| Message ID | 20190110170444.30616-11-amir73il@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | fanotify: add support for more event types | expand |
Hi Amir,
I love your patch! Perhaps something to improve:
[auto build test WARNING on linus/master]
[also build test WARNING on v5.0-rc1 next-20190110]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/Amir-Goldstein/fanotify-add-support-for-more-event-types/20190111-090241
config: mips-loongson1c_defconfig (attached as .config)
compiler: mipsel-linux-gnu-gcc (Debian 7.2.0-11) 7.2.0
reproduce:
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
GCC_VERSION=7.2.0 make.cross ARCH=mips
All warnings (new ones prefixed by >>):
In file included from include/linux/kernel.h:14:0,
from include/linux/list.h:9,
from include/linux/wait.h:7,
from include/linux/wait_bit.h:8,
from include/linux/fs.h:6,
from fs/notify/mark.c:76:
fs/notify/mark.c: In function 'fsnotify_add_mark_list':
>> include/linux/kern_levels.h:5:18: warning: format '%x' expects argument of type 'unsigned int', but argument 4 has type 'long int' [-Wformat=]
#define KERN_SOH "\001" /* ASCII Start Of Header */
^
include/linux/printk.h:424:10: note: in definition of macro 'printk_ratelimited'
printk(fmt, ##__VA_ARGS__); \
^~~
include/linux/kern_levels.h:12:22: note: in expansion of macro 'KERN_SOH'
#define KERN_WARNING KERN_SOH "4" /* warning conditions */
^~~~~~~~
include/linux/printk.h:440:21: note: in expansion of macro 'KERN_WARNING'
printk_ratelimited(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
^~~~~~~~~~~~
>> fs/notify/mark.c:587:3: note: in expansion of macro 'pr_warn_ratelimited'
pr_warn_ratelimited("%s: fsid mismatch on object of type %u: %x.%x != %x.%x\n",
^~~~~~~~~~~~~~~~~~~
fs/notify/mark.c:587:65: note: format string is defined here
pr_warn_ratelimited("%s: fsid mismatch on object of type %u: %x.%x != %x.%x\n",
~^
%lx
In file included from include/linux/kernel.h:14:0,
from include/linux/list.h:9,
from include/linux/wait.h:7,
from include/linux/wait_bit.h:8,
from include/linux/fs.h:6,
from fs/notify/mark.c:76:
include/linux/kern_levels.h:5:18: warning: format '%x' expects argument of type 'unsigned int', but argument 5 has type 'long int' [-Wformat=]
#define KERN_SOH "\001" /* ASCII Start Of Header */
^
include/linux/printk.h:424:10: note: in definition of macro 'printk_ratelimited'
printk(fmt, ##__VA_ARGS__); \
^~~
include/linux/kern_levels.h:12:22: note: in expansion of macro 'KERN_SOH'
#define KERN_WARNING KERN_SOH "4" /* warning conditions */
^~~~~~~~
include/linux/printk.h:440:21: note: in expansion of macro 'KERN_WARNING'
printk_ratelimited(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
^~~~~~~~~~~~
>> fs/notify/mark.c:587:3: note: in expansion of macro 'pr_warn_ratelimited'
pr_warn_ratelimited("%s: fsid mismatch on object of type %u: %x.%x != %x.%x\n",
^~~~~~~~~~~~~~~~~~~
fs/notify/mark.c:587:68: note: format string is defined here
pr_warn_ratelimited("%s: fsid mismatch on object of type %u: %x.%x != %x.%x\n",
~^
%lx
In file included from include/linux/kernel.h:14:0,
from include/linux/list.h:9,
from include/linux/wait.h:7,
from include/linux/wait_bit.h:8,
from include/linux/fs.h:6,
from fs/notify/mark.c:76:
include/linux/kern_levels.h:5:18: warning: format '%x' expects argument of type 'unsigned int', but argument 6 has type 'long int' [-Wformat=]
#define KERN_SOH "\001" /* ASCII Start Of Header */
^
include/linux/printk.h:424:10: note: in definition of macro 'printk_ratelimited'
printk(fmt, ##__VA_ARGS__); \
^~~
include/linux/kern_levels.h:12:22: note: in expansion of macro 'KERN_SOH'
#define KERN_WARNING KERN_SOH "4" /* warning conditions */
^~~~~~~~
include/linux/printk.h:440:21: note: in expansion of macro 'KERN_WARNING'
printk_ratelimited(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
^~~~~~~~~~~~
>> fs/notify/mark.c:587:3: note: in expansion of macro 'pr_warn_ratelimited'
pr_warn_ratelimited("%s: fsid mismatch on object of type %u: %x.%x != %x.%x\n",
^~~~~~~~~~~~~~~~~~~
fs/notify/mark.c:587:74: note: format string is defined here
pr_warn_ratelimited("%s: fsid mismatch on object of type %u: %x.%x != %x.%x\n",
~^
%lx
In file included from include/linux/kernel.h:14:0,
from include/linux/list.h:9,
from include/linux/wait.h:7,
from include/linux/wait_bit.h:8,
from include/linux/fs.h:6,
from fs/notify/mark.c:76:
include/linux/kern_levels.h:5:18: warning: format '%x' expects argument of type 'unsigned int', but argument 7 has type 'long int' [-Wformat=]
#define KERN_SOH "\001" /* ASCII Start Of Header */
^
include/linux/printk.h:424:10: note: in definition of macro 'printk_ratelimited'
printk(fmt, ##__VA_ARGS__); \
^~~
include/linux/kern_levels.h:12:22: note: in expansion of macro 'KERN_SOH'
#define KERN_WARNING KERN_SOH "4" /* warning conditions */
^~~~~~~~
include/linux/printk.h:440:21: note: in expansion of macro 'KERN_WARNING'
printk_ratelimited(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
^~~~~~~~~~~~
>> fs/notify/mark.c:587:3: note: in expansion of macro 'pr_warn_ratelimited'
pr_warn_ratelimited("%s: fsid mismatch on object of type %u: %x.%x != %x.%x\n",
^~~~~~~~~~~~~~~~~~~
fs/notify/mark.c:587:77: note: format string is defined here
pr_warn_ratelimited("%s: fsid mismatch on object of type %u: %x.%x != %x.%x\n",
~^
%lx
--
In file included from include/linux/kernel.h:14:0,
from include/linux/list.h:9,
from include/linux/wait.h:7,
from include/linux/wait_bit.h:8,
from include/linux/fs.h:6,
from fs//notify/mark.c:76:
fs//notify/mark.c: In function 'fsnotify_add_mark_list':
>> include/linux/kern_levels.h:5:18: warning: format '%x' expects argument of type 'unsigned int', but argument 4 has type 'long int' [-Wformat=]
#define KERN_SOH "\001" /* ASCII Start Of Header */
^
include/linux/printk.h:424:10: note: in definition of macro 'printk_ratelimited'
printk(fmt, ##__VA_ARGS__); \
^~~
include/linux/kern_levels.h:12:22: note: in expansion of macro 'KERN_SOH'
#define KERN_WARNING KERN_SOH "4" /* warning conditions */
^~~~~~~~
include/linux/printk.h:440:21: note: in expansion of macro 'KERN_WARNING'
printk_ratelimited(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
^~~~~~~~~~~~
fs//notify/mark.c:587:3: note: in expansion of macro 'pr_warn_ratelimited'
pr_warn_ratelimited("%s: fsid mismatch on object of type %u: %x.%x != %x.%x\n",
^~~~~~~~~~~~~~~~~~~
fs//notify/mark.c:587:65: note: format string is defined here
pr_warn_ratelimited("%s: fsid mismatch on object of type %u: %x.%x != %x.%x\n",
~^
%lx
