From be308d68785b205e483b3a0c61ba3a82da468f2c Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Thu, 2 Feb 2023 16:28:20 +0100 Subject: [PATCH] USB: dwc3: fix memory leak with using debugfs_lookup() When calling debugfs_lookup() the result must have dput() called on it, otherwise the memory will leak over time. To make things simpler, just call debugfs_lookup_and_remove() instead which handles all of the logic at once. Note, the root dentry for the debugfs directory for the device needs to be saved so we don't have to keep looking it up, which required a bit more refactoring to properly create and remove it when needed. Reported-by: Bruce Chen Reported-by: Cixi Geng Tested-by: Cixi Geng Acked-by: Thinh Nguyen Link: https://lore.kernel.org/r/20230202152820.2409908-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman --- drivers/usb/dwc3/core.h | 2 ++ drivers/usb/dwc3/debug.h | 3 +++ drivers/usb/dwc3/debugfs.c | 19 ++++++++----------- drivers/usb/dwc3/gadget.c | 4 +--- 4 files changed, 14 insertions(+), 14 deletions(-) diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h index 8f9959b..582ebd9 100644 --- a/drivers/usb/dwc3/core.h +++ b/drivers/usb/dwc3/core.h @@ -1117,6 +1117,7 @@ struct dwc3_scratchpad_array { * address. * @num_ep_resized: carries the current number endpoints which have had its tx * fifo resized. + * @debug_root: root debugfs directory for this device to put its files in. */ struct dwc3 { struct work_struct drd_work; @@ -1332,6 +1333,7 @@ struct dwc3 { int max_cfg_eps; int last_fifo_depth; int num_ep_resized; + struct dentry *debug_root; }; #define INCRX_BURST_MODE 0 diff --git a/drivers/usb/dwc3/debug.h b/drivers/usb/dwc3/debug.h index 48b44b8..8bb2c9e 100644 --- a/drivers/usb/dwc3/debug.h +++ b/drivers/usb/dwc3/debug.h @@ -414,11 +414,14 @@ static inline const char *dwc3_gadget_generic_cmd_status_string(int status) #ifdef CONFIG_DEBUG_FS extern void dwc3_debugfs_create_endpoint_dir(struct dwc3_ep *dep); +extern void dwc3_debugfs_remove_endpoint_dir(struct dwc3_ep *dep); extern void dwc3_debugfs_init(struct dwc3 *d); extern void dwc3_debugfs_exit(struct dwc3 *d); #else static inline void dwc3_debugfs_create_endpoint_dir(struct dwc3_ep *dep) { } +static inline void dwc3_debugfs_remove_endpoint_dir(struct dwc3_ep *dep) +{ } static inline void dwc3_debugfs_init(struct dwc3 *d) { } static inline void dwc3_debugfs_exit(struct dwc3 *d) diff --git a/drivers/usb/dwc3/debugfs.c b/drivers/usb/dwc3/debugfs.c index f2b7675..850df0e 100644 --- a/drivers/usb/dwc3/debugfs.c +++ b/drivers/usb/dwc3/debugfs.c @@ -873,27 +873,23 @@ static const struct dwc3_ep_file_map dwc3_ep_file_map[] = { { "GDBGEPINFO", &dwc3_ep_info_register_fops, }, }; -static void dwc3_debugfs_create_endpoint_files(struct dwc3_ep *dep, - struct dentry *parent) +void dwc3_debugfs_create_endpoint_dir(struct dwc3_ep *dep) { + struct dentry *dir; int i; + dir = debugfs_create_dir(dep->name, dep->dwc->debug_root); for (i = 0; i < ARRAY_SIZE(dwc3_ep_file_map); i++) { const struct file_operations *fops = dwc3_ep_file_map[i].fops; const char *name = dwc3_ep_file_map[i].name; - debugfs_create_file(name, 0444, parent, dep, fops); + debugfs_create_file(name, 0444, dir, dep, fops); } } -void dwc3_debugfs_create_endpoint_dir(struct dwc3_ep *dep) +void dwc3_debugfs_remove_endpoint_dir(struct dwc3_ep *dep) { - struct dentry *dir; - struct dentry *root; - - root = debugfs_lookup(dev_name(dep->dwc->dev), usb_debug_root); - dir = debugfs_create_dir(dep->name, root); - dwc3_debugfs_create_endpoint_files(dep, dir); + debugfs_lookup_and_remove(dep->name, dep->dwc->debug_root); } void dwc3_debugfs_init(struct dwc3 *dwc) @@ -911,6 +907,7 @@ void dwc3_debugfs_init(struct dwc3 *dwc) dwc->regset->base = dwc->regs - DWC3_GLOBALS_REGS_START; root = debugfs_create_dir(dev_name(dwc->dev), usb_debug_root); + dwc->debug_root = root; debugfs_create_regset32("regdump", 0444, root, dwc->regset); debugfs_create_file("lsp_dump", 0644, root, dwc, &dwc3_lsp_fops); @@ -929,6 +926,6 @@ void dwc3_debugfs_init(struct dwc3 *dwc) void dwc3_debugfs_exit(struct dwc3 *dwc) { - debugfs_remove(debugfs_lookup(dev_name(dwc->dev), usb_debug_root)); + debugfs_lookup_and_remove(dev_name(dwc->dev), usb_debug_root); kfree(dwc->regset); } diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index 89dcfac..3c63fa9 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -3194,9 +3194,7 @@ static void dwc3_gadget_free_endpoints(struct dwc3 *dwc) list_del(&dep->endpoint.ep_list); } - debugfs_remove_recursive(debugfs_lookup(dep->name, - debugfs_lookup(dev_name(dep->dwc->dev), - usb_debug_root))); + dwc3_debugfs_remove_endpoint_dir(dep); kfree(dep); } } -- 2.7.4