +200,7 @@ void	rename_f(int, long);
>  void	resvsp_f(int, long);
>  void	rmdir_f(int, long);
>  void	setattr_f(int, long);
> +void	setfattr_f(int, long);
>  void	setxattr_f(int, long);
>  void	splice_f(int, long);
>  void	stat_f(int, long);
> @@ -204,6 +211,7 @@ void	unlink_f(int, long);
>  void	unresvsp_f(int, long);
>  void	write_f(int, long);
>  void	writev_f(int, long);
> +char	*xattr_flag_to_string(int);
>  
>  opdesc_t	ops[] = {
>       /* { OP_ENUM, "name", function, freq, iswrite }, */
> @@ -245,6 +253,7 @@ opdesc_t	ops[] = {
>  	{ OP_RESVSP, "resvsp", resvsp_f, 1, 1 },
>  	{ OP_RMDIR, "rmdir", rmdir_f, 1, 1 },
>  	{ OP_SETATTR, "setattr", setattr_f, 0, 1 },
> +	{ OP_SETFATTR, "setfattr", setfattr_f, 4, 1 },

The frequency of setfattr looks a bit high to me, a buffer "write" op
has 4. Maybe 2 is more reasonable and change get/delfattr op's freq to 1?

(And rename delfattr to removefattr to match the removexattr syscall
name?)

>  	{ OP_SETXATTR, "setxattr", setxattr_f, 1, 1 },
>  	{ OP_SPLICE, "splice", splice_f, 1, 1 },
>  	{ OP_STAT, "stat", stat_f, 1, 0 },
> @@ -296,7 +305,7 @@ char		*execute_cmd = NULL;
>  int		execute_freq = 1;
>  struct print_string	flag_str = {0};
>  
> -void	add_to_flist(int, int, int);
> +void	add_to_flist(int, int, int, int);
>  void	append_pathname(pathname_t *, char *);
>  int	attr_list_path(pathname_t *, char *, const int, int, attrlist_cursor_t *);
>  int	attr_remove_path(pathname_t *, const char *, int);
> @@ -315,6 +324,7 @@ int	fent_to_name(pathname_t *, flist_t *, fent_t *);
>  void	fix_parent(int, int);
>  void	free_pathname(pathname_t *);
>  int	generate_fname(fent_t *, int, pathname_t *, int *, int *);
> +void	generate_xattr_name(int, char *);
>  int	get_fname(int, long, pathname_t *, flist_t **, fent_t **, int *);
>  void	init_pathname(pathname_t *);
>  int	lchown_path(pathname_t *, uid_t, gid_t);
> @@ -716,7 +726,7 @@ translate_flags(int flags, const char *delim,
>  }
>  
>  void
> -add_to_flist(int ft, int id, int parent)
> +add_to_flist(int ft, int id, int parent, int xattr_counter)
>  {
>  	fent_t	*fep;
>  	flist_t	*ftp;
> @@ -729,6 +739,7 @@ add_to_flist(int ft, int id, int parent)
>  	fep = &ftp->fents[ftp->nfiles++];
>  	fep->id = id;
>  	fep->parent = parent;
> +	fep->xattr_counter = xattr_counter;
>  }
>  
>  void
> @@ -1122,6 +1133,12 @@ generate_fname(fent_t *fep, int ft, pathname_t *name, int *idp, int *v)
>  	return 1;
>  }
>  
> +void generate_xattr_name(int xattr_num, char *buffer)
> +{
> +	memcpy(buffer, "user.x", 6);
> +	sprintf(buffer + 6, "%d", xattr_num);

I think it's better to pass the buffer length too and check against it
to avoid buffer overflow.