In file included from include/linux/kernel.h:14:0,
from include/linux/list.h:9,
from include/linux/wait.h:7,
from include/linux/wait_bit.h:8,
from include/linux/fs.h:6,
from fs//notify/mark.c:76:
include/linux/kern_levels.h:5:18: warning: format '%x' expects argument of type 'unsigned int', but argument 5 has type 'long int' [-Wformat=]
#define KERN_SOH "\001" /* ASCII Start Of Header */
^
include/linux/printk.h:424:10: note: in definition of macro 'printk_ratelimited'
printk(fmt, ##__VA_ARGS__); \
^~~
include/linux/kern_levels.h:12:22: note: in expansion of macro 'KERN_SOH'
#define KERN_WARNING KERN_SOH "4" /* warning conditions */
^~~~~~~~
include/linux/printk.h:440:21: note: in expansion of macro 'KERN_WARNING'
printk_ratelimited(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
^~~~~~~~~~~~
fs//notify/mark.c:587:3: note: in expansion of macro 'pr_warn_ratelimited'
pr_warn_ratelimited("%s: fsid mismatch on object of type %u: %x.%x != %x.%x\n",
^~~~~~~~~~~~~~~~~~~
fs//notify/mark.c:587:68: note: format string is defined here
pr_warn_ratelimited("%s: fsid mismatch on object of type %u: %x.%x != %x.%x\n",
~^
%lx
In file included from include/linux/kernel.h:14:0,
from include/linux/list.h:9,
from include/linux/wait.h:7,
from include/linux/wait_bit.h:8,
from include/linux/fs.h:6,
from fs//notify/mark.c:76:
include/linux/kern_levels.h:5:18: warning: format '%x' expects argument of type 'unsigned int', but argument 6 has type 'long int' [-Wformat=]
#define KERN_SOH "\001" /* ASCII Start Of Header */
^
include/linux/printk.h:424:10: note: in definition of macro 'printk_ratelimited'
printk(fmt, ##__VA_ARGS__); \
^~~
include/linux/kern_levels.h:12:22: note: in expansion of macro 'KERN_SOH'
#define KERN_WARNING KERN_SOH "4" /* warning conditions */
^~~~~~~~
include/linux/printk.h:440:21: note: in expansion of macro 'KERN_WARNING'
printk_ratelimited(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
^~~~~~~~~~~~
fs//notify/mark.c:587:3: note: in expansion of macro 'pr_warn_ratelimited'
pr_warn_ratelimited("%s: fsid mismatch on object of type %u: %x.%x != %x.%x\n",
^~~~~~~~~~~~~~~~~~~
fs//notify/mark.c:587:74: note: format string is defined here
pr_warn_ratelimited("%s: fsid mismatch on object of type %u: %x.%x != %x.%x\n",
~^
%lx
In file included from include/linux/kernel.h:14:0,
from include/linux/list.h:9,
from include/linux/wait.h:7,
from include/linux/wait_bit.h:8,
from include/linux/fs.h:6,
from fs//notify/mark.c:76:
include/linux/kern_levels.h:5:18: warning: format '%x' expects argument of type 'unsigned int', but argument 7 has type 'long int' [-Wformat=]
#define KERN_SOH "\001" /* ASCII Start Of Header */
^
include/linux/printk.h:424:10: note: in definition of macro 'printk_ratelimited'
printk(fmt, ##__VA_ARGS__); \
^~~
include/linux/kern_levels.h:12:22: note: in expansion of macro 'KERN_SOH'
#define KERN_WARNING KERN_SOH "4" /* warning conditions */
^~~~~~~~
include/linux/printk.h:440:21: note: in expansion of macro 'KERN_WARNING'
printk_ratelimited(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
^~~~~~~~~~~~
fs//notify/mark.c:587:3: note: in expansion of macro 'pr_warn_ratelimited'
pr_warn_ratelimited("%s: fsid mismatch on object of type %u: %x.%x != %x.%x\n",
^~~~~~~~~~~~~~~~~~~
fs//notify/mark.c:587:77: note: format string is defined here
pr_warn_ratelimited("%s: fsid mismatch on object of type %u: %x.%x != %x.%x\n",
~^
%lx
vim +/pr_warn_ratelimited +587 fs/notify/mark.c
545
546 /*
547 * Add mark into proper place in given list of marks. These marks may be used
548 * for the fsnotify backend to determine which event types should be delivered
549 * to which group and for which inodes. These marks are ordered according to
550 * priority, highest number first, and then by the group's location in memory.
551 */
552 static int fsnotify_add_mark_list(struct fsnotify_mark *mark,
553 fsnotify_connp_t *connp, unsigned int type,
554 int allow_dups, __kernel_fsid_t *fsid)
555 {
556 struct fsnotify_mark *lmark, *last = NULL;
557 struct fsnotify_mark_connector *conn;
558 int cmp;
559 int err = 0;
560
561 if (WARN_ON(!fsnotify_valid_obj_type(type)))
562 return -EINVAL;
563
564 /* Backend is expected to check for zero fsid (e.g. tmpfs) */
565 if (fsid && WARN_ON_ONCE(!fsid->val[0] && !fsid->val[1]))
566 return -ENODEV;
567
568 restart:
569 spin_lock(&mark->lock);
570 conn = fsnotify_grab_connector(connp);
571 if (!conn) {
572 spin_unlock(&mark->lock);
573 err = fsnotify_attach_connector_to_object(connp, type, fsid);
574 if (err)
575 return err;
576 goto restart;
577 } else if (fsid && (conn->fsid.val[0] || conn->fsid.val[1]) &&
578 (fsid->val[0] != conn->fsid.val[0] ||
579 fsid->val[1] != conn->fsid.val[1])) {
580 /*
581 * Backend is expected to check for non uniform fsid
582 * (e.g. btrfs), but maybe we missed something?
583 * Only allow setting conn->fsid once to non zero fsid.
584 * inotify and non-fid fanotify groups do not set nor test
585 * conn->fsid.
586 */
> 587 pr_warn_ratelimited("%s: fsid mismatch on object of type %u: %x.%x != %x.%x\n",
588 __func__, conn->type,
589 fsid->val[0], fsid->val[1],
590 conn->fsid.val[0], conn->fsid.val[1]);
591 err = -EXDEV;
592 goto out_err;
593 }
594
595 /* is mark the first mark? */
596 if (hlist_empty(&conn->list)) {
597 hlist_add_head_rcu(&mark->obj_list, &conn->list);
598 goto added;
599 }
600
601 /* should mark be in the middle of the current list? */
602 hlist_for_each_entry(lmark, &conn->list, obj_list) {
603 last = lmark;
604
605 if ((lmark->group == mark->group) &&
606 (lmark->flags & FSNOTIFY_MARK_FLAG_ATTACHED) &&
607 !allow_dups) {
608 err = -EEXIST;
609 goto out_err;
610 }
611
612 cmp = fsnotify_compare_groups(lmark->group, mark->group);
613 if (cmp >= 0) {
614 hlist_add_before_rcu(&mark->obj_list, &lmark->obj_list);
615 goto added;
616 }
617 }
618
619 BUG_ON(last == NULL);
620 /* mark should be the last entry. last is the current last entry */
621 hlist_add_behind_rcu(&mark->obj_list, &last->obj_list);
622 added:
623 mark->connector = conn;
624 out_err:
625 spin_unlock(&conn->lock);
626 spin_unlock(&mark->lock);
627 return err;
628 }
629
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
Hi Amir,
url: https://github.com/0day-ci/linux/commits/Amir-Goldstein/fanotify-add-support-for-more-event-types/20190111-090241
smatch warnings:
fs/notify/fanotify/fanotify.c:194 fanotify_encode_fid() error: uninitialized symbol 'type'.
fs/notify/fanotify/fanotify.c:194 fanotify_encode_fid() error: uninitialized symbol 'err'.
