[PATCH 5.4 130/134] mmc: sdio: Fix several potential memory leaks in mmc_sdio_init_card()

From: Greg Kroah-Hartman
Date: Tue Jun 16 2020 - 12:15:42 EST


From: Ulf Hansson <ulf.hansson@xxxxxxxxxx>

commit a94a59f43749b4f8cd81b8be87c95f9ef898d19d upstream.

Over the years, the code in mmc_sdio_init_card() has grown to become quite
messy. Unfortunate this has also lead to that several paths are leaking
memory in form of an allocated struct mmc_card, which includes additional
data, such as initialized struct device for example.

Unfortunate, it's a too complex task find each offending commit. Therefore,
this change fixes all memory leaks at once.

Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20200430091640.455-3-ulf.hansson@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/mmc/core/sdio.c | 58 ++++++++++++++++++++++--------------------------
1 file changed, 27 insertions(+), 31 deletions(-)

--- a/drivers/mmc/core/sdio.c
+++ b/drivers/mmc/core/sdio.c
@@ -584,7 +584,7 @@ try_again:
*/
err = mmc_send_io_op_cond(host, ocr, &rocr);
if (err)
- goto err;
+ return err;

/*
* For SPI, enable CRC as appropriate.
@@ -592,17 +592,15 @@ try_again:
if (mmc_host_is_spi(host)) {
err = mmc_spi_set_crc(host, use_spi_crc);
if (err)
- goto err;
+ return err;
}

/*
* Allocate card structure.
*/
card = mmc_alloc_card(host, NULL);
- if (IS_ERR(card)) {
- err = PTR_ERR(card);
- goto err;
- }
+ if (IS_ERR(card))
+ return PTR_ERR(card);

if ((rocr & R4_MEMORY_PRESENT) &&
mmc_sd_get_cid(host, ocr & rocr, card->raw_cid, NULL) == 0) {
@@ -610,19 +608,15 @@ try_again:

if (oldcard && (oldcard->type != MMC_TYPE_SD_COMBO ||
memcmp(card->raw_cid, oldcard->raw_cid, sizeof(card->raw_cid)) != 0)) {
- mmc_remove_card(card);
- pr_debug("%s: Perhaps the card was replaced\n",
- mmc_hostname(host));
- return -ENOENT;
+ err = -ENOENT;
+ goto mismatch;
}
} else {
card->type = MMC_TYPE_SDIO;

if (oldcard && oldcard->type != MMC_TYPE_SDIO) {
- mmc_remove_card(card);
- pr_debug("%s: Perhaps the card was replaced\n",
- mmc_hostname(host));
- return -ENOENT;
+ err = -ENOENT;
+ goto mismatch;
}
}

@@ -677,7 +671,7 @@ try_again:
if (!oldcard && card->type == MMC_TYPE_SD_COMBO) {
err = mmc_sd_get_csd(host, card);
if (err)
- return err;
+ goto remove;

mmc_decode_cid(card);
}
@@ -704,7 +698,12 @@ try_again:
mmc_set_timing(card->host, MMC_TIMING_SD_HS);
}

- goto finish;
+ if (oldcard)
+ mmc_remove_card(card);
+ else
+ host->card = card;
+
+ return 0;
}

/*
@@ -730,16 +729,14 @@ try_again:
goto remove;

if (oldcard) {
- int same = (card->cis.vendor == oldcard->cis.vendor &&
- card->cis.device == oldcard->cis.device);
- mmc_remove_card(card);
- if (!same) {
- pr_debug("%s: Perhaps the card was replaced\n",
- mmc_hostname(host));
- return -ENOENT;
+ if (card->cis.vendor == oldcard->cis.vendor &&
+ card->cis.device == oldcard->cis.device) {
+ mmc_remove_card(card);
+ card = oldcard;
+ } else {
+ err = -ENOENT;
+ goto mismatch;
}
-
- card = oldcard;
}
card->ocr = ocr_card;
mmc_fixup_device(card, sdio_fixup_methods);
@@ -800,16 +797,15 @@ try_again:
err = -EINVAL;
goto remove;
}
-finish:
- if (!oldcard)
- host->card = card;
+
+ host->card = card;
return 0;

+mismatch:
+ pr_debug("%s: Perhaps the card was replaced\n", mmc_hostname(host));
remove:
- if (!oldcard)
+ if (oldcard != card)
mmc_remove_card(card);
-
-err:
return err;
}