5.15-stable review patch. If anyone has any objections, please let me know.
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From: Billy Tsai billy_tsai@aspeedtech.com
[ Upstream commit b53e9758a31c683fc8615df930262192ed5f034b ]
The `i3c_master_bus_init` function may attach the I2C devices before the I3C bus initialization. In this flow, the DAT `alloc_entry`` will be used before the DAT `init`. Additionally, if the `i3c_master_bus_init` fails, the DAT `cleanup` will execute before the device is detached, which will execue DAT `free_entry` function. The above scenario can cause the driver to use DAT_data when it is NULL.
Signed-off-by: Billy Tsai billy_tsai@aspeedtech.com Link: https://lore.kernel.org/r/20231023080237.560936-1-billy_tsai@aspeedtech.com Signed-off-by: Alexandre Belloni alexandre.belloni@bootlin.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/i3c/master/mipi-i3c-hci/dat_v1.c | 29 ++++++++++++++++-------- 1 file changed, 19 insertions(+), 10 deletions(-)
diff --git a/drivers/i3c/master/mipi-i3c-hci/dat_v1.c b/drivers/i3c/master/mipi-i3c-hci/dat_v1.c index 97bb49ff5b53b..47b9b4d4ed3fc 100644 --- a/drivers/i3c/master/mipi-i3c-hci/dat_v1.c +++ b/drivers/i3c/master/mipi-i3c-hci/dat_v1.c @@ -64,15 +64,17 @@ static int hci_dat_v1_init(struct i3c_hci *hci) return -EOPNOTSUPP; }
- /* use a bitmap for faster free slot search */ - hci->DAT_data = bitmap_zalloc(hci->DAT_entries, GFP_KERNEL); - if (!hci->DAT_data) - return -ENOMEM; - - /* clear them */ - for (dat_idx = 0; dat_idx < hci->DAT_entries; dat_idx++) { - dat_w0_write(dat_idx, 0); - dat_w1_write(dat_idx, 0); + if (!hci->DAT_data) { + /* use a bitmap for faster free slot search */ + hci->DAT_data = bitmap_zalloc(hci->DAT_entries, GFP_KERNEL); + if (!hci->DAT_data) + return -ENOMEM; + + /* clear them */ + for (dat_idx = 0; dat_idx < hci->DAT_entries; dat_idx++) { + dat_w0_write(dat_idx, 0); + dat_w1_write(dat_idx, 0); + } }
return 0; @@ -87,7 +89,13 @@ static void hci_dat_v1_cleanup(struct i3c_hci *hci) static int hci_dat_v1_alloc_entry(struct i3c_hci *hci) { unsigned int dat_idx; + int ret;
+ if (!hci->DAT_data) { + ret = hci_dat_v1_init(hci); + if (ret) + return ret; + } dat_idx = find_first_zero_bit(hci->DAT_data, hci->DAT_entries); if (dat_idx >= hci->DAT_entries) return -ENOENT; @@ -103,7 +111,8 @@ static void hci_dat_v1_free_entry(struct i3c_hci *hci, unsigned int dat_idx) { dat_w0_write(dat_idx, 0); dat_w1_write(dat_idx, 0); - __clear_bit(dat_idx, hci->DAT_data); + if (hci->DAT_data) + __clear_bit(dat_idx, hci->DAT_data); }
static void hci_dat_v1_set_dynamic_addr(struct i3c_hci *hci,