# https://github.com/0day-ci/linux/commit/48b7a1af51abcb893917d986bc5ae5bae2d21ad6
git remote add linux-review https://github.com/0day-ci/linux
git remote update linux-review
git checkout 48b7a1af51abcb893917d986bc5ae5bae2d21ad6
vim +/type +194 fs/notify/fanotify/fanotify.c
1c529063 Eric Paris 2009-12-17 154
688d9244 Amir Goldstein 2019-01-10 155 static int fanotify_encode_fid(struct fanotify_event *event,
48b7a1af Amir Goldstein 2019-01-10 156 const struct path *path, gfp_t gfp,
48b7a1af Amir Goldstein 2019-01-10 157 __kernel_fsid_t *fsid)
688d9244 Amir Goldstein 2019-01-10 158 {
688d9244 Amir Goldstein 2019-01-10 159 struct fanotify_fid *fid = &event->fid;
688d9244 Amir Goldstein 2019-01-10 160 int dwords, bytes = 0;
688d9244 Amir Goldstein 2019-01-10 161 int err, type;
688d9244 Amir Goldstein 2019-01-10 162
48b7a1af Amir Goldstein 2019-01-10 163 if (!fsid)
48b7a1af Amir Goldstein 2019-01-10 164 goto out_err;
48b7a1af Amir Goldstein 2019-01-10 165
688d9244 Amir Goldstein 2019-01-10 166 fid->ext_fh = NULL;
688d9244 Amir Goldstein 2019-01-10 167 dwords = 0;
688d9244 Amir Goldstein 2019-01-10 168 err = -ENOENT;
688d9244 Amir Goldstein 2019-01-10 169 type = exportfs_encode_fh(path->dentry, NULL, &dwords, 0);
688d9244 Amir Goldstein 2019-01-10 170 if (!dwords)
688d9244 Amir Goldstein 2019-01-10 171 goto out_err;
688d9244 Amir Goldstein 2019-01-10 172
688d9244 Amir Goldstein 2019-01-10 173 bytes = dwords << 2;
688d9244 Amir Goldstein 2019-01-10 174 if (bytes > FANOTIFY_INLINE_FH_LEN) {
688d9244 Amir Goldstein 2019-01-10 175 /* Treat failure to allocate fh as failure to allocate event */
688d9244 Amir Goldstein 2019-01-10 176 err = -ENOMEM;
688d9244 Amir Goldstein 2019-01-10 177 fid->ext_fh = kmalloc(bytes, gfp);
688d9244 Amir Goldstein 2019-01-10 178 if (!fid->ext_fh)
688d9244 Amir Goldstein 2019-01-10 179 goto out_err;
688d9244 Amir Goldstein 2019-01-10 180 }
688d9244 Amir Goldstein 2019-01-10 181
688d9244 Amir Goldstein 2019-01-10 182 type = exportfs_encode_fh(path->dentry, fanotify_fid_fh(fid, bytes),
688d9244 Amir Goldstein 2019-01-10 183 &dwords, 0);
688d9244 Amir Goldstein 2019-01-10 184 err = -EINVAL;
688d9244 Amir Goldstein 2019-01-10 185 if (!type || type == FILEID_INVALID || bytes != dwords << 2)
688d9244 Amir Goldstein 2019-01-10 186 goto out_err;
688d9244 Amir Goldstein 2019-01-10 187
48b7a1af Amir Goldstein 2019-01-10 188 fid->fsid = *fsid;
688d9244 Amir Goldstein 2019-01-10 189 event->fh_len = bytes;
688d9244 Amir Goldstein 2019-01-10 190
688d9244 Amir Goldstein 2019-01-10 191 return type;
688d9244 Amir Goldstein 2019-01-10 192
688d9244 Amir Goldstein 2019-01-10 193 out_err:
688d9244 Amir Goldstein 2019-01-10 @194 pr_warn_ratelimited("fanotify: failed to encode fid (fsid=%x.%x, type=%d, bytes=%d, err=%i)\n",
48b7a1af Amir Goldstein 2019-01-10 195 fsid ? fsid->val[0] : 0, fsid ? fsid->val[1] : 0,
688d9244 Amir Goldstein 2019-01-10 196 type, bytes, err);
688d9244 Amir Goldstein 2019-01-10 197 kfree(fid->ext_fh);
688d9244 Amir Goldstein 2019-01-10 198 fid->ext_fh = NULL;
688d9244 Amir Goldstein 2019-01-10 199 event->fh_len = 0;
688d9244 Amir Goldstein 2019-01-10 200
688d9244 Amir Goldstein 2019-01-10 201 return FILEID_INVALID;
688d9244 Amir Goldstein 2019-01-10 202 }
688d9244 Amir Goldstein 2019-01-10 203
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
On Mon, Jan 14, 2019 at 9:31 AM Dan Carpenter <dan.carpenter@oracle.com> wrote: > > Hi Amir, > > url: https://github.com/0day-ci/linux/commits/Amir-Goldstein/fanotify-add-support-for-more-event-types/20190111-090241 > > smatch warnings: > fs/notify/fanotify/fanotify.c:194 fanotify_encode_fid() error: uninitialized symbol 'type'. > fs/notify/fanotify/fanotify.c:194 fanotify_encode_fid() error: uninitialized symbol 'err'. > > # https://github.com/0day-ci/linux/commit/48b7a1af51abcb893917d986bc5ae5bae2d21ad6 > git remote add linux-review https://github.com/0day-ci/linux > git remote update linux-review > git checkout 48b7a1af51abcb893917d986bc5ae5bae2d21ad6 > vim +/type +194 fs/notify/fanotify/fanotify.c > Thanks for the report! > 1c529063 Eric Paris 2009-12-17 154 > 688d9244 Amir Goldstein 2019-01-10 155 static int fanotify_encode_fid(struct fanotify_event *event, > 48b7a1af Amir Goldstein 2019-01-10 156 const struct path *path, gfp_t gfp, > 48b7a1af Amir Goldstein 2019-01-10 157 __kernel_fsid_t *fsid) > 688d9244 Amir Goldstein 2019-01-10 158 { > 688d9244 Amir Goldstein 2019-01-10 159 struct fanotify_fid *fid = &event->fid; > 688d9244 Amir Goldstein 2019-01-10 160 int dwords, bytes = 0; > 688d9244 Amir Goldstein 2019-01-10 161 int err, type; > 688d9244 Amir Goldstein 2019-01-10 162 > 48b7a1af Amir Goldstein 2019-01-10 163 if (!fsid) > 48b7a1af Amir Goldstein 2019-01-10 164 goto out_err; Jan, Can you fix this up on commit to: int err = -ENODEV; int type = FILEID_INVALID; Thanks, Amir.
On Thu 10-01-19 19:04:37, Amir Goldstein wrote: > For FAN_REPORT_FID, we need to encode fid with fsid of the filesystem on > every event. To avoid having to call vfs_statfs() on every event to get > fsid, we store the fsid in fsnotify_mark_connector on the first time we > add a mark and on handle event we use the cached fsid. > > Subsequent calls to add mark on the same object are expected to pass the > same fsid, so the call will fail on cached fsid mismatch. > > If an event is reported on several mark types (inode, mount, filesystem), > all connectors should already have the same fsid, so we use the cached > fsid from the first connector. > > Suggested-by: Jan Kara <jack@suse.cz> > Signed-off-by: Amir Goldstein <amir73il@gmail.com> I've somewhat modified the patch to simplify code flow around fanotify_get_fid() and also made fsid argument for fsnotify_add_mark_locked() mandatory. The resulting patch is attached. Honza > --- > fs/notify/fanotify/fanotify.c | 51 +++++++++++++++++------- > fs/notify/fanotify/fanotify.h | 5 ++- > fs/notify/fanotify/fanotify_user.c | 62 ++++++++++++++++++------------ > fs/notify/mark.c | 47 +++++++++++++++++----- > include/linux/fsnotify_backend.h | 24 +++++++++--- > 5 files changed, 135 insertions(+), 54 deletions(-) > > diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c > index e431f63c9f58..1bbf8b90dd83 100644 > --- a/fs/notify/fanotify/fanotify.c > +++ b/fs/notify/fanotify/fanotify.c > @@ -153,14 +153,16 @@ static u32 fanotify_group_event_mask(struct fsnotify_iter_info *iter_info, > } > > static int fanotify_encode_fid(struct fanotify_event *event, > - const struct path *path, gfp_t gfp) > + const struct path *path, gfp_t gfp, > + __kernel_fsid_t *fsid) > { > struct fanotify_fid *fid = &event->fid; > int dwords, bytes = 0; > - struct kstatfs stat; > int err, type; > > - stat.f_fsid.val[0] = stat.f_fsid.val[1] = 0; > + if (!fsid) > + goto out_err; > + > fid->ext_fh = NULL; > dwords = 0; > err = -ENOENT; > @@ -168,10 +170,6 @@ static int fanotify_encode_fid(struct fanotify_event *event, > if (!dwords) > goto out_err; > > - err = vfs_statfs(path, &stat); > - if (err) > - goto out_err; > - > bytes = dwords << 2; > if (bytes > FANOTIFY_INLINE_FH_LEN) { > /* Treat failure to allocate fh as failure to allocate event */ > @@ -187,14 +185,14 @@ static int fanotify_encode_fid(struct fanotify_event *event, > if (!type || type == FILEID_INVALID || bytes != dwords << 2) > goto out_err; > > - fid->fsid = stat.f_fsid; > + fid->fsid = *fsid; > event->fh_len = bytes; > > return type; > > out_err: > pr_warn_ratelimited("fanotify: failed to encode fid (fsid=%x.