From: Zijun Hu Date: Fri, 12 Jul 2024 11:52:31 +0000 (+0800) Subject: driver core: Fix size calculation of symlink name for devlink_(add|remove)_symlinks() X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=4ea5e9deda3f4cbd471d29e6e99106e51be19c86;p=users%2Fjedix%2Flinux-maple.git driver core: Fix size calculation of symlink name for devlink_(add|remove)_symlinks() devlink_(add|remove)_symlinks() kzalloc() memory to save symlink name for both supplier and consumer, but do not explicitly take into account consumer's prefix "consumer:", so cause disadvantages listed below: 1) it seems wrong for the algorithm to calculate memory size 2) readers maybe need to count characters one by one of both prefix strings to confirm calculated memory size 3) it is relatively easy to introduce new bug if either prefix string is modified in future solved by taking into account consumer's prefix as well. Signed-off-by: Zijun Hu Link: https://lore.kernel.org/r/20240712-devlink_fix-v3-1-fa1c5172ffc7@quicinc.com Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/base/core.c b/drivers/base/core.c index 730cae66607c..3e82eaba4932 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -572,7 +572,11 @@ static int devlink_add_symlinks(struct device *dev) len = max(strlen(dev_bus_name(sup)) + strlen(dev_name(sup)), strlen(dev_bus_name(con)) + strlen(dev_name(con))); len += strlen(":"); - len += strlen("supplier:") + 1; + /* + * we kzalloc() memory for symlink name of both supplier and + * consumer, so explicitly take into account both prefix. + */ + len += max(strlen("supplier:"), strlen("consumer:")) + 1; buf = kzalloc(len, GFP_KERNEL); if (!buf) return -ENOMEM; @@ -623,7 +627,7 @@ static void devlink_remove_symlinks(struct device *dev) len = max(strlen(dev_bus_name(sup)) + strlen(dev_name(sup)), strlen(dev_bus_name(con)) + strlen(dev_name(con))); len += strlen(":"); - len += strlen("supplier:") + 1; + len += max(strlen("supplier:"), strlen("consumer:")) + 1; buf = kzalloc(len, GFP_KERNEL); if (!buf) