diff options
| author | Vadym Kochan <vadym.kochan@plvision.eu> | 2020-09-23 23:44:56 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-09-27 14:25:48 +0200 |
| commit | fc9eec4d643597cf4cb2fef17d48110e677610da (patch) | |
| tree | 1fd23e86d6682d06b3720a601d835f7d4c76651d /drivers/nvmem/core.c | |
| parent | 709ec3f7fc5773ac4aa6fb22c3f0ac8103c674db (diff) | |
nvmem: core: fix possibly memleak when use nvmem_cell_info_to_nvmem_cell()
Fix missing 'kfree_const(cell->name)' when call to
nvmem_cell_info_to_nvmem_cell() in several places:
* after nvmem_cell_info_to_nvmem_cell() failed during
nvmem_add_cells()
* during nvmem_device_cell_{read,write} when cell->name is
kstrdup'ed() without calling kfree_const() at the end, but
really there is no reason to do that 'dup, because the cell
instance is allocated on the stack for some short period to be
read/write without exposing it to the caller.
So the new nvmem_cell_info_to_nvmem_cell_nodup() helper is introduced
which is used to convert cell_info -> cell without name duplication as
a lighweight version of nvmem_cell_info_to_nvmem_cell().
Fixes: e2a5402ec7c6 ("nvmem: Add nvmem_device based consumer apis.")
Reviewed-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Vadym Kochan <vadym.kochan@plvision.eu>
Link: https://lore.kernel.org/r/20200923204456.14032-1-vadym.kochan@plvision.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/nvmem/core.c')
| -rw-r--r-- | drivers/nvmem/core.c | 33 |
1 files changed, 24 insertions, 9 deletions
diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c index ab57289fe593..a09ff8409f60 100644 --- a/drivers/nvmem/core.c +++ b/drivers/nvmem/core.c @@ -361,16 +361,14 @@ static void nvmem_cell_add(struct nvmem_cell *cell) blocking_notifier_call_chain(&nvmem_notifier, NVMEM_CELL_ADD, cell); } -static int nvmem_cell_info_to_nvmem_cell(struct nvmem_device *nvmem, - const struct nvmem_cell_info *info, - struct nvmem_cell *cell) +static int nvmem_cell_info_to_nvmem_cell_nodup(struct nvmem_device *nvmem, + const struct nvmem_cell_info *info, + struct nvmem_cell *cell) { cell->nvmem = nvmem; cell->offset = info->offset; cell->bytes = info->bytes; - cell->name = kstrdup_const(info->name, GFP_KERNEL); - if (!cell->name) - return -ENOMEM; + cell->name = info->name; cell->bit_offset = info->bit_offset; cell->nbits = info->nbits; @@ -382,13 +380,30 @@ static int nvmem_cell_info_to_nvmem_cell(struct nvmem_device *nvmem, if (!IS_ALIGNED(cell->offset, nvmem->stride)) { dev_err(&nvmem->dev, "cell %s unaligned to nvmem stride %d\n", - cell->name, nvmem->stride); + cell->name ?: "<unknown>", nvmem->stride); return -EINVAL; } return 0; } +static int nvmem_cell_info_to_nvmem_cell(struct nvmem_device *nvmem, + const struct nvmem_cell_info *info, + struct nvmem_cell *cell) +{ + int err; + + err = nvmem_cell_info_to_nvmem_cell_nodup(nvmem, info, cell); + if (err) + return err; + + cell->name = kstrdup_const(info->name, GFP_KERNEL); + if (!cell->name) + return -ENOMEM; + + return 0; +} + /** * nvmem_add_cells() - Add cell information to an nvmem device * @@ -1463,7 +1478,7 @@ ssize_t nvmem_device_cell_read(struct nvmem_device *nvmem, if (!nvmem) return -EINVAL; - rc = nvmem_cell_info_to_nvmem_cell(nvmem, info, &cell); + rc = nvmem_cell_info_to_nvmem_cell_nodup(nvmem, info, &cell); if (rc) return rc; @@ -1493,7 +1508,7 @@ int nvmem_device_cell_write(struct nvmem_device *nvmem, if (!nvmem) return -EINVAL; - rc = nvmem_cell_info_to_nvmem_cell(nvmem, info, &cell); + rc = nvmem_cell_info_to_nvmem_cell_nodup(nvmem, info, &cell); if (rc) return rc; |