[Devel] [PATCH vz10 v2 1/2] dm-ploop: use the ERRNO fault injection class for ploop_get_delta_file()

[Devel] [PATCH vz10 v2 1/2] dm-ploop: use the ERRNO fault injection class for ploop_get_delta_file()

[Konstantin Khorenko]

ploop_get_delta_file() returns a valid struct file * or an ERR_PTR(),
never NULL, and its only caller relies on exactly that.

The function, however, is annotated as

	ALLOW_ERROR_INJECTION(ploop_get_delta_file, ERRNO_NULL);

So injecting a failure the default way makes the function return NULL,
the NULL sails past IS_ERR() and vfs_fsync() dereferences it.

This is the annotation misdescribing the function rather than a missing
check in the caller: NULL is not a value ploop_get_delta_file() can ever
return. Use the ERRNO class, which injects error pointers only.

Fixes: 4fc49f0700e2 ("dm-ploop: Allow fault injection for all ploop functions")
Feature: dm-ploop: ploop target driver
https://virtuozzo.atlassian.net/browse/VSTOR-137234
Signed-off-by: Konstantin Khorenko <khorenko@virtuozzo.com>
Reviewed-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>
---
 drivers/md/dm-ploop-target.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/md/dm-ploop-target.c b/drivers/md/dm-ploop-target.c
index 0de0e84d440d0..7dab95402def7 100644
--- a/drivers/md/dm-ploop-target.c
+++ b/drivers/md/dm-ploop-target.c
@@ -255,7 +255,7 @@ static struct file *ploop_get_delta_file(struct ploop *ploop, int fd)
 	return ERR_PTR(ret);
 
 }
-ALLOW_ERROR_INJECTION(ploop_get_delta_file, ERRNO_NULL);
+ALLOW_ERROR_INJECTION(ploop_get_delta_file, ERRNO);
 
 static int ploop_check_top_delta(struct ploop *ploop, struct file *file)
 {
-- 
2.43.0

[Devel] [PATCH vz10 v2 2/2] dm-ploop: fix NULL deref in ploop_destroy() when ploop_ctr() failed early

[Konstantin Khorenko]

ploop_ctr() can fail early on setting up the ploop->kt_allocator,
so ploop_destroy() must check it for NULL before dereferencing.

Fixes: 9429d1119a69 ("dm-ploop: make filespace preallocations async")
Feature: dm-ploop: ploop target driver
https://virtuozzo.atlassian.net/browse/VSTOR-137234
Signed-off-by: Konstantin Khorenko <khorenko@virtuozzo.com>
Reviewed-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>
---
 drivers/md/dm-ploop-target.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/md/dm-ploop-target.c b/drivers/md/dm-ploop-target.c
index 7dab95402def7..3b589579741c6 100644
--- a/drivers/md/dm-ploop-target.c
+++ b/drivers/md/dm-ploop-target.c
@@ -188,7 +188,9 @@ static void ploop_destroy(struct ploop *ploop)
 
 		/* waits for the thread to stop */
 		kthread_stop(ploop->kt_worker->task);
-		kthread_stop(ploop->kt_allocator->task);
+		/* kt_allocator may be NULL if ploop_ctr() failed early */
+		if (ploop->kt_allocator)
+			kthread_stop(ploop->kt_allocator->task);
 
 		WARN_ON(!llist_empty(&ploop->pios[PLOOP_LIST_PREPARE]));
 		WARN_ON(!llist_empty(&ploop->llresubmit_pios));
-- 
2.43.0

[Devel] [PATCH RHEL10 COMMIT] dm-ploop: fix NULL deref in ploop_destroy() when ploop_ctr() failed early

[Konstantin Khorenko]

The commit is pushed to "branch-rh10-6.12.0-211.39.1.16.x.vz10-ovz" and will appear at git at bitbucket.org:openvz/vzkernel.git
after rh10-6.12.0-211.39.1.16.6.vz10
------>
commit 34e8c5f7f782ec22e77bd1752695cafb0cb98282
Author: Konstantin Khorenko <khorenko@virtuozzo.com>
Date:   Wed Aug 19 18:33:20 2026 +0200

    dm-ploop: fix NULL deref in ploop_destroy() when ploop_ctr() failed early
    
    ploop_ctr() can fail early on setting up the ploop->kt_allocator,
    so ploop_destroy() must check it for NULL before dereferencing.
    
