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| author | Mohammed Gamal <mgamal@redhat.com> | 2023-02-17 23:44:11 +0300 |
|---|---|---|
| committer | Wei Liu <wei.liu@kernel.org> | 2023-03-06 18:28:03 +0300 |
| commit | 1eb65c8687316c65140b48fad27133d583178e15 (patch) | |
| tree | 1bf6ff42afba23bac4d108742e586765d895a17e /drivers/hv | |
| parent | fe15c26ee26efa11741a7b632e9f23b01aca4cc6 (diff) | |
| download | linux-1eb65c8687316c65140b48fad27133d583178e15.tar.xz | |
Drivers: vmbus: Check for channel allocation before looking up relids
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>
Diffstat (limited to 'drivers/hv')
| -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]); |