Thanks,
Eryu

> +}
> +
>  /*
>   * Get file 
>   * Input: "which" to choose the file-types eg. non-directory
> @@ -3030,7 +3047,7 @@ creat_f(int opno, long r)
>  			if (xfsctl(f.path, fd, XFS_IOC_FSSETXATTR, &a) < 0)
>  				e1 = errno;
>  		}
> -		add_to_flist(type, id, parid);
> +		add_to_flist(type, id, parid, 0);
>  		close(fd);
>  	}
>  	if (v) {
> @@ -3495,6 +3512,28 @@ fsync_f(int opno, long r)
>  	close(fd);
>  }
>  
> +char *
> +gen_random_string(int len)
> +{
> +	static const char charset[] = "0123456789"
> +		"abcdefghijklmnopqrstuvwxyz"
> +		"ABCDEFGHIJKLMNOPQRSTUVWXYZ";
> +	int i;
> +	char *s;
> +
> +	if (len == 0)
> +		return NULL;
> +
> +	s = malloc(len);
> +	if (!s)
> +		return NULL;
> +
> +	for (i = 0; i < len; i++)
> +		s[i] = charset[random() % sizeof(charset)];
> +
> +	return s;
> +}
> +
>  void
>  getattr_f(int opno, long r)
>  {
> @@ -3551,6 +3590,7 @@ link_f(int opno, long r)
>  	int		e;
>  	pathname_t	f;
>  	fent_t		*fep;
> +	fent_t		*fep_src;
>  	flist_t		*flp;
>  	int		id;
>  	pathname_t	l;
> @@ -3559,7 +3599,7 @@ link_f(int opno, long r)
>  	int		v1;
>  
>  	init_pathname(&f);
> -	if (!get_fname(FT_NOTDIR, r, &f, &flp, NULL, &v1)) {
> +	if (!get_fname(FT_NOTDIR, r, &f, &flp, &fep_src, &v1)) {
>  		if (v1)
>  			printf("%d/%d: link - no file\n", procid, opno);
>  		free_pathname(&f);
> @@ -3586,7 +3626,7 @@ link_f(int opno, long r)
>  	e = link_path(&f, &l) < 0 ? errno : 0;
>  	check_cwd();
>  	if (e == 0)
> -		add_to_flist(flp - flist, id, parid);
> +		add_to_flist(flp - flist, id, parid, fep_src->xattr_counter);
>  	if (v) {
>  		printf("%d/%d: link %s %s %d\n", procid, opno, f.path, l.path,
>  			e);
> @@ -3626,7 +3666,7 @@ mkdir_f(int opno, long r)
>  	e = mkdir_path(&f, 0777) < 0 ? errno : 0;
>  	check_cwd();
>  	if (e == 0)
> -		add_to_flist(FT_DIR, id, parid);
> +		add_to_flist(FT_DIR, id, parid, 0);
>  	if (v) {
>  		printf("%d/%d: mkdir %s %d\n", procid, opno, f.path, e);
>  		printf("%d/%d: mkdir add id=%d,parent=%d\n", procid, opno, id, parid);
> @@ -3664,7 +3704,7 @@ mknod_f(int opno, long r)
>  	e = mknod_path(&f, S_IFCHR|0444, 0) < 0 ? errno : 0;
>  	check_cwd();
>  	if (e == 0)
> -		add_to_flist(FT_DEV, id, parid);
> +		add_to_flist(FT_DEV, id, parid, 0);
>  	if (v) {
>  		printf("%d/%d: mknod %s %d\n", procid, opno, f.path, e);
>  		printf("%d/%d: mknod add id=%d,parent=%d\n", procid, opno, id, parid);
> @@ -4040,12 +4080,14 @@ rename_f(int opno, long r)
>  	e = rename_path(&f, &newf) < 0 ? errno : 0;
>  	check_cwd();
>  	if (e == 0) {
> +		int xattr_counter = fep->xattr_counter;
> +
>  		if (flp - flist == FT_DIR) {
>  			oldid = fep->id;
>  			fix_parent(oldid, id);
>  		}
>  		del_from_flist(flp - flist, fep - flp->fents);
> -		add_to_flist(flp - flist, id, parid);
> +		add_to_flist(flp - flist, id, parid, xattr_counter);
>  	}
>  	if (v) {
