This is a note to let you know that I've just added the patch titled
xen/privcmd: Fix a possible warning in privcmd_ioctl_mmap_resource()
to the 5.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
xen-privcmd-fix-a-possible-warning-in-privcmd_ioctl_.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 24ee8ae19b52e8ecd784d11965da8ef3a62d28ea
Author: Harshit Mogalapalli <harshit.m.mogalapalli@xxxxxxxxxx>
Date: Fri Nov 25 21:07:45 2022 -0800
xen/privcmd: Fix a possible warning in privcmd_ioctl_mmap_resource()
[ Upstream commit 8b997b2bb2c53b76a6db6c195930e9ab8e4b0c79 ]
As 'kdata.num' is user-controlled data, if user tries to allocate
memory larger than(>=) MAX_ORDER, then kcalloc() will fail, it
creates a stack trace and messes up dmesg with a warning.
Call trace:
-> privcmd_ioctl
--> privcmd_ioctl_mmap_resource
Add __GFP_NOWARN in order to avoid too large allocation warning.
This is detected by static analysis using smatch.
Fixes: 3ad0876554ca ("xen/privcmd: add IOCTL_PRIVCMD_MMAP_RESOURCE")
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@xxxxxxxxxx>
Reviewed-by: Juergen Gross <jgross@xxxxxxxx>
Link: https://lore.kernel.org/r/20221126050745.778967-1-harshit.m.mogalapalli@xxxxxxxxxx
Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/xen/privcmd.c b/drivers/xen/privcmd.c
index cd5f2f09468e..28537a1a0e0b 100644
--- a/drivers/xen/privcmd.c
+++ b/drivers/xen/privcmd.c
@@ -760,7 +760,7 @@ static long privcmd_ioctl_mmap_resource(struct file *file,
goto out;
}
- pfns = kcalloc(kdata.num, sizeof(*pfns), GFP_KERNEL);
+ pfns = kcalloc(kdata.num, sizeof(*pfns), GFP_KERNEL | __GFP_NOWARN);
if (!pfns) {
rc = -ENOMEM;
goto out;
