From 0d36496b9756f32fde7e877c6914bf1173a2c811 Mon Sep 17 00:00:00 2001 From: Prateek Sood Date: Wed, 12 Aug 2020 14:51:29 +0530 Subject: [PATCH] BACKPORT: FROMLIST: firmware_loader: fix memory leak for paged buffer vfree() is being called on paged buffer allocated using alloc_page() and mapped using vmap(). Freeing of pages in __vunmap() relies on nr_pages of struct vm_struct. vmap() does not update nr_pages. Bug: 166705104 Link: https://lore.kernel.org/patchwork/patch/1292695/ Change-Id: I8d9610d89f2936edc01b977ceba1853b41d5c249 Signed-off-by: Prateek Sood --- drivers/base/firmware_loader/firmware.h | 2 ++ drivers/base/firmware_loader/main.c | 17 +++++++++++------ 2 files changed, 13 insertions(+), 6 deletions(-) diff --git a/drivers/base/firmware_loader/firmware.h b/drivers/base/firmware_loader/firmware.h index 7ecd590e67fe..9bef6c35f344 100644 --- a/drivers/base/firmware_loader/firmware.h +++ b/drivers/base/firmware_loader/firmware.h @@ -139,10 +139,12 @@ int assign_fw(struct firmware *fw, struct device *device, void fw_free_paged_buf(struct fw_priv *fw_priv); int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed); int fw_map_paged_buf(struct fw_priv *fw_priv); +bool fw_is_paged_buf(struct fw_priv *fw_priv); #else static inline void fw_free_paged_buf(struct fw_priv *fw_priv) {} static inline int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed) { return -ENXIO; } static inline int fw_map_paged_buf(struct fw_priv *fw_priv) { return -ENXIO; } +static inline bool fw_is_paged_buf(struct fw_priv *fw_priv) { return false; } #endif #endif /* __FIRMWARE_LOADER_H */ diff --git a/drivers/base/firmware_loader/main.c b/drivers/base/firmware_loader/main.c index 1c9f03514a47..cdcf4ea34d5f 100644 --- a/drivers/base/firmware_loader/main.c +++ b/drivers/base/firmware_loader/main.c @@ -252,9 +252,11 @@ static void __free_fw_priv(struct kref *ref) list_del(&fw_priv->list); spin_unlock(&fwc->lock); - fw_free_paged_buf(fw_priv); /* free leftover pages */ - if (!fw_priv->allocated_size) + if (fw_is_paged_buf(fw_priv)) + fw_free_paged_buf(fw_priv); /* free leftover pages */ + else if (!fw_priv->allocated_size) vfree(fw_priv->data); + kfree_const(fw_priv->fw_name); kfree(fw_priv); } @@ -268,6 +270,11 @@ static void free_fw_priv(struct fw_priv *fw_priv) } #ifdef CONFIG_FW_LOADER_PAGED_BUF +bool fw_is_paged_buf(struct fw_priv *fw_priv) +{ + return fw_priv->is_paged_buf; +} + void fw_free_paged_buf(struct fw_priv *fw_priv) { int i; @@ -275,6 +282,8 @@ void fw_free_paged_buf(struct fw_priv *fw_priv) if (!fw_priv->pages) return; + vunmap(fw_priv->data); + for (i = 0; i < fw_priv->nr_pages; i++) __free_page(fw_priv->pages[i]); kvfree(fw_priv->pages); @@ -328,10 +337,6 @@ int fw_map_paged_buf(struct fw_priv *fw_priv) if (!fw_priv->data) return -ENOMEM; - /* page table is no longer needed after mapping, let's free */ - kvfree(fw_priv->pages); - fw_priv->pages = NULL; - return 0; } #endif