>  		printf("%d/%d: rename %s to %s %d\n", procid, opno, f.path,
> @@ -4168,6 +4210,76 @@ setattr_f(int opno, long r)
>  }
>  
>  void
> +setfattr_f(int opno, long r)
> +{
> +	int		e;
> +	pathname_t	f;
> +	fent_t	        *fep;
> +	int		v;
> +	int             value_len;
> +	char            name[XATTR_NAME_BUF_SIZE];
> +	char            *value = NULL;
> +	int             flag = 0;
> +	int             xattr_num;
> +
> +	init_pathname(&f);
> +	if (!get_fname(FT_REGFILE | FT_DIRm, r, &f, NULL, &fep, &v)) {
> +		if (v)
> +			printf("%d/%d: setfattr - no filename\n", procid, opno);
> +		goto out;
> +	}
> +	check_cwd();
> +
> +	if ((fep->xattr_counter > 0) && (random() % 2)) {
> +		/*
> +		 * Use an existing xattr name for replacing its value or
> +		 * create again a xattr that was previously deleted.
> +		 */
> +		xattr_num = (random() % fep->xattr_counter) + 1;
> +		if (random() % 2)
> +			flag = XATTR_REPLACE;
> +	} else {
> +		/* Use a new xattr name. */
> +		xattr_num = fep->xattr_counter + 1;
> +		/*
> +		 * Don't always use the create flag because even if our xattr
> +		 * counter is 0, we may still have xattrs associated to this
> +		 * file (this happens when xattrs are added to a file through
> +		 * one of its other hard links), so we can end up updating an
> +		 * existing xattr too.
> +		 */
> +		if (random() % 2)
> +			flag = XATTR_CREATE;
> +	}
> +
> +	/*
> +	 * The maximum supported value size depends on the filesystem
> +	 * implementation, but 100 bytes is a safe value for most filesystems
> +	 * at least.
> +	 */
> +	value_len = random() % 101;
> +	value = gen_random_string(value_len);
> +	if (!value && value_len > 0) {
> +		if (v)
> +			printf("%d/%d: setfattr - file %s failed to allocate value with %d bytes\n",
> +			       procid, opno, f.path, value_len);
> +		goto out;
> +	}
> +	generate_xattr_name(xattr_num, name);
> +
> +	e = setxattr(f.path, name, value, value_len, flag) < 0 ? errno : 0;
> +	if (e == 0)
> +		fep->xattr_counter++;
> +	if (v)
> +		printf("%d/%d: setfattr file %s name %s flag %s value length %d: %d\n",
> +		       procid, opno, f.path, name, xattr_flag_to_string(flag),
> +		       value_len, e);
> +out:
> +	free(value);
> +	free_pathname(&f);
> +}
> +
> +void
>  stat_f(int opno, long r)
>  {
>  	int		e;
> @@ -4229,7 +4341,7 @@ symlink_f(int opno, long r)
>  	e = symlink_path(val, &f) < 0 ? errno : 0;
>  	check_cwd();
>  	if (e == 0)
> -		add_to_flist(FT_SYM, id, parid);
> +		add_to_flist(FT_SYM, id, parid, 0);
>  	free(val);
>  	if (v) {
>  		printf("%d/%d: symlink %s %d\n", procid, opno, f.path, e);
> @@ -4498,3 +4610,13 @@ writev_f(int opno, long r)
>  	free_pathname(&f);
>  	close(fd);
>  }
> +
> +char *
> +xattr_flag_to_string(int flag)
> +{
> +	if (flag == XATTR_CREATE)
> +		return "create";
> +	if (flag == XATTR_REPLACE)
> +		return "replace";
> +	return "none";
> +}
> -- 
> 2.11.0
>
diff mbox series

