[PATCH -next v2] acpi/hmat: fix memory leaks in hmat_init()

[PATCH -next v2] acpi/hmat: fix memory leaks in hmat_init()

[Qian Cai]

The commit 665ac7e92757 ("acpi/hmat: Register processor domain to its
memory") introduced some memory leaks below due to it fails to release
the heap memory in an error path, and then those statically-allocated
__initdata memory which reference them get freed during boot renders
those heap memory as leaks. Since it is valid to pass NULL to
acpi_put_table(), it is fine to call it even if acpi_get_table() returns
an error.

unreferenced object 0xc8ff8008349e9400 (size 128):
  comm "swapper/0", pid 1, jiffies 4294709236 (age 48121.476s)
  hex dump (first 32 bytes):
    00 d0 9e 34 08 80 ff 84 d8 00 43 11 00 10 ff ff  ...4......C.....
    00 00 00 00 ff ff ff ff 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<00000000869d4503>] __kmalloc+0x568/0x600
    [<0000000070fd6afb>] alloc_memory_target+0x50/0xd8
    [<00000000efa2081e>] srat_parse_mem_affinity+0x58/0x5c
    [<000000008bfaef74>] acpi_parse_entries_array+0x1c8/0x2c0
    [<0000000022804877>] acpi_table_parse_entries_array+0x11c/0x138
    [<00000000ffe9cd34>] acpi_table_parse_entries+0x7c/0xac
    [<00000000a7023afd>] hmat_init+0x90/0x174
    [<00000000694a86c1>] do_one_initcall+0x2d8/0x5f8
    [<0000000024889da9>] do_initcall_level+0x37c/0x3fc
    [<000000009be02908>] do_basic_setup+0x38/0x50
    [<0000000037b3ac0a>] kernel_init_freeable+0x194/0x258
    [<00000000f5741184>] kernel_init+0x18/0x334
    [<000000007b30f423>] ret_from_fork+0x10/0x18
    [<000000006c7147a8>] 0xffffffffffffffff

Signed-off-by: Qian Cai <cai@lca.pw>
---

v2: goto out_put per Rafael.

 drivers/acpi/hmat/hmat.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/acpi/hmat/hmat.c b/drivers/acpi/hmat/hmat.c
index b7824a0309f7..69cdb3cea545 100644
--- a/drivers/acpi/hmat/hmat.c
+++ b/drivers/acpi/hmat/hmat.c
@@ -637,7 +637,7 @@ static __init int hmat_init(void)
 
 	status = acpi_get_table(ACPI_SIG_HMAT, 0, &tbl);
 	if (ACPI_FAILURE(status))
-		return 0;
+		goto out_put;
 
 	hmat_revision = tbl->revision;
 	switch (hmat_revision) {
-- 
2.17.2 (Apple Git-113)

Re: [PATCH -next v2] acpi/hmat: fix memory leaks in hmat_init()

[Rafael J. Wysocki]

On Wed, Apr 10, 2019 at 4:15 AM Qian Cai <cai@lca.pw> wrote:
>
> The commit 665ac7e92757 ("acpi/hmat: Register processor domain to its
> memory") introduced some memory leaks below due to it fails to release
> the heap memory in an error path, and then those statically-allocated
> __initdata memory which reference them get freed during boot renders
> those heap memory as leaks. Since it is valid to pass NULL to
> acpi_put_table(), it is fine to call it even if acpi_get_table() returns
> an error.
>
> unreferenced object 0xc8ff8008349e9400 (size 128):
>   comm "swapper/0", pid 1, jiffies 4294709236 (age 48121.476s)
>   hex dump (first 32 bytes):
>     00 d0 9e 34 08 80 ff 84 d8 00 43 11 00 10 ff ff  ...4......C.....
>     00 00 00 00 ff ff ff ff 00 00 00 00 00 00 00 00  ................
>   backtrace:
>     [<00000000869d4503>] __kmalloc+0x568/0x600
>     [<0000000070fd6afb>] alloc_memory_target+0x50/0xd8
>     [<00000000efa2081e>] srat_parse_mem_affinity+0x58/0x5c
>     [<000000008bfaef74>] acpi_parse_entries_array+0x1c8/0x2c0
>     [<0000000022804877>] acpi_table_parse_entries_array+0x11c/0x138
>     [<00000000ffe9cd34>] acpi_table_parse_entries+0x7c/0xac
>     [<00000000a7023afd>] hmat_init+0x90/0x174
>     [<00000000694a86c1>] do_one_initcall+0x2d8/0x5f8
>     [<0000000024889da9>] do_initcall_level+0x37c/0x3fc
>     [<000000009be02908>] do_basic_setup+0x38/0x50
>     [<0000000037b3ac0a>] kernel_init_freeable+0x194/0x258
>     [<00000000f5741184>] kernel_init+0x18/0x334
>     [<000000007b30f423>] ret_from_fork+0x10/0x18
>     [<000000006c7147a8>] 0xffffffffffffffff
>

Fixes: 665ac7e92757 ("acpi/hmat: Register processor domain to its memory")

> Signed-off-by: Qian Cai <cai@lca.pw>

Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Greg, the patch fixed by this is in your tree, so can you apply this
one too, please?

> ---
>
> v2: goto out_put per Rafael.
>
>  drivers/acpi/hmat/hmat.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/acpi/hmat/hmat.c b/drivers/acpi/hmat/hmat.c
> index b7824a0309f7..69cdb3cea545 100644
> --- a/drivers/acpi/hmat/hmat.c
> +++ b/drivers/acpi/hmat/hmat.c
> @@ -637,7 +637,7 @@ static __init int hmat_init(void)
>
>         status = acpi_get_table(ACPI_SIG_HMAT, 0, &tbl);
>         if (ACPI_FAILURE(status))
> -               return 0;
> +               goto out_put;
>
>         hmat_revision = tbl->revision;
>         switch (hmat_revision) {
> --
> 2.17.2 (Apple Git-113)
>