    Fixes: 9429d1119a69 ("dm-ploop: make filespace preallocations async")
    Feature: dm-ploop: ploop target driver
    https://virtuozzo.atlassian.net/browse/VSTOR-137234
    Signed-off-by: Konstantin Khorenko <khorenko@virtuozzo.com>
    Reviewed-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>
---
 drivers/md/dm-ploop-target.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/md/dm-ploop-target.c b/drivers/md/dm-ploop-target.c
index 7dab95402def7..3b589579741c6 100644
--- a/drivers/md/dm-ploop-target.c
+++ b/drivers/md/dm-ploop-target.c
@@ -188,7 +188,9 @@ static void ploop_destroy(struct ploop *ploop)
 
 		/* waits for the thread to stop */
 		kthread_stop(ploop->kt_worker->task);
-		kthread_stop(ploop->kt_allocator->task);
+		/* kt_allocator may be NULL if ploop_ctr() failed early */
+		if (ploop->kt_allocator)
+			kthread_stop(ploop->kt_allocator->task);
 
 		WARN_ON(!llist_empty(&ploop->pios[PLOOP_LIST_PREPARE]));
 		WARN_ON(!llist_empty(&ploop->llresubmit_pios));

[Devel] [PATCH RHEL10 COMMIT] dm-ploop: use the ERRNO fault injection class for ploop_get_delta_file()

[Konstantin Khorenko]

The commit is pushed to "branch-rh10-6.12.0-211.39.1.16.x.vz10-ovz" and will appear at git at bitbucket.org:openvz/vzkernel.git
after rh10-6.12.0-211.39.1.16.6.vz10
------>
commit 1ab5dd2ffa73d34985c1e57dd4e3ab27c04fb4d4
Author: Konstantin Khorenko <khorenko@virtuozzo.com>
Date:   Wed Aug 19 18:33:35 2026 +0200

    dm-ploop: use the ERRNO fault injection class for ploop_get_delta_file()
    
    ploop_get_delta_file() returns a valid struct file * or an ERR_PTR(),
    never NULL, and its only caller relies on exactly that.
    
    The function, however, is annotated as
    
            ALLOW_ERROR_INJECTION(ploop_get_delta_file, ERRNO_NULL);
    
    So injecting a failure the default way makes the function return NULL,
    the NULL sails past IS_ERR() and vfs_fsync() dereferences it.
    
    This is the annotation misdescribing the function rather than a missing
    check in the caller: NULL is not a value ploop_get_delta_file() can ever
    return. Use the ERRNO class, which injects error pointers only.
    
    Fixes: 4fc49f0700e2 ("dm-ploop: Allow fault injection for all ploop functions")
    Feature: dm-ploop: ploop target driver
    https://virtuozzo.atlassian.net/browse/VSTOR-137234
    Signed-off-by: Konstantin Khorenko <khorenko@virtuozzo.com>
    Reviewed-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>
---
 drivers/md/dm-ploop-target.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/md/dm-ploop-target.c b/drivers/md/dm-ploop-target.c
index 0de0e84d440d0..7dab95402def7 100644
--- a/drivers/md/dm-ploop-target.c
+++ b/drivers/md/dm-ploop-target.c
@@ -255,7 +255,7 @@ static struct file *ploop_get_delta_file(struct ploop *ploop, int fd)
 	return ERR_PTR(ret);
 
 }
-ALLOW_ERROR_INJECTION(ploop_get_delta_file, ERRNO_NULL);
+ALLOW_ERROR_INJECTION(ploop_get_delta_file, ERRNO);
 
 static int ploop_check_top_delta(struct ploop *ploop, struct file *file)
 {