2022-01-08 15:10:12

by Tom Rix

Subject: [PATCH] i3c: master: dw: check return of dw_i3c_master_get_free_pos()

From: Tom Rix <[email protected]>

Clang static analysis reports this problem
dw-i3c-master.c:799:9: warning: The result of the left shift is
undefined because the left operand is negative
COMMAND_PORT_DEV_INDEX(pos) |
^~~~~~~~~~~~~~~~~~~~~~~~~~~

pos can be negative because dw_i3c_master_get_free_pos() can return an
error. So check for an error.

Fixes: 1dd728f5d4d4 ("i3c: master: Add driver for Synopsys DesignWare IP")
Signed-off-by: Tom Rix <[email protected]>
---
drivers/i3c/master/dw-i3c-master.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/i3c/master/dw-i3c-master.c b/drivers/i3c/master/dw-i3c-master.c
index 03a368da51b95..51a8608203de7 100644
--- a/drivers/i3c/master/dw-i3c-master.c
+++ b/drivers/i3c/master/dw-i3c-master.c
@@ -793,6 +793,10 @@ static int dw_i3c_master_daa(struct i3c_master_controller *m)
return -ENOMEM;

pos = dw_i3c_master_get_free_pos(master);
+ if (pos < 0) {
+ dw_i3c_master_free_xfer(xfer);
+ return pos;
+ }
cmd = &xfer->cmds[0];
cmd->cmd_hi = 0x1;
cmd->cmd_lo = COMMAND_PORT_DEV_COUNT(master->maxdevs - pos) |
--
2.26.3

2022-01-13 01:07:17

by Alexandre Belloni

Subject: Re: [PATCH] i3c: master: dw: check return of dw_i3c_master_get_free_pos()

On Sat, 8 Jan 2022 07:09:48 -0800, [email protected] wrote:
> From: Tom Rix <[email protected]>
>
> Clang static analysis reports this problem
> dw-i3c-master.c:799:9: warning: The result of the left shift is
> undefined because the left operand is negative
> COMMAND_PORT_DEV_INDEX(pos) |
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~
>
> [...]

Applied, thanks!

[1/1] i3c: master: dw: check return of dw_i3c_master_get_free_pos()
commit: 13462ba1815db5a96891293a9cfaa2451f7bd623

Best regards,
--
Alexandre Belloni <[email protected]>