%x, type=%d, bytes=%d, err=%i)\n", > - stat.f_fsid.val[0], stat.f_fsid.val[1], > + fsid ? fsid->val[0] : 0, fsid ? fsid->val[1] : 0, > type, bytes, err); > kfree(fid->ext_fh); > fid->ext_fh = NULL; > @@ -204,8 +202,9 @@ static int fanotify_encode_fid(struct fanotify_event *event, > } > > struct fanotify_event *fanotify_alloc_event(struct fsnotify_group *group, > - struct inode *inode, u32 mask, > - const struct path *path) > + struct inode *inode, u32 mask, > + const struct path *path, > + __kernel_fsid_t *fsid) > { > struct fanotify_event *event = NULL; > gfp_t gfp = GFP_KERNEL_ACCOUNT; > @@ -244,7 +243,7 @@ init: __maybe_unused > event->fh_len = 0; > if (path && FAN_GROUP_FLAG(group, FAN_REPORT_FID)) { > /* Report the event without a file identifier on encode error */ > - event->fh_type = fanotify_encode_fid(event, path, gfp); > + event->fh_type = fanotify_encode_fid(event, path, gfp, fsid); > } else if (path) { > event->fh_type = FILEID_ROOT; > event->path = *path; > @@ -259,6 +258,28 @@ init: __maybe_unused > return event; > } > > +/* > + * Get cached fsid of the filesystem containing the object from any connector. > + * All connectors are supposed to have the same fsid, but we do not verify that > + * here. > + */ > +static __kernel_fsid_t *fanotify_get_fsid(struct fsnotify_iter_info *iter_info, > + __kernel_fsid_t *fsid) > +{ > + int type; > + > + fsnotify_foreach_obj_type(type) { > + if (!fsnotify_iter_should_report_type(iter_info, type)) > + continue; > + > + *fsid = iter_info->marks[type]->connector->fsid; > + if (!WARN_ON_ONCE(!fsid->val[0] && !fsid->val[1])) > + return fsid; > + } > + > + return NULL; > +} > + > static int fanotify_handle_event(struct fsnotify_group *group, > struct inode *inode, > u32 mask, const void *data, int data_type, > @@ -268,6 +289,7 @@ static int fanotify_handle_event(struct fsnotify_group *group, > int ret = 0; > struct fanotify_event *event; > struct fsnotify_event *fsn_event; > + __kernel_fsid_t __fsid, *fsid = NULL; > > BUILD_BUG_ON(FAN_ACCESS != FS_ACCESS); > BUILD_BUG_ON(FAN_MODIFY != FS_MODIFY); > @@ -300,7 +322,10 @@ static int fanotify_handle_event(struct fsnotify_group *group, > return 0; > } > > - event = fanotify_alloc_event(group, inode, mask, data); > + if (FAN_GROUP_FLAG(group, FAN_REPORT_FID)) > + fsid = fanotify_get_fsid(iter_info, &__fsid); > + > + event = fanotify_alloc_event(group, inode, mask, data, fsid); > ret = -ENOMEM; > if (unlikely(!event)) { > /* > diff --git a/fs/notify/fanotify/fanotify.h b/fs/notify/fanotify/fanotify.h > index 4aafc7144c3d..5b072afa4e19 100644 > --- a/fs/notify/fanotify/fanotify.h > +++ b/fs/notify/fanotify/fanotify.h > @@ -131,5 +131,6 @@ static inline struct fanotify_event *FANOTIFY_E(struct fsnotify_event *fse) > } > > struct fanotify_event *fanotify_alloc_event(struct fsnotify_group *group, > - struct inode *inode, u32 mask, > - const struct path *path); > + struct inode *inode, u32 mask, > + const struct path *path, > + __kernel_fsid_t *fsid); > diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c > index 211ec6332d31..467e6431fbe9 100644 > --- a/fs/notify/fanotify/fanotify_user.c > +++ b/fs/notify/fanotify/fanotify_user.c > @@ -653,7 +653,8 @@ static __u32 fanotify_mark_add_to_mask(struct fsnotify_mark *fsn_mark, > > static struct fsnotify_mark *fanotify_add_new_mark(struct fsnotify_group *group, > fsnotify_connp_t *connp, > - unsigned int type) > + unsigned int type, > + __kernel_fsid_t *fsid) > { > struct fsnotify_mark *mark; > int ret; > @@ -666,7 +667,7 @@ static struct fsnotify_mark *fanotify_add_new_mark(struct fsnotify_group *group, > return ERR_PTR(-ENOMEM); > > fsnotify_init_mark(mark, group); > - ret = fsnotify_add_mark_locked(mark, connp, type, 0); > + ret = fsnotify_add_mark_locked_fsid(mark, connp, type, 0, fsid); > if (ret) { > fsnotify_put_mark(mark); > return ERR_PTR(ret); > @@ -678,7 +679,8 @@ static struct fsnotify_mark *fanotify_add_new_mark(struct fsnotify_group *group, > > static int fanotify_add_mark(struct fsnotify_group *group, > fsnotify_connp_t *connp, unsigned int type, > - __u32 mask, unsigned int flags) > + __u32 mask, unsigned int flags, > + __kernel_fsid_t *fsid) > { > struct fsnotify_mark *fsn_mark; > __u32 added; > @@ -686,7 +688,7 @@ static int fanotify_add_mark(struct fsnotify_group *group, > mutex_lock(&group->mark_mutex); > fsn_mark = fsnotify_find_mark(connp, group); > if (!fsn_mark) { > - fsn_mark = fanotify_add_new_mark(group, connp, type); > + fsn_mark = fanotify_add_new_mark(group, connp, type, fsid); > if (IS_ERR(fsn_mark)) { > mutex_unlock(&group->mark_mutex); > return PTR_ERR(fsn_mark); > @@ -703,23 +705,23 @@ static int fanotify_add_mark(struct fsnotify_group *group, > > static int fanotify_add_vfsmount_mark(struct fsnotify_group *group, > struct vfsmount *mnt, __u32 mask, > - unsigned int flags) > + unsigned int flags, __kernel_fsid_t *fsid) > { > return fanotify_add_mark(group, &real_mount(mnt)->mnt_fsnotify_marks, > - FSNOTIFY_OBJ_TYPE_VFSMOUNT, mask, flags); > + FSNOTIFY_OBJ_TYPE_VFSMOUNT, mask, flags, fsid); > } > > static int fanotify_add_sb_mark(struct fsnotify_group *group, > - struct super_block *sb, __u32 mask, > - unsigned int flags) > + struct super_block *sb, __u32 mask, > + unsigned int flags, __kernel_fsid_t *fsid) > { > return fanotify_add_mark(group, &sb->s_fsnotify_marks, > - FSNOTIFY_OBJ_TYPE_SB, mask, flags); > + FSNOTIFY_OBJ_TYPE_SB, mask, flags, fsid); > } > > static int fanotify_add_inode_mark(struct fsnotify_group *group, > struct inode *inode, __u32 mask, > - unsigned int flags) > + unsigned int flags, __kernel_fsid_t *fsid) > { > pr_debug("%s: group=%p inode=%p\n", __func__, group, inode); > > @@ -734,7 +736,7 @@ static int fanotify_add_inode_mark(struct fsnotify_group *group, > return 0; > > return fanotify_add_mark(group, &inode->i_fsnotify_marks, > - FSNOTIFY_OBJ_TYPE_INODE, mask, flags); > + FSNOTIFY_OBJ_TYPE_INODE, mask, flags, fsid); > } > > /* fanotify syscalls */ > @@ -798,7 +800,7 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags) > atomic_inc(&user->fanotify_listeners); > group->memcg = get_mem_cgroup_from_mm(current->mm); > > - oevent = fanotify_alloc_event(group, NULL, FS_Q_OVERFLOW, NULL); > + oevent = fanotify_alloc_event(group, NULL, FS_Q_OVERFLOW, NULL, NULL); > if (unlikely(!oevent)) { > fd = -ENOMEM; > goto out_destroy_group; > @@ -861,9 +863,9 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags) > } > > /* Check if filesystem can encode a unique fid */ > -static int fanotify_test_fid(struct path *path) > +static int fanotify_test_fid(struct path *path, struct kstatfs *stat) > { > - struct kstatfs stat, root_stat; > + struct kstatfs root_stat; > struct path root = { > .mnt = path->mnt, > .dentry = path->dentry->d_sb->s_root, > @@ -873,11 +875,11 @@ static int fanotify_test_fid(struct path *path) > /* > * Make sure path is not in filesystem with zero fsid (e.g. tmpfs). > */ > - err = vfs_statfs(path, &stat); > + err = vfs_statfs(path, stat); > if (err) > return err; > > - if (!stat.f_fsid.val[0] && !stat.f_fsid.val[1]) > + if (!stat->f_fsid.val[0] && !stat->f_fsid.val[1]) > return -ENODEV; > > /* > @@ -888,8 +890,8 @@ static int fanotify_test_fid(struct path *path) > if (err) > return err; > > - if (root_stat.f_fsid.val[0] != stat.f_fsid.val[0] || > - root_stat.f_fsid.val[1] != stat.f_fsid.val[1]) > + if (root_stat.f_fsid.val[0] != stat->f_fsid.val[0] || > + root_stat.f_fsid.val[1] != stat->f_fsid.val[1]) > return -EXDEV; > > /* > @@ -914,6 +916,8 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask, > struct fsnotify_group *group; > struct fd f; > struct path path; > + struct kstatfs stat; > + __kernel_fsid_t *fsid = NULL; > u32 valid_mask = FANOTIFY_EVENTS | FANOTIFY_EVENT_FLAGS; > unsigned int mark_type = flags & FANOTIFY_MARK_TYPE_BITS; > int ret; > @@ -992,9 +996,11 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask, > goto fput_and_out; > > if (FAN_GROUP_FLAG(group, FAN_REPORT_FID)) { > - ret = fanotify_test_fid(&path); > + ret = fanotify_test_fid(&path, &stat); > if (ret) > goto path_put_and_out; > + > + fsid = &stat.f_fsid; > } > > /* inode held in place by reference to path; group by fget on fd */ > @@ -1007,19 +1013,25 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask, > switch (flags & (FAN_MARK_ADD | FAN_MARK_REMOVE)) { > case FAN_MARK_ADD: > if (mark_type == FAN_MARK_MOUNT) > - ret = fanotify_add_vfsmount_mark(group, mnt, mask, flags); > + ret = fanotify_add_vfsmount_mark(group, mnt, mask, > + flags, fsid); > else if (mark_type == FAN_MARK_FILESYSTEM) > - ret = fanotify_add_sb_mark(group, mnt->mnt_sb, mask, flags); > + ret = fanotify_add_sb_mark(group, mnt->mnt_sb, mask, > + flags, fsid); > else > - ret = fanotify_add_inode_mark(group, inode, mask, flags); > + ret = fanotify_add_inode_mark(group, inode, mask, > + flags, fsid); > break; > case FAN_MARK_REMOVE: > if (mark_type == FAN_MARK_MOUNT) > - ret = fanotify_remove_vfsmount_mark(group, mnt, mask, flags); > + ret = fanotify_remove_vfsmount_mark(group, mnt, mask, > + flags); > else if (mark_type == FAN_MARK_FILESYSTEM) > - ret = fanotify_remove_sb_mark(group, mnt->mnt_sb, mask, flags); > + ret = fanotify_remove_sb_mark(group, mnt->mnt_sb, mask, > + flags); > else > - ret = fanotify_remove_inode_mark(group, inode, mask, flags); > + ret = fanotify_remove_inode_mark(group, inode, mask, > + flags); > break; > default: > ret = -EINVAL; > diff --git a/fs/notify/mark.c b/fs/notify/mark.c > index d2dd16cb5989..3c5f39cc7fa3 100644 > --- a/fs/notify/mark.c > +++ b/fs/notify/mark.c > @@ -82,6 +82,7 @@ > #include <linux/slab.h> > #include <linux/spinlock.h> > #include <linux/srcu.h> > +#include <linux/ratelimit.h> > > #include <linux/atomic.h> > > @@ -481,7 +482,8 @@ int fsnotify_compare_groups(struct fsnotify_group *a, struct fsnotify_group *b) > } > > static int fsnotify_attach_connector_to_object(fsnotify_connp_t *connp, > - unsigned int type) > + unsigned int type, > + __kernel_fsid_t *fsid) > { > struct inode *inode = NULL; > struct fsnotify_mark_connector *conn; > @@ -493,6 +495,11 @@ static int fsnotify_attach_connector_to_object(fsnotify_connp_t *connp, > INIT_HLIST_HEAD(&conn->list); > conn->type = type; > conn->obj = connp; > + /* Cache fsid of filesystem containing the object */ > + if (fsid) > + conn->fsid = *fsid; > + else > + conn->fsid.val[0] = conn->fsid.val[1] = 0; > if (conn->type == FSNOTIFY_OBJ_TYPE_INODE) > inode = igrab(fsnotify_conn_inode(conn)); > /* > @@ -544,7 +551,7 @@ static struct fsnotify_mark_connector *fsnotify_grab_connector( > */ > static int fsnotify_add_mark_list(struct fsnotify_mark *mark, > fsnotify_connp_t *connp, unsigned int type, > - int allow_dups) > + int allow_dups, __kernel_fsid_t *fsid) > { > struct fsnotify_mark *lmark, *last = NULL; > struct fsnotify_mark_connector *conn; > @@ -553,15 +560,36 @@ static int fsnotify_add_mark_list(struct fsnotify_mark *mark, > > if (WARN_ON(!fsnotify_valid_obj_type(type))) > return -EINVAL; > + > + /* Backend is expected to check for zero fsid (e.g. tmpfs) */ > + if (fsid && WARN_ON_ONCE(!fsid->val[0] && !fsid->val[1])) > + return -ENODEV; > + > restart: > spin_lock(&mark->lock); > conn = fsnotify_grab_connector(connp); > if (!conn) { > spin_unlock(&mark->lock); > - err = fsnotify_attach_connector_to_object(connp, type); > + err = fsnotify_attach_connector_to_object(connp, type, fsid); > if (err) > return err; > goto restart; > + } else if (fsid && (conn->fsid.val[0] || conn->fsid.val[1]) && > + (fsid->val[0] != conn->fsid.val[0] || > + fsid->val[1] != conn->fsid.val[1])) { > + /* > + * Backend is expected to check for non uniform fsid > + * (e.g. btrfs), but maybe we missed something? > + * Only allow setting conn->fsid once to non zero fsid. > + * inotify and non-fid fanotify groups do not set nor test > + * conn->fsid. > + */ > + pr_warn_ratelimited("%s: fsid mismatch on object of type %u: %x.%x != %x.%x\n", > + __func__, conn->type, > + fsid->val[0], fsid->val[1], > + conn->fsid.val[0], conn->fsid.val[1]); > + err = -EXDEV; > + goto out_err; > } > > /* is mark the first mark? */ > @@ -604,9 +632,9 @@ static int fsnotify_add_mark_list(struct fsnotify_mark *mark, > * These marks may be used for the fsnotify backend to determine which > * event types should be delivered to which group. > */ > -int fsnotify_add_mark_locked(struct fsnotify_mark *mark, > - fsnotify_connp_t *connp, unsigned int type, > - int allow_dups) > +int fsnotify_add_mark_locked_fsid(struct fsnotify_mark *mark, > + fsnotify_connp_t *connp, unsigned int type, > + int allow_dups, __kernel_fsid_t *fsid) > { > struct fsnotify_group *group = mark->group; > int ret = 0; > @@ -627,7 +655,7 @@ int fsnotify_add_mark_locked(struct fsnotify_mark *mark, > fsnotify_get_mark(mark); /* for g_list */ > spin_unlock(&mark->lock); > > - ret = fsnotify_add_mark_list(mark, connp, type, allow_dups); > + ret = fsnotify_add_mark_list(mark, connp, type, allow_dups, fsid); > if (ret) > goto err; > > @@ -648,13 +676,14 @@ int fsnotify_add_mark_locked(struct fsnotify_mark *mark, > } > > int fsnotify_add_mark(struct fsnotify_mark *mark, fsnotify_connp_t *connp, > - unsigned int type, int allow_dups) > + unsigned int type, int allow_dups, __kernel_fsid_t *fsid) > { > int ret; > struct fsnotify_group *group = mark->group; > > mutex_lock(&group->mark_mutex); > - ret = fsnotify_add_mark_locked(mark, connp, type, allow_dups); > + ret = fsnotify_add_mark_locked_fsid(mark, connp, type, allow_dups, > + fsid); > mutex_unlock(&group->mark_mutex); > return ret; > } > diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h > index 1e4b88bd1443..b66c4199d629 100644 > --- a/include/linux/fsnotify_backend.h > +++ b/include/linux/fsnotify_backend.h > @@ -293,6 +293,7 @@ typedef struct fsnotify_mark_connector __rcu *fsnotify_connp_t; > struct fsnotify_mark_connector { > spinlock_t lock; > unsigned int type; /* Type of object [lock] */ > + __kernel_fsid_t fsid; /* fsid of filesystem containing object */ > union { > /* Object pointer [lock] */ > fsnotify_connp_t *obj; > @@ -433,20 +434,32 @@ extern void fsnotify_init_mark(struct fsnotify_mark *mark, > /* Find mark belonging to given group in the list of marks */ > extern struct fsnotify_mark *fsnotify_find_mark(fsnotify_connp_t *connp, > struct fsnotify_group *group); > +/* Get cached fsid of filesystem containing object */ > +extern int fsnotify_get_conn_fsid(const struct fsnotify_mark_connector *conn, > + __kernel_fsid_t *fsid); > /* attach the mark to the object */ > extern int fsnotify_add_mark(struct fsnotify_mark *mark, > fsnotify_connp_t *connp, unsigned int type, > - int allow_dups); > -extern int fsnotify_add_mark_locked(struct fsnotify_mark *mark, > - fsnotify_connp_t *connp, unsigned int type, > - int allow_dups); > + int allow_dups, __kernel_fsid_t *fsid); > +extern int fsnotify_add_mark_locked_fsid(struct