Patch "octeontx2-af: Add validation before accessing cgx and lmac" has been added to the 6.4-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    octeontx2-af: Add validation before accessing cgx and lmac

to the 6.4-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:
     octeontx2-af-add-validation-before-accessing-cgx-and.patch
and it can be found in the queue-6.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 6f30c568f863455f5246959022a050716b94da38
Author: Hariprasad Kelam <hkelam@xxxxxxxxxxx>
Date:   Fri Jun 30 11:58:44 2023 +0530

    octeontx2-af: Add validation before accessing cgx and lmac
    
    [ Upstream commit 79ebb53772c95d3a6ae51b3c65f9985fdd430df6 ]
    
    with the addition of new MAC blocks like CN10K RPM and CN10KB
    RPM_USX, LMACs are noncontiguous and CGX blocks are also
    noncontiguous. But during RVU driver initialization, the driver
    is assuming they are contiguous and trying to access
    cgx or lmac with their id which is resulting in kernel panic.
    
    This patch fixes the issue by adding proper checks.
    
    [   23.219150] pc : cgx_lmac_read+0x38/0x70
    [   23.219154] lr : rvu_program_channels+0x3f0/0x498
    [   23.223852] sp : ffff000100d6fc80
    [   23.227158] x29: ffff000100d6fc80 x28: ffff00010009f880 x27:
    000000000000005a
    [   23.234288] x26: ffff000102586768 x25: 0000000000002500 x24:
    fffffffffff0f000
    
    Fixes: 91c6945ea1f9 ("octeontx2-af: cn10k: Add RPM MAC support")
    Signed-off-by: Hariprasad Kelam <hkelam@xxxxxxxxxxx>
    Signed-off-by: Sunil Goutham <sgoutham@xxxxxxxxxxx>
    Reviewed-by: Simon Horman <simon.horman@xxxxxxxxxxxx>
    Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/net/ethernet/marvell/octeontx2/af/cgx.c b/drivers/net/ethernet/marvell/octeontx2/af/cgx.c
index bd77152bb8d7c..f4bdca662d616 100644
--- a/drivers/net/ethernet/marvell/octeontx2/af/cgx.c
+++ b/drivers/net/ethernet/marvell/octeontx2/af/cgx.c
@@ -169,6 +169,9 @@ void cgx_lmac_write(int cgx_id, int lmac_id, u64 offset, u64 val)
 {
 	struct cgx *cgx_dev = cgx_get_pdata(cgx_id);
 
+	/* Software must not access disabled LMAC registers */
+	if (!is_lmac_valid(cgx_dev, lmac_id))
+		return;
 	cgx_write(cgx_dev, lmac_id, offset, val);
 }
 
@@ -176,6 +179,10 @@ u64 cgx_lmac_read(int cgx_id, int lmac_id, u64 offset)
 {
 	struct cgx *cgx_dev = cgx_get_pdata(cgx_id);
 
+	/* Software must not access disabled LMAC registers */
+	if (!is_lmac_valid(cgx_dev, lmac_id))
+		return 0;
+
 	return cgx_read(cgx_dev, lmac_id, offset);
 }