| Message ID | 20201105125154.GA176426@mwanda (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 4e59dd249cd513a211e2ecce2cb31f4e29a5ce5b |
| Headers | show |
| Series | ASoC: qcom: common: Fix refcounting in qcom_snd_parse_of() | expand |
On Thu, 5 Nov 2020 15:51:54 +0300, Dan Carpenter wrote: > There are two issues in this function. > > 1) We can't drop the refrences on "cpu", "codec" and "platform" before > we take the reference. This doesn't cause a problem on the first > iteration because those pointers start as NULL so the of_node_put() > is a no-op. But on the subsequent iterations, it will lead to a use > after free. > > [...] Applied to https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git for-next Thanks! [1/1] ASoC: qcom: common: Fix refcounting in qcom_snd_parse_of() commit: 4e59dd249cd513a211e2ecce2cb31f4e29a5ce5b All being well this means that it will be integrated into the linux-next tree (usually sometime in the next 24 hours) and sent to Linus during the next merge window (or sooner if it is a bug fix), however if problems are discovered then the patch may be dropped or reverted. You may get further e-mails resulting from automated or manual testing and review of the tree, please engage with people reporting problems and send followup patches addressing any issues that are reported if needed. If any updates are required or you are submitting further changes they should be sent as incremental updates against current git, existing patches will not be replaced. Please add any relevant lists and maintainers to the CCs when replying to this mail. Thanks, Mark
diff --git a/sound/soc/qcom/common.c b/sound/soc/qcom/common.c index 54660f126d09..09af00700700 100644 --- a/sound/soc/qcom/common.c +++ b/sound/soc/qcom/common.c @@ -58,7 +58,7 @@ int qcom_snd_parse_of(struct snd_soc_card *card) dlc = devm_kzalloc(dev, 2 * sizeof(*dlc), GFP_KERNEL); if (!dlc) { ret = -ENOMEM; - goto err; + goto err_put_np; } link->cpus = &dlc[0]; @@ -70,7 +70,7 @@ int qcom_snd_parse_of(struct snd_soc_card *card) ret = of_property_read_string(np, "link-name", &link->name); if (ret) { dev_err(card->dev, "error getting codec dai_link name\n"); - goto err; + goto err_put_np; } cpu = of_get_child_by_name(np, "cpu"); @@ -130,8 +130,10 @@ int qcom_snd_parse_of(struct snd_soc_card *card) } else { /* DPCM frontend */ dlc = devm_kzalloc(dev, sizeof(*dlc), GFP_KERNEL); - if (!dlc) - return -ENOMEM; + if (!dlc) { + ret = -ENOMEM; + goto err; + } link->codecs = dlc; link->num_codecs = 1; @@ -158,10 +160,11 @@ int qcom_snd_parse_of(struct snd_soc_card *card) return 0; err: - of_node_put(np); of_node_put(cpu); of_node_put(codec); of_node_put(platform); +err_put_np: + of_node_put(np); return ret; } EXPORT_SYMBOL(qcom_snd_parse_of);
There are two issues in this function. 1) We can't drop the refrences on "cpu", "codec" and "platform" before we take the reference. This doesn't cause a problem on the first iteration because those pointers start as NULL so the of_node_put() is a no-op. But on the subsequent iterations, it will lead to a use after free. 2) If the devm_kzalloc() allocation failed then the code returned directly instead of cleaning up. Fixes: c1e6414cdc37 ("ASoC: qcom: common: Fix refcount imbalance on error") Fixes: 1e36ea360ab9 ("ASoC: qcom: common: use modern dai_link style") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> --- sound/soc/qcom/common.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-)