fsnotify_mark *mark, > + fsnotify_connp_t *connp, > + unsigned int type, int allow_dups, > + __kernel_fsid_t *fsid); > +static inline int fsnotify_add_mark_locked(struct fsnotify_mark *mark, > + fsnotify_connp_t *connp, > + unsigned int type, int allow_dups) > +{ > + return fsnotify_add_mark_locked_fsid(mark, connp, type, allow_dups, > + NULL); > +} > + > /* attach the mark to the inode */ > static inline int fsnotify_add_inode_mark(struct fsnotify_mark *mark, > struct inode *inode, > int allow_dups) > { > return fsnotify_add_mark(mark, &inode->i_fsnotify_marks, > - FSNOTIFY_OBJ_TYPE_INODE, allow_dups); > + FSNOTIFY_OBJ_TYPE_INODE, allow_dups, NULL); > } > static inline int fsnotify_add_inode_mark_locked(struct fsnotify_mark *mark, > struct inode *inode, > @@ -455,6 +468,7 @@ static inline int fsnotify_add_inode_mark_locked(struct fsnotify_mark *mark, > return fsnotify_add_mark_locked(mark, &inode->i_fsnotify_marks, > FSNOTIFY_OBJ_TYPE_INODE, allow_dups); > } > + > /* given a group and a mark, flag mark to be freed when all references are dropped */ > extern void fsnotify_destroy_mark(struct fsnotify_mark *mark, > struct fsnotify_group *group); > -- > 2.17.1 >
On Thu, Feb 7, 2019 at 4:48 PM Jan Kara <jack@suse.cz> wrote: > > On Thu 10-01-19 19:04:37, Amir Goldstein wrote: > > For FAN_REPORT_FID, we need to encode fid with fsid of the filesystem on > > every event. To avoid having to call vfs_statfs() on every event to get > > fsid, we store the fsid in fsnotify_mark_connector on the first time we > > add a mark and on handle event we use the cached fsid. > > > > Subsequent calls to add mark on the same object are expected to pass the > > same fsid, so the call will fail on cached fsid mismatch. > > > > If an event is reported on several mark types (inode, mount, filesystem), > > all connectors should already have the same fsid, so we use the cached > > fsid from the first connector. > > > > Suggested-by: Jan Kara <jack@suse.cz> > > Signed-off-by: Amir Goldstein <amir73il@gmail.com> > > I've somewhat modified the patch to simplify code flow around > fanotify_get_fid() and also made fsid argument for > fsnotify_add_mark_locked() mandatory. The resulting patch is attached. > ACK. Two nits. 1. Dan Carpenter reported a smatch warning. Please fix: fs/notify/fanotify/fanotify.c:194 fanotify_encode_fid() error: uninitialized symbol 'type'. fs/notify/fanotify/fanotify.c:194 fanotify_encode_fid() error: uninitialized symbol 'err'. 2. checkpatch doesn't like cutting long debug strings into 80 chars (and Greg's linuxsty.vim plugin doesn't warn about them) referring to the long string that you broke up pr_warn_ratelimited("%s: fsid mismatch on object of type %u: "... Thanks, Amir.
On Thu 07-02-19 18:31:19, Amir Goldstein wrote: > On Thu, Feb 7, 2019 at 4:48 PM Jan Kara <jack@suse.cz> wrote: > > > > On Thu 10-01-19 19:04:37, Amir Goldstein wrote: > > > For FAN_REPORT_FID, we need to encode fid with fsid of the filesystem on > > > every event. To avoid having to call vfs_statfs() on every event to get > > > fsid, we store the fsid in fsnotify_mark_connector on the first time we > > > add a mark and on handle event we use the cached fsid. > > > > > > Subsequent calls to add mark on the same object are expected to pass the > > > same fsid, so the call will fail on cached fsid mismatch. > > > > > > If an event is reported on several mark types (inode, mount, filesystem), > > > all connectors should already have the same fsid, so we use the cached > > > fsid from the first connector. > > > > > > Suggested-by: Jan Kara <jack@suse.cz> > > > Signed-off-by: Amir Goldstein <amir73il@gmail.com> > > > > I've somewhat modified the patch to simplify code flow around > > fanotify_get_fid() and also made fsid argument for > > fsnotify_add_mark_locked() mandatory. The resulting patch is attached. > > > > ACK. Two nits. > > 1. Dan Carpenter reported a smatch warning. Please fix: > > fs/notify/fanotify/fanotify.c:194 fanotify_encode_fid() error: > uninitialized symbol 'type'. > fs/notify/fanotify/fanotify.c:194 fanotify_encode_fid() error: > uninitialized symbol 'err'. Yes, but this problem went away with my changes as well since we do 'goto out_err' only after setting err and type. > 2. checkpatch doesn't like cutting long debug strings into 80 chars > (and Greg's linuxsty.vim plugin doesn't warn about them) > referring to the long string that you broke up > pr_warn_ratelimited("%s: fsid mismatch on object of type %u: "... I know and I don't take that too seriously. The point is: You don't want to break the string so that it is easily greppable. But as long as the core part of the string is in one line, it's OK. In particular once you get to the part of the format string where you have the format specifiers, breaking the string is irrelevant for grepping anymore since nobody can sanely grep that part of the string. And I took care to follow these guidances. Honza
diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c index e431f63c9f58..1bbf8b90dd83 100644 --- a/fs/notify/fanotify/fanotify.c +++ b/fs/notify/fanotify/fanotify.c @@ -153,14 +153,16 @@ static u32 fanotify_group_event_mask(struct fsnotify_iter_info *iter_info, } static int fanotify_encode_fid(struct fanotify_event *event, - const struct path *path, gfp_t gfp) + const struct path *path, gfp_t gfp, + __kernel_fsid_t *fsid) { struct fanotify_fid *fid = &event->fid; int dwords, bytes = 0; - struct kstatfs stat; int err, type; - stat.f_fsid.val[0] = stat.f_fsid.val[1] = 0; + if (!fsid) + goto out_err; + fid->ext_fh = NULL; dwords = 0; err = -ENOENT; @@ -168,10 +170,6 @@ static int fanotify_encode_fid(struct fanotify_event *event, if (!dwords) goto out_err; - err = vfs_statfs(path, &stat); - if (err) - goto out_err; - bytes = dwords << 2; if (bytes > FANOTIFY_INLINE_FH_LEN) { /* Treat failure to allocate fh as failure to allocate event */ @@ -187,14 +185,14 @@ static int fanotify_encode_fid(struct fanotify_event *event, if (!type || type == FILEID_INVALID || bytes != dwords << 2) goto out_err; - fid->fsid = stat.f_fsid; + fid->fsid = *fsid; event->fh_len = bytes; return type; out_err: pr_warn_ratelimited("fanotify: failed to encode fid (fsid=%x.%x, type=%d, bytes=%d, err=%i)\n", - stat.f_fsid.val[0], stat.f_fsid.val[1], + fsid ? fsid->val[0] : 0, fsid ? fsid->val[1] : 0, type, bytes, err); kfree(fid->ext_fh); fid->ext_fh = NULL; @@ -204,8 +202,9 @@ static int fanotify_encode_fid(struct fanotify_event *event, } struct fanotify_event *fanotify_alloc_event(struct fsnotify_group *group, - struct inode *inode, u32 mask, - const struct path *path) + struct inode *inode, u32 mask, + const struct path *path, + __kernel_fsid_t *fsid) { struct fanotify_event *event = NULL; gfp_t gfp = GFP_KERNEL_ACCOUNT; @@ -244,7 +243,7 @@ init: __maybe_unused event->fh_len = 0; if (path && FAN_GROUP_FLAG(group, FAN_REPORT_FID)) { /* Report the event without a file identifier on encode error */ - event->fh_type = fanotify_encode_fid(event, path, gfp); + event->fh_type = fanotify_encode_fid(event, path, gfp, fsid); } else if (path) { event->fh_type = FILEID_ROOT; event->path = *path; @@ -259,6 +258,28 @@ init: __maybe_unused return event; } +/* + * Get cached fsid of the filesystem containing the object from any connector. + * All connectors are supposed to have the same fsid, but we do not verify that + * here. + */ +static __kernel_fsid_t *fanotify_get_fsid(struct