Patch

diff --git a/ltp/fsstress.c b/ltp/fsstress.c
index 3ec19143..d1db19da 100644
--- a/ltp/fsstress.c
+++ b/ltp/fsstress.c
@@ -27,6 +27,7 @@ 
 io_context_t	io_ctx;
 #endif
 #include <sys/syscall.h>
+#include <sys/xattr.h>
 
 #ifndef FS_IOC_GETFLAGS
 #define FS_IOC_GETFLAGS                 _IOR('f', 1, long)
@@ -84,6 +85,7 @@  typedef enum {
 	OP_RESVSP,
 	OP_RMDIR,
 	OP_SETATTR,
+	OP_SETFATTR,
 	OP_SETXATTR,
 	OP_SPLICE,
 	OP_STAT,
@@ -110,6 +112,7 @@  typedef struct opdesc {
 typedef struct fent {
 	int	id;
 	int	parent;
+	int	xattr_counter;
 } fent_t;
 
 typedef struct flist {
@@ -156,6 +159,8 @@  struct print_string {
 #define	MAXFSIZE	((1ULL << 63) - 1ULL)
 #define	MAXFSIZE32	((1ULL << 40) - 1ULL)
 
+#define XATTR_NAME_BUF_SIZE 18
+
 void	afsync_f(int, long);
 void	allocsp_f(int, long);
 void	aread_f(int, long);
@@ -176,6 +181,7 @@  void	fdatasync_f(int, long);
 void	fiemap_f(int, long);
 void	freesp_f(int, long);
 void	fsync_f(int, long);
+char	*gen_random_string(int);
 void	getattr_f(int, long);
 void	getdents_f(int, long);
 void	link_f(int, long);
@@ -194,6 +200,7 @@  void	rename_f(int, long);
 void	resvsp_f(int, long);
 void	rmdir_f(int, long);
 void	setattr_f(int, long);
+void	setfattr_f(int, long);
 void	setxattr_f(int, long);
 void	splice_f(int, long);
 void	stat_f(int, long);
@@ -204,6 +211,7 @@  void	unlink_f(int, long);
 void	unresvsp_f(int, long);
 void	write_f(int, long);
 void	writev_f(int, long);
+char	*xattr_flag_to_string(int);
 
 opdesc_t	ops[] = {
      /* { OP_ENUM, "name", function, freq, iswrite }, */
@@ -245,6 +253,7 @@  opdesc_t	ops[] = {
 	{ OP_RESVSP, "resvsp", resvsp_f, 1, 1 },
 	{ OP_RMDIR, "rmdir", rmdir_f, 1, 1 },
 	{ OP_SETATTR, "setattr", setattr_f, 0, 1 },
+	{ OP_SETFATTR, "setfattr", setfattr_f, 4, 1 },
 	{ OP_SETXATTR, "setxattr", setxattr_f, 1, 1 },
 	{ OP_SPLICE, "splice", splice_f, 1, 1 },
 	{ OP_STAT, "stat", stat_f, 1, 0 },
@@ -296,7 +305,7 @@  char		*execute_cmd = NULL;
 int		execute_freq = 1;
 struct print_string	flag_str = {0};
 
-void	add_to_flist(int, int, int);
+void	add_to_flist(int, int, int, int);
 void	append_pathname(pathname_t *, char *);
 int	attr_list_path(pathname_t *, char *, const int, int, attrlist_cursor_t *);
 int	attr_remove_path(pathname_t *, const char *, int);
@@ -315,6 +324,7 @@  int	fent_to_name(pathname_t *, flist_t *, fent_t *);
 void	fix_parent(int, int);
 void	free_pathname(pathname_t *);
 int	generate_fname(fent_t *, int, pathname_t *, int *, int *);
+void	generate_xattr_name(int, char *);
 int	get_fname(int, long, pathname_t *, flist_t **, fent_t **, int *);
 void	init_pathname(pathname_t *);
 int	lchown_path(pathname_t *, uid_t, gid_t);
@@ -716,7 +726,7 @@  translate_flags(int flags, const char *delim,
 }
 
 void
-add_to_flist(int ft, int id, int parent)
+add_to_flist(int ft, int id, int parent, int xattr_counter)
 {
 	fent_t	*fep;
 	flist_t	*ftp;
@@ -729,6 +739,7 @@  add_to_flist(int ft, int id, int parent)
 	fep = &ftp->fents[ftp->nfiles++];
 	fep->id = id;
 	fep->parent = parent;
+	fep->xattr_counter = xattr_counter;
 }
 
 void
@@ -1122,6 +1133,12 @@  generate_fname(fent_t *fep, int ft, pathname_t *name, int *idp, int *v)
 	return 1;
 }
 
