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i3c: master: Fix dynamic address leak when 'assigned-address' is present

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If the DTS contains 'assigned-address', a dynamic address leak occurs
during hotjoin events.

Assume a device have assigned-address 0xb.
  - Device issue Hotjoin
  - Call i3c_master_do_daa()
  - Call driver xxx_do_daa()
  - Call i3c_master_get_free_addr() to get dynamic address 0x9
  - i3c_master_add_i3c_dev_locked(0x9)
  -     expected_dyn_addr  = newdev->boardinfo->init_dyn_addr (0xb);
  -     i3c_master_reattach_i3c_dev(newdev(0xb), old_dyn_addr(0x9));
  -         if (dev->info.dyn_addr != old_dyn_addr &&
                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 0xb != 0x9 -> TRUE
                (!dev->boardinfo ||
                 ^^^^^^^^^^^^^^^ ->  FALSE
                 dev->info.dyn_addr != dev->boardinfo->init_dyn_addr)) {
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
                 0xb != 0xb      ->  FALSE
                 ...
                 i3c_bus_set_addr_slot_status(&master->bus, old_dyn_addr,
                                                     I3C_ADDR_SLOT_FREE);
		 ^^^
                 This will be skipped. So old_dyn_addr never free
            }

  - i3c_master_get_free_addr() will return increased sequence number.

Remove dev->info.dyn_addr != dev->boardinfo->init_dyn_addr condition check.
dev->info.dyn_addr should be checked before calling this function because
i3c_master_setnewda_locked() has already been called and the target device
has already accepted dyn_addr. It is too late to check if dyn_addr is free
in i3c_master_reattach_i3c_dev().

Add check to ensure expected_dyn_addr is free before
i3c_master_setnewda_locked().

Fixes: cc3a392d69b6 ("i3c: master: fix for SETDASA and DAA process")
Cc: stable@kernel.org
Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
Link: https://lore.kernel.org/r/20241021-i3c_dts_assign-v8-3-4098b8bde01e@nxp.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
This commit is contained in:
Frank Li 2024-10-21 11:45:08 -04:00 committed by Alexandre Belloni
parent 2f552fa280
commit 851bd21cdb
1 changed files with 5 additions and 10 deletions
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15
drivers/i3c/master.c
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@ -1548,16 +1548,9 @@ static int i3c_master_reattach_i3c_dev(struct i3c_dev_desc *dev,
u8 old_dyn_addr)
{
struct i3c_master_controller *master = i3c_dev_get_master(dev);
enum i3c_addr_slot_status status;
int ret;
if (dev->info.dyn_addr != old_dyn_addr &&
(!dev->boardinfo ||
dev->info.dyn_addr != dev->boardinfo->init_dyn_addr)) {
status = i3c_bus_get_addr_slot_status(&master->bus,
dev->info.dyn_addr);
if (status != I3C_ADDR_SLOT_FREE)
return -EBUSY;
if (dev->info.dyn_addr != old_dyn_addr) {
i3c_bus_set_addr_slot_status(&master->bus,
dev->info.dyn_addr,
I3C_ADDR_SLOT_I3C_DEV);
@ -1960,9 +1953,10 @@ static int i3c_master_bus_init(struct i3c_master_controller *master)
goto err_rstdaa;
}
/* Do not mark as occupied until real device exist in bus */
i3c_bus_set_addr_slot_status_mask(&master->bus,
i3cboardinfo->init_dyn_addr,
I3C_ADDR_SLOT_I3C_DEV | I3C_ADDR_SLOT_EXT_DESIRED,
I3C_ADDR_SLOT_EXT_DESIRED,
I3C_ADDR_SLOT_EXT_STATUS_MASK);
/*
@ -2126,7 +2120,8 @@ int i3c_master_add_i3c_dev_locked(struct i3c_master_controller *master,
else
expected_dyn_addr = newdev->info.dyn_addr;
if (newdev->info.dyn_addr != expected_dyn_addr) {
if (newdev->info.dyn_addr != expected_dyn_addr &&
i3c_bus_get_addr_slot_status(&master->bus, expected_dyn_addr) == I3C_ADDR_SLOT_FREE) {
/*
* Try to apply the expected dynamic address. If it fails, keep
* the address assigned by the master.