diff mbox series

net: ethernet: ti: cpsw_ale: Fix access to un-initialized memory

Message ID c709f0325a7244ff133e405d017d9efba3b200f6.1636406827.git.christophe.jaillet@wanadoo.fr (mailing list archive)
State Accepted
Commit 7a166854b4e24c57d56b3eba9fe1594985ee0a2c
Delegated to: Netdev Maintainers
Headers show
Series net: ethernet: ti: cpsw_ale: Fix access to un-initialized memory | expand

Checks

Context Check Description
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix warning Target tree name not specified in the subject
netdev/cover_letter success Single patches do not need cover letters
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 0 this patch: 0
netdev/cc_maintainers success CCed 8 of 8 maintainers
netdev/build_clang success Errors and warnings before: 6 this patch: 6
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/verify_fixes success Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 0 this patch: 0
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 12 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
netdev/tree_selection success Guessing tree name failed - patch did not apply

Commit Message

Christophe JAILLET Nov. 8, 2021, 9:28 p.m. UTC
It is spurious to allocate a bitmap without initializing it.
So, better safe than sorry, initialize it to 0 at least to have some known
values.

While at it, switch to the devm_bitmap_ API which is less verbose.

Fixes: 4b41d3436796 ("net: ethernet: ti: cpsw: allow untagged traffic on host port")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
---
Maybe this patch is useless, because of some _add_vlan _del_vlan stuff that
initialize things correctly before they are used, but it really looks
spurious to me.
IIUC, cpsw_rx_vlan_encap() (and the embedded cpsw_ale_get_vlan_p0_untag()
could test any bit in the un-initialized bitmap)

Just a guess, I've not tried to understand all the logic involved.
---
 drivers/net/ethernet/ti/cpsw_ale.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

Comments

patchwork-bot+netdevbpf@kernel.org Nov. 10, 2021, 2:40 p.m. UTC | #1
Hello:

This patch was applied to netdev/net.git (master)
by David S. Miller <davem@davemloft.net>:

On Mon,  8 Nov 2021 22:28:55 +0100 you wrote:
> It is spurious to allocate a bitmap without initializing it.
> So, better safe than sorry, initialize it to 0 at least to have some known
> values.
> 
> While at it, switch to the devm_bitmap_ API which is less verbose.
> 
> Fixes: 4b41d3436796 ("net: ethernet: ti: cpsw: allow untagged traffic on host port")
> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
> 
> [...]

Here is the summary with links:
  - net: ethernet: ti: cpsw_ale: Fix access to un-initialized memory
    https://git.kernel.org/netdev/net/c/7a166854b4e2

You are awesome, thank you!
diff mbox series

Patch

diff --git a/drivers/net/ethernet/ti/cpsw_ale.c b/drivers/net/ethernet/ti/cpsw_ale.c
index 0c75e0576ee1..1ef0aaef5c61 100644
--- a/drivers/net/ethernet/ti/cpsw_ale.c
+++ b/drivers/net/ethernet/ti/cpsw_ale.c
@@ -1299,10 +1299,8 @@  struct cpsw_ale *cpsw_ale_create(struct cpsw_ale_params *params)
 	if (!ale)
 		return ERR_PTR(-ENOMEM);
 
-	ale->p0_untag_vid_mask =
-		devm_kmalloc_array(params->dev, BITS_TO_LONGS(VLAN_N_VID),
-				   sizeof(unsigned long),
-				   GFP_KERNEL);
+	ale->p0_untag_vid_mask = devm_bitmap_zalloc(params->dev, VLAN_N_VID,
+						    GFP_KERNEL);
 	if (!ale->p0_untag_vid_mask)
 		return ERR_PTR(-ENOMEM);