+void generate_xattr_name(int xattr_num, char *buffer)
+{
+	memcpy(buffer, "user.x", 6);
+	sprintf(buffer + 6, "%d", xattr_num);
+}
+
 /*
  * Get file 
  * Input: "which" to choose the file-types eg. non-directory
@@ -3030,7 +3047,7 @@  creat_f(int opno, long r)
 			if (xfsctl(f.path, fd, XFS_IOC_FSSETXATTR, &a) < 0)
 				e1 = errno;
 		}
-		add_to_flist(type, id, parid);
+		add_to_flist(type, id, parid, 0);
 		close(fd);
 	}
 	if (v) {
@@ -3495,6 +3512,28 @@  fsync_f(int opno, long r)
 	close(fd);
 }
 
+char *
+gen_random_string(int len)
+{
+	static const char charset[] = "0123456789"
+		"abcdefghijklmnopqrstuvwxyz"
+		"ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+	int i;
+	char *s;
+
+	if (len == 0)
+		return NULL;
+
+	s = malloc(len);
+	if (!s)
+		return NULL;
+
+	for (i = 0; i < len; i++)
+		s[i] = charset[random() % sizeof(charset)];
+
+	return s;
+}
+
 void
 getattr_f(int opno, long r)
 {
@@ -3551,6 +3590,7 @@  link_f(int opno, long r)
 	int		e;
 	pathname_t	f;
 	fent_t		*fep;
+	fent_t		*fep_src;
 	flist_t		*flp;
 	int		id;
 	pathname_t	l;
@@ -3559,7 +3599,7 @@  link_f(int opno, long r)
 	int		v1;
 
 	init_pathname(&f);
-	if (!get_fname(FT_NOTDIR, r, &f, &flp, NULL, &v1)) {
+	if (!get_fname(FT_NOTDIR, r, &f, &flp, &fep_src, &v1)) {
 		if (v1)
 			printf("%d/%d: link - no file\n", procid, opno);
 		free_pathname(&f);
@@ -3586,7 +3626,7 @@  link_f(int opno, long r)
 	e = link_path(&f, &l) < 0 ? errno : 0;
 	check_cwd();
 	if (e == 0)
-		add_to_flist(flp - flist, id, parid);
+		add_to_flist(flp - flist, id, parid, fep_src->xattr_counter);
 	if (v) {
 		printf("%d/%d: link %s %s %d\n", procid, opno, f.path, l.path,
 			e);
@@ -3626,7 +3666,7 @@  mkdir_f(int opno, long r)
 	e = mkdir_path(&f, 0777) < 0 ? errno : 0;
 	check_cwd();
 	if (e == 0)
-		add_to_flist(FT_DIR, id, parid);
+		add_to_flist(FT_DIR, id, parid, 0);
 	if (v) {
 		printf("%d/%d: mkdir %s %d\n", procid, opno, f.path, e);
 		printf("%d/%d: mkdir add id=%d,parent=%d\n", procid, opno, id, parid);
@@ -3664,7 +3704,7 @@  mknod_f(int opno, long r)
 	e = mknod_path(&f, S_IFCHR|0444, 0) < 0 ? errno : 0;
 	check_cwd();
 	if (e == 0)
-		add_to_flist(FT_DEV, id, parid);
+		add_to_flist(FT_DEV, id, parid, 0);
 	if (v) {
 		printf("%d/%d: mknod %s %d\n", procid, opno, f.path, e);
 		printf("%d/%d: mknod add id=%d,parent=%d\n", procid, opno, id, parid);
@@ -4040,12 +4080,14 @@  rename_f(int opno, long r)
 	e = rename_path(&f, &newf) < 0 ? errno : 0;
 	check_cwd();
 	if (e == 0) {
+		int xattr_counter = fep->xattr_counter;
+
 		if (flp - flist == FT_DIR) {
 			oldid = fep->id;
 			fix_parent(oldid, id);
 		}
 		del_from_flist(flp - flist, fep - flp->fents);
-		add_to_flist(flp - flist, id, parid);
+		add_to_flist(flp - flist, id, parid, xattr_counter);
 	}
 	if (v) {
 		printf("%d/%d: rename %s to %s %d\n", procid, opno, f.path,
@@ -4168,6 +4210,76 @@  setattr_f(int opno, long r)
 }
 
