diff options
| author | Mohammed Gamal | 2023-02-17 22:44:11 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman | 2023-04-13 16:55:18 +0200 |
| commit | 8c3f0ae5435fd20bb1e3a8308488aa6ac33151ee (patch) | |
| tree | bfc8ab7208f57d04b4bf29a14db3753ca620c32d | |
| parent | 8df93c8da5327b4eb1cfebf7efa5271c89b3a377 (diff) | |
Drivers: vmbus: Check for channel allocation before looking up relids
[ Upstream commit 1eb65c8687316c65140b48fad27133d583178e15 ]
relid2channel() assumes vmbus channel array to be allocated when called.
However, in cases such as kdump/kexec, not all relids will be reset by the host.
When the second kernel boots and if the guest receives a vmbus interrupt during
vmbus driver initialization before vmbus_connect() is called, before it finishes,
or if it fails, the vmbus interrupt service routine is called which in turn calls
relid2channel() and can cause a null pointer dereference.
Print a warning and error out in relid2channel() for a channel id that's invalid
in the second kernel.
Fixes: 8b6a877c060e ("Drivers: hv: vmbus: Replace the per-CPU channel lists with a global array of channels")
Signed-off-by: Mohammed Gamal <mgamal@redhat.com>
Reviewed-by: Dexuan Cui <decui@microsoft.com>
Link: https://lore.kernel.org/r/20230217204411.212709-1-mgamal@redhat.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | drivers/hv/connection.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c index 9dc27e5d367a..da51b50787df 100644 --- a/drivers/hv/connection.c +++ b/drivers/hv/connection.c @@ -409,6 +409,10 @@ void vmbus_disconnect(void) */ struct vmbus_channel *relid2channel(u32 relid) { + if (vmbus_connection.channels == NULL) { + pr_warn_once("relid2channel: relid=%d: No channels mapped!\n", relid); + return NULL; + } if (WARN_ON(relid >= MAX_CHANNEL_RELIDS)) return NULL; return READ_ONCE(vmbus_connection.channels[relid]); |