From 4965b8cd1bc1ffb017e5c58e622da82b55e49414 Mon Sep 17 00:00:00 2001 From: Prateek Sood Date: Fri, 21 Aug 2020 02:27:50 +0530 Subject: [PATCH] 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 vfree() relies on nr_pages of struct vm_struct. vmap() does not update nr_pages. It can lead to memory leaks. Fixes: ddaf29fd9bb6 ("firmware: Free temporary page table after vmapping") Signed-off-by: Prateek Sood Reviewed-by: Takashi Iwai Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/1597957070-27185-1-git-send-email-prsood@codeaurora.org Signed-off-by: Greg Kroah-Hartman --- 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 933e2192fbe8..d08efc77cf16 100644 --- a/drivers/base/firmware_loader/firmware.h +++ b/drivers/base/firmware_loader/firmware.h @@ -142,10 +142,12 @@ int assign_fw(struct firmware *fw, struct device *device, u32 opt_flags); 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 9da0c9d5f538..63b9714a0154 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); + 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