| Message ID | 8c90be28-67b4-4b0d-a105-034dc72a0b31@stanley.mountain (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | mmc: mmc_test: Fix NULL dereference on allocation failure | expand |
On Tue, 20 Aug 2024 at 10:44, Dan Carpenter <dan.carpenter@linaro.org> wrote: > > If the "test->highmem = alloc_pages()" allocation fails then calling > __free_pages(test->highmem) will result in a NULL dereference. Also > change the error code to -ENOMEM instead of returning success. > > Fixes: 2661081f5ab9 ("mmc_test: highmem tests") > Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org> Applied for fixes, thanks! Kind regards Uffe > --- > This code is from 2008 so it must not be that much of an issue in real > life. > > drivers/mmc/core/mmc_test.c | 9 +++++---- > 1 file changed, 5 insertions(+), 4 deletions(-) > > diff --git a/drivers/mmc/core/mmc_test.c b/drivers/mmc/core/mmc_test.c > index 8f7f587a0025..b7f627a9fdea 100644 > --- a/drivers/mmc/core/mmc_test.c > +++ b/drivers/mmc/core/mmc_test.c > @@ -3125,13 +3125,13 @@ static ssize_t mtf_test_write(struct file *file, const char __user *buf, > test->buffer = kzalloc(BUFFER_SIZE, GFP_KERNEL); > #ifdef CONFIG_HIGHMEM > test->highmem = alloc_pages(GFP_KERNEL | __GFP_HIGHMEM, BUFFER_ORDER); > + if (!test->highmem) { > + count = -ENOMEM; > + goto free_test_buffer; > + } > #endif > > -#ifdef CONFIG_HIGHMEM > - if (test->buffer && test->highmem) { > -#else > if (test->buffer) { > -#endif > mutex_lock(&mmc_test_lock); > mmc_test_run(test, testcase); > mutex_unlock(&mmc_test_lock); > @@ -3139,6 +3139,7 @@ static ssize_t mtf_test_write(struct file *file, const char __user *buf, > > #ifdef CONFIG_HIGHMEM > __free_pages(test->highmem, BUFFER_ORDER); > +free_test_buffer: > #endif > kfree(test->buffer); > kfree(test); > -- > 2.43.0 >
diff --git a/drivers/mmc/core/mmc_test.c b/drivers/mmc/core/mmc_test.c index 8f7f587a0025..b7f627a9fdea 100644 --- a/drivers/mmc/core/mmc_test.c +++ b/drivers/mmc/core/mmc_test.c @@ -3125,13 +3125,13 @@ static ssize_t mtf_test_write(struct file *file, const char __user *buf, test->buffer = kzalloc(BUFFER_SIZE, GFP_KERNEL); #ifdef CONFIG_HIGHMEM test->highmem = alloc_pages(GFP_KERNEL | __GFP_HIGHMEM, BUFFER_ORDER); + if (!test->highmem) { + count = -ENOMEM; + goto free_test_buffer; + } #endif -#ifdef CONFIG_HIGHMEM - if (test->buffer && test->highmem) { -#else if (test->buffer) { -#endif mutex_lock(&mmc_test_lock); mmc_test_run(test, testcase); mutex_unlock(&mmc_test_lock); @@ -3139,6 +3139,7 @@ static ssize_t mtf_test_write(struct file *file, const char __user *buf, #ifdef CONFIG_HIGHMEM __free_pages(test->highmem, BUFFER_ORDER); +free_test_buffer: #endif kfree(test->buffer); kfree(test);
If the "test->highmem = alloc_pages()" allocation fails then calling __free_pages(test->highmem) will result in a NULL dereference. Also change the error code to -ENOMEM instead of returning success. Fixes: 2661081f5ab9 ("mmc_test: highmem tests") Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org> --- This code is from 2008 so it must not be that much of an issue in real life. drivers/mmc/core/mmc_test.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-)