 void
+setfattr_f(int opno, long r)
+{
+	int		e;
+	pathname_t	f;
+	fent_t	        *fep;
+	int		v;
+	int             value_len;
+	char            name[XATTR_NAME_BUF_SIZE];
+	char            *value = NULL;
+	int             flag = 0;
+	int             xattr_num;
+
+	init_pathname(&f);
+	if (!get_fname(FT_REGFILE | FT_DIRm, r, &f, NULL, &fep, &v)) {
+		if (v)
+			printf("%d/%d: setfattr - no filename\n", procid, opno);
+		goto out;
+	}
+	check_cwd();
+
+	if ((fep->xattr_counter > 0) && (random() % 2)) {
+		/*
+		 * Use an existing xattr name for replacing its value or
+		 * create again a xattr that was previously deleted.
+		 */
+		xattr_num = (random() % fep->xattr_counter) + 1;
+		if (random() % 2)
+			flag = XATTR_REPLACE;
+	} else {
+		/* Use a new xattr name. */
+		xattr_num = fep->xattr_counter + 1;
+		/*
+		 * Don't always use the create flag because even if our xattr
+		 * counter is 0, we may still have xattrs associated to this
+		 * file (this happens when xattrs are added to a file through
+		 * one of its other hard links), so we can end up updating an
+		 * existing xattr too.
+		 */
+		if (random() % 2)
+			flag = XATTR_CREATE;
+	}
+
+	/*
+	 * The maximum supported value size depends on the filesystem
+	 * implementation, but 100 bytes is a safe value for most filesystems
+	 * at least.
+	 */
+	value_len = random() % 101;
+	value = gen_random_string(value_len);
+	if (!value && value_len > 0) {
+		if (v)
+			printf("%d/%d: setfattr - file %s failed to allocate value with %d bytes\n",
+			       procid, opno, f.path, value_len);
+		goto out;
+	}
+	generate_xattr_name(xattr_num, name);
+
+	e = setxattr(f.path, name, value, value_len, flag) < 0 ? errno : 0;
+	if (e == 0)
+		fep->xattr_counter++;
+	if (v)
+		printf("%d/%d: setfattr file %s name %s flag %s value length %d: %d\n",
+		       procid, opno, f.path, name, xattr_flag_to_string(flag),
+		       value_len, e);
+out:
+	free(value);
+	free_pathname(&f);
+}
+
+void
 stat_f(int opno, long r)
 {
 	int		e;
@@ -4229,7 +4341,7 @@  symlink_f(int opno, long r)
 	e = symlink_path(val, &f) < 0 ? errno : 0;
 	check_cwd();
 	if (e == 0)
-		add_to_flist(FT_SYM, id, parid);
+		add_to_flist(FT_SYM, id, parid, 0);
 	free(val);
 	if (v) {
 		printf("%d/%d: symlink %s %d\n", procid, opno, f.path, e);
@@ -4498,3 +4610,13 @@  writev_f(int opno, long r)
 	free_pathname(&f);
 	close(fd);
 }
+
+char *
+xattr_flag_to_string(int flag)
+{
+	if (flag == XATTR_CREATE)
+		return "create";
+	if (flag == XATTR_REPLACE)
+		return "replace";
+	return "none";
+}