This is a note to let you know that I've just added the patch titled
of: module: prevent NULL pointer dereference in vsnprintf()
to the 6.6-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:
of-module-prevent-null-pointer-dereference-in-vsnprintf.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From a1aa5390cc912934fee76ce80af5f940452fa987 Mon Sep 17 00:00:00 2001
From: Sergey Shtylyov <s.shtylyov@xxxxxx>
Date: Wed, 27 Mar 2024 19:52:49 +0300
Subject: of: module: prevent NULL pointer dereference in vsnprintf()
From: Sergey Shtylyov <s.shtylyov@xxxxxx>
commit a1aa5390cc912934fee76ce80af5f940452fa987 upstream.
In of_modalias(), we can get passed the str and len parameters which would
cause a kernel oops in vsnprintf() since it only allows passing a NULL ptr
when the length is also 0. Also, we need to filter out the negative values
of the len parameter as these will result in a really huge buffer since
snprintf() takes size_t parameter while ours is ssize_t...
Found by Linux Verification Center (linuxtesting.org) with the Svace static
analysis tool.
Signed-off-by: Sergey Shtylyov <s.shtylyov@xxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Link: https://lore.kernel.org/r/1d211023-3923-685b-20f0-f3f90ea56e1f@xxxxxx
Signed-off-by: Rob Herring <robh@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/of/module.c | 8 ++++++++
1 file changed, 8 insertions(+)
--- a/drivers/of/module.c
+++ b/drivers/of/module.c
@@ -16,6 +16,14 @@ ssize_t of_modalias(const struct device_
ssize_t csize;
ssize_t tsize;
+ /*
+ * Prevent a kernel oops in vsnprintf() -- it only allows passing a
+ * NULL ptr when the length is also 0. Also filter out the negative
+ * lengths...
+ */
+ if ((len > 0 && !str) || len < 0)
+ return -EINVAL;
+
/* Name & Type */
/* %p eats all alphanum characters, so %c must be used here */
csize = snprintf(str, len, "of:N%pOFn%c%s", np, 'T',
Patches currently in stable-queue which might be from s.shtylyov@xxxxxx are
queue-6.6/of-module-prevent-null-pointer-dereference-in-vsnprintf.patch
queue-6.6/net-ravb-always-update-error-counters.patch
queue-6.6/net-ravb-let-ip-specific-receive-function-to-interro.patch
queue-6.6/net-ravb-always-process-tx-descriptor-ring.patch
