diff options
| author | Alessandro Carminati <alessandro.carminati@gmail.com> | 2023-09-21 07:32:17 +0000 |
|---|---|---|
| committer | Stephen Boyd <sboyd@kernel.org> | 2023-10-12 17:30:54 -0700 |
| commit | ceb87a361d0b079ecbc7d2831618c19087f304a9 (patch) | |
| tree | 83a85d5c66fe6545dc6ed8909ab8acec0d29de8e /drivers/clk/clk.c | |
| parent | 601cb6d573facde5fc88efa935b074da64ae63c9 (diff) | |
clk: Sanitize possible_parent_show to Handle Return Value of of_clk_get_parent_name
In the possible_parent_show function, ensure proper handling of the return
value from of_clk_get_parent_name to prevent potential issues arising from
a NULL return.
The current implementation invokes seq_puts directly on the result of
of_clk_get_parent_name without verifying the return value, which can lead
to kernel panic if the function returns NULL.
This patch addresses the concern by introducing a check on the return
value of of_clk_get_parent_name. If the return value is not NULL, the
function proceeds to call seq_puts, providing the returned value as
argument.
However, if of_clk_get_parent_name returns NULL, the function provides a
static string as argument, avoiding the panic.
Fixes: 1ccc0ddf046a ("clk: Use seq_puts() in possible_parent_show()")
Reported-by: Philip Daly <pdaly@redhat.com>
Signed-off-by: Alessandro Carminati (Red Hat) <alessandro.carminati@gmail.com>
Link: https://lore.kernel.org/r/20230921073217.572151-1-alessandro.carminati@gmail.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Diffstat (limited to 'drivers/clk/clk.c')
| -rw-r--r-- | drivers/clk/clk.c | 21 |
1 files changed, 12 insertions, 9 deletions
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index c249f9791ae8..473563bc7496 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -3416,6 +3416,7 @@ static void possible_parent_show(struct seq_file *s, struct clk_core *core, unsigned int i, char terminator) { struct clk_core *parent; + const char *name = NULL; /* * Go through the following options to fetch a parent's name. @@ -3430,18 +3431,20 @@ static void possible_parent_show(struct seq_file *s, struct clk_core *core, * registered (yet). */ parent = clk_core_get_parent_by_index(core, i); - if (parent) + if (parent) { seq_puts(s, parent->name); - else if (core->parents[i].name) + } else if (core->parents[i].name) { seq_puts(s, core->parents[i].name); - else if (core->parents[i].fw_name) + } else if (core->parents[i].fw_name) { seq_printf(s, "<%s>(fw)", core->parents[i].fw_name); - else if (core->parents[i].index >= 0) - seq_puts(s, - of_clk_get_parent_name(core->of_node, - core->parents[i].index)); - else - seq_puts(s, "(missing)"); + } else { + if (core->parents[i].index >= 0) + name = of_clk_get_parent_name(core->of_node, core->parents[i].index); + if (!name) + name = "(missing)"; + + seq_puts(s, name); + } seq_putc(s, terminator); } |