fsnotify_iter_info *iter_info, + __kernel_fsid_t *fsid) +{ + int type; + + fsnotify_foreach_obj_type(type) { + if (!fsnotify_iter_should_report_type(iter_info, type)) + continue; + + *fsid = iter_info->marks[type]->connector->fsid; + if (!WARN_ON_ONCE(!fsid->val[0] && !fsid->val[1])) + return fsid; + } + + return NULL; +} + static int fanotify_handle_event(struct fsnotify_group *group, struct inode *inode, u32 mask, const void *data, int data_type, @@ -268,6 +289,7 @@ static int fanotify_handle_event(struct fsnotify_group *group, int ret = 0; struct fanotify_event *event; struct fsnotify_event *fsn_event; + __kernel_fsid_t __fsid, *fsid = NULL; BUILD_BUG_ON(FAN_ACCESS != FS_ACCESS); BUILD_BUG_ON(FAN_MODIFY != FS_MODIFY); @@ -300,7 +322,10 @@ static int fanotify_handle_event(struct fsnotify_group *group, return 0; } - event = fanotify_alloc_event(group, inode, mask, data); + if (FAN_GROUP_FLAG(group, FAN_REPORT_FID)) + fsid = fanotify_get_fsid(iter_info, &__fsid); + + event = fanotify_alloc_event(group, inode, mask, data, fsid); ret = -ENOMEM; if (unlikely(!event)) { /* diff --git a/fs/notify/fanotify/fanotify.h b/fs/notify/fanotify/fanotify.h index 4aafc7144c3d..5b072afa4e19 100644 --- a/fs/notify/fanotify/fanotify.h +++ b/fs/notify/fanotify/fanotify.h @@ -131,5 +131,6 @@ static inline struct fanotify_event *FANOTIFY_E(struct fsnotify_event *fse) } struct fanotify_event *fanotify_alloc_event(struct fsnotify_group *group, - struct inode *inode, u32 mask, - const struct path *path); + struct inode *inode, u32 mask, + const struct path *path, + __kernel_fsid_t *fsid); diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c index 211ec6332d31..467e6431fbe9 100644 --- a/fs/notify/fanotify/fanotify_user.c +++ b/fs/notify/fanotify/fanotify_user.c @@ -653,7 +653,8 @@ static __u32 fanotify_mark_add_to_mask(struct fsnotify_mark *fsn_mark, static struct fsnotify_mark *fanotify_add_new_mark(struct fsnotify_group *group, fsnotify_connp_t *connp, - unsigned int type) + unsigned int type, + __kernel_fsid_t *fsid) { struct fsnotify_mark *mark; int ret; @@ -666,7 +667,7 @@ static struct fsnotify_mark *fanotify_add_new_mark(struct fsnotify_group *group, return ERR_PTR(-ENOMEM); fsnotify_init_mark(mark, group); - ret = fsnotify_add_mark_locked(mark, connp, type, 0); + ret = fsnotify_add_mark_locked_fsid(mark, connp, type, 0, fsid); if (ret) { fsnotify_put_mark(mark); return ERR_PTR(ret); @@ -678,7 +679,8 @@ static struct fsnotify_mark *fanotify_add_new_mark(struct fsnotify_group *group, static int fanotify_add_mark(struct fsnotify_group *group, fsnotify_connp_t *connp, unsigned int type, - __u32 mask, unsigned int flags) + __u32 mask, unsigned int flags, + __kernel_fsid_t *fsid) { struct fsnotify_mark *fsn_mark; __u32 added; @@ -686,7 +688,7 @@ static int fanotify_add_mark(struct fsnotify_group *group, mutex_lock(&group->mark_mutex); fsn_mark = fsnotify_find_mark(connp, group); if (!fsn_mark) { - fsn_mark = fanotify_add_new_mark(group, connp, type); + fsn_mark = fanotify_add_new_mark(group, connp, type, fsid); if (IS_ERR(fsn_mark)) { mutex_unlock(&group->mark_mutex); return PTR_ERR(fsn_mark); @@ -703,23 +705,23 @@ static int fanotify_add_mark(struct fsnotify_group *group, static int fanotify_add_vfsmount_mark(struct fsnotify_group *group, struct vfsmount *mnt, __u32 mask, - unsigned int flags) + unsigned int flags, __kernel_fsid_t *fsid) { return fanotify_add_mark(group, &real_mount(mnt)->mnt_fsnotify_marks, - FSNOTIFY_OBJ_TYPE_VFSMOUNT, mask, flags); + FSNOTIFY_OBJ_TYPE_VFSMOUNT, mask, flags, fsid); } static int fanotify_add_sb_mark(struct fsnotify_group *group, - struct super_block *sb, __u32 mask, - unsigned int flags) + struct super_block *sb, __u32 mask, + unsigned int flags, __kernel_fsid_t *fsid) { return fanotify_add_mark(group, &sb->s_fsnotify_marks, - FSNOTIFY_OBJ_TYPE_SB, mask, flags); + FSNOTIFY_OBJ_TYPE_SB, mask, flags, fsid); } static int fanotify_add_inode_mark(struct fsnotify_group *group, struct inode *inode, __u32 mask, - unsigned int flags) + unsigned int flags, __kernel_fsid_t *fsid) { pr_debug("%s: group=%p inode=%p\n", __func__, group, inode); @@ -734,7 +736,7 @@ static int fanotify_add_inode_mark(struct fsnotify_group *group, return 0; return fanotify_add_mark(group, &inode->i_fsnotify_marks, - FSNOTIFY_OBJ_TYPE_INODE, mask, flags); + FSNOTIFY_OBJ_TYPE_INODE, mask, flags, fsid); } /* fanotify syscalls */ @@ -798,7 +800,7 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags) atomic_inc(&user->fanotify_listeners); group->memcg = get_mem_cgroup_from_mm(current->mm); - oevent = fanotify_alloc_event(group, NULL, FS_Q_OVERFLOW, NULL); + oevent = fanotify_alloc_event(group, NULL, FS_Q_OVERFLOW, NULL, NULL); if (unlikely(!oevent)) { fd = -ENOMEM; goto out_destroy_group; @@ -861,9 +863,9 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags) } /* Check if filesystem can encode a unique fid */ -static int fanotify_test_fid(struct path *path) +static int fanotify_test_fid(struct path *path, struct kstatfs *stat) { - struct kstatfs stat, root_stat; + struct kstatfs root_stat; struct path root = { .mnt = path->mnt, .dentry = path->dentry->d_sb->s_root, @@ -873,11 +875,11 @@ static int fanotify_test_fid(struct path *path) /* * Make sure path is not in filesystem with zero fsid (e.g. tmpfs). */ - err = vfs_statfs(path, &stat); + err = vfs_statfs(path, stat); if (err) return err; - if (!stat.f_fsid.val[0] && !stat.f_fsid.val[1]) + if (!stat->f_fsid.val[0] && !stat->f_fsid.val[1]) return -ENODEV; /* @@ -888,8 +890,8 @@ static int fanotify_test_fid(struct path *path) if (err) return err; - if (root_stat.f_fsid.val[0] != stat.f_fsid.val[0] || - root_stat.f_fsid.val[1] != stat.f_fsid.val[1]) + if (root_stat.f_fsid.val[0] != stat->f_fsid.val[0] || + root_stat.f_fsid.val[1] != stat->f_fsid.val[1]) return -EXDEV; /* @@ -914,6 +916,8 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask, struct fsnotify_group *group; struct fd f; struct path path; + struct kstatfs stat; + __kernel_fsid_t *fsid = NULL; u32 valid_mask = FANOTIFY_EVENTS | FANOTIFY_EVENT_FLAGS; unsigned int mark_type = flags & FANOTIFY_MARK_TYPE_BITS; int ret; @@ -992,9 +996,11 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask, goto fput_and_out; if (FAN_GROUP_FLAG(group, FAN_REPORT_FID)) { - ret = fanotify_test_fid(&path); + ret = fanotify_test_fid(&path, &stat); if (ret) goto path_put_and_out; + + fsid = &stat.f_fsid; } /* inode held in place by reference to path; group by fget on fd */ @@ -1007,19 +1013,25 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask, switch (flags & (FAN_MARK_ADD | FAN_MARK_REMOVE)) { case FAN_MARK_ADD: if (mark_type == FAN_MARK_MOUNT) - ret = fanotify_add_vfsmount_mark(group, mnt, mask, flags); + ret = fanotify_add_vfsmount_mark(group, mnt, mask, + flags, fsid); else if (mark_type == FAN_MARK_FILESYSTEM) - ret = fanotify_add_sb_mark(group, mnt->mnt_sb, mask, flags); + ret = fanotify_add_sb_mark(group, mnt->mnt_sb, mask, + flags, fsid); else - ret = fanotify_add_inode_mark(group, inode, mask, flags); + ret = fanotify_add_inode_mark(group, inode, mask, + flags, fsid); break; case FAN_MARK_REMOVE: if (mark_type == FAN_MARK_MOUNT) - ret = fanotify_remove_vfsmount_mark(group, mnt, mask, flags); + ret = fanotify_remove_vfsmount_mark(group, mnt, mask, + flags); else if (mark_type == FAN_MARK_FILESYSTEM) - ret = fanotify_remove_sb_mark(group, mnt->mnt_sb, mask, flags); + ret = fanotify_remove_sb_mark(group, mnt->mnt_sb, mask, + flags); else - ret = fanotify_remove_inode_mark(group, inode, mask, flags); + ret = fanotify_remove_inode_mark(group, inode, mask, + flags); break; default: ret = -EINVAL; diff --git a/fs/notify/mark.c b/fs/notify/mark.c index d2dd16cb5989..3c5f39cc7fa3 100644 --- a/fs/notify/mark.c +++ b/fs/notify/mark.c @@ -82,6 +82,7 @@ #include <linux/slab.h> #include <linux/spinlock.h> #include <linux/srcu.h> +#include <linux/ratelimit.h> #include <linux/atomic.h> @@ -481,7 +482,8 @@ int fsnotify_compare_groups(struct fsnotify_group *a, struct fsnotify_group *b) } static int fsnotify_attach_connector_to_object(fsnotify_connp_t *connp, - unsigned int type) + unsigned int type, + __kernel_fsid_t *fsid) { struct inode *inode = NULL; struct fsnotify_mark_connector *conn; @@ -493,6 +495,11 @@ static int fsnotify_attach_connector_to_object(fsnotify_connp_t *connp, INIT_HLIST_HEAD(&conn->list); conn->type = type; conn->obj = connp; + /* Cache fsid of filesystem containing the object */ + if (fsid) + conn->fsid = *fsid; + else + conn->fsid.val[0] = conn->fsid.val[1] = 0; if (conn->type == FSNOTIFY_OBJ_TYPE_INODE) inode = igrab(fsnotify_conn_inode(conn)); /* @@ -544,7 +551,7 @@ static struct fsnotify_mark_connector *fsnotify_grab_connector( */ static int fsnotify_add_mark_list(struct fsnotify_mark *mark, fsnotify_connp_t *connp, unsigned int type, - int allow_dups) + int allow_dups, __kernel_fsid_t *fsid) { struct fsnotify_mark *lmark, *last = NULL; struct fsnotify_mark_connector *conn; @@ -553,15 +560,36 @@ static int fsnotify_add_mark_list(struct fsnotify_mark *mark, if (WARN_ON(!fsnotify_valid_obj_type(type))) return -EINVAL; + + /* Backend is expected to check for zero fsid (e.g. tmpfs) */ + if (fsid && WARN_ON_ONCE(!fsid->val[0] && !fsid->val[1])) + return -ENODEV; + restart: spin_lock(&mark->lock); conn = fsnotify_grab_connector(connp); if (!conn) { spin_unlock(&mark->lock); - err = fsnotify_attach_connector_to_object(connp, type); + err = fsnotify_attach_connector_to_object(connp, type, fsid); if (err) return err; goto restart; + } else if (fsid && (conn->fsid.val[0] || conn->fsid.val[1]) && + (fsid->val[0] != conn->fsid.val[0] || + fsid->val[1] != conn->fsid.val[1])) { + /* + * Backend is expected to check for non uniform fsid + * (e.g. btrfs), but maybe we missed something? + * Only allow setting conn->fsid once to non zero fsid. + * inotify and non-fid fanotify groups do not set nor test + * conn->fsid. + */ + pr_warn_ratelimited("%s: fsid mismatch on object of type %u: %x.%x != %x.%x\n", + __func__, conn->type, + fsid->val[0], fsid->val[1], + conn->fsid.val[0], conn->fsid.val[1]); + err = -EXDEV; + goto out_err; } /* is mark the first mark? */ @@ -604,9 +632,9 @@ static int fsnotify_add_mark_list(struct fsnotify_mark *mark, * These marks may be used for the fsnotify backend to determine which * event types should be delivered to which group. */ -int fsnotify_add_mark_locked(struct fsnotify_mark *mark, - fsnotify_connp_t *connp, unsigned int type, - int allow_dups) +int fsnotify_add_mark_locked_fsid(struct fsnotify_mark *mark, + fsnotify_connp_t *connp, unsigned int type, + int allow_dups, __kernel_fsid_t *fsid) { struct fsnotify_group *group = mark->group; int ret = 0; @@ -627,7 +655,7 @@ int fsnotify_add_mark_locked(struct fsnotify_mark *mark, fsnotify_get_mark(mark); /* for g_list */ spin_unlock(&mark->lock); - ret = fsnotify_add_mark_list(mark, connp, type, allow_dups); + ret = fsnotify_add_mark_list(mark, connp, type, allow_dups, fsid); if (ret) goto err; @@ -648,13 +676,14 @@ int fsnotify_add_mark_locked(struct fsnotify_mark *mark, } int fsnotify_add_mark(struct fsnotify_mark *mark, fsnotify_connp_t *connp, - unsigned int type, int allow_dups) + unsigned int type, int allow_dups, __kernel_fsid_t *fsid) { int ret; struct fsnotify_group *group = mark->group; mutex_lock(&group->mark_mutex); - ret = fsnotify_add_mark_locked(mark, connp, type, allow_dups); + ret = fsnotify_add_mark_locked_fsid(mark, connp, type, allow_dups, + fsid); mutex_unlock(&group->mark_mutex); return ret; } diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h index 1e4b88bd1443..b66c4199d629 100644 --- a/include/linux/fsnotify_backend.h +++ b/include/linux/fsnotify_backend.h @@ -293,6 +293,7 @@ typedef struct fsnotify_mark_connector __rcu *fsnotify_connp_t; struct fsnotify_mark_connector { spinlock_t lock; unsigned int type; /* Type of object [lock] */ + __kernel_fsid_t fsid; /* fsid of filesystem containing object */ union { /* Object pointer [lock] */ fsnotify_connp_t *obj; @@ -433,20 +434,32 @@ extern void fsnotify_init_mark(struct fsnotify_mark *mark, /* Find mark belonging to given group in the list of marks */ extern struct fsnotify_mark *fsnotify_find_mark(fsnotify_connp_t *connp, struct fsnotify_group *group); +/* Get cached fsid of filesystem containing object */ +extern int fsnotify_get_conn_fsid(const struct fsnotify_mark_connector *conn, + __kernel_fsid_t *fsid); /* attach the mark to the object */ extern int fsnotify_add_mark(struct fsnotify_mark *mark, fsnotify_connp_t *connp, unsigned int type, - int allow_dups); -extern int fsnotify_add_mark_locked(struct fsnotify_mark *mark, - fsnotify_connp_t *connp, unsigned int type, - int allow_dups); + int allow_dups, __kernel_fsid_t *fsid); +extern int fsnotify_add_mark_locked_fsid(struct fsnotify_mark *mark, + fsnotify_connp_t *connp, + unsigned int type, int allow_dups, + __kernel_fsid_t *fsid); +static inline int fsnotify_add_mark_locked(struct fsnotify_mark *mark, + fsnotify_connp_t *connp, + unsigned int type, int allow_dups) +{ + return fsnotify_add_mark_locked_fsid(mark, connp, type, allow_dups, + NULL); +} + /* attach the mark to the inode */ static inline int fsnotify_add_inode_mark(struct fsnotify_mark *mark, struct inode *inode, int allow_dups) { return fsnotify_add_mark(mark, &inode->i_fsnotify_marks, - FSNOTIFY_OBJ_TYPE_INODE, allow_dups); + FSNOTIFY_OBJ_TYPE_INODE, allow_dups, NULL); } static inline int fsnotify_add_inode_mark_locked(struct fsnotify_mark *mark, struct inode *inode, @@ -455,6 +468,7 @@ static inline int fsnotify_add_inode_mark_locked(struct fsnotify_mark *mark, return fsnotify_add_mark_locked(mark, &inode->i_fsnotify_marks, FSNOTIFY_OBJ_TYPE_INODE, allow_dups); } + /* given a group and a mark, flag mark to be freed when all references are dropped */ extern void fsnotify_destroy_mark(struct fsnotify_mark *mark, struct fsnotify_group *group);
For FAN_REPORT_FID, we need to encode fid with fsid of the filesystem on every event. To avoid having to call vfs_statfs() on every event to get fsid, we store the fsid in fsnotify_mark_connector on the first time we add a mark and on handle event we use the cached fsid. Subsequent calls to add mark on the same object are expected to pass the same fsid, so the call will fail on cached fsid mismatch. If an event is reported on several mark types (inode, mount, filesystem), all connectors should already have the same fsid, so we use the cached fsid from the first connector. Suggested-by: Jan Kara <jack@suse.cz> Signed-off-by: Amir Goldstein <amir73il@gmail.com> --- fs/notify/fanotify/fanotify.c | 51 +++++++++++++++++------- fs/notify/fanotify/fanotify.h | 5 ++- fs/notify/fanotify/fanotify_user.c | 62 ++++++++++++++++++------------ fs/notify/mark.c | 47 +++++++++++++++++----- include/linux/fsnotify_backend.h | 24 +++++++++--- 5 files changed, 135 insertions(+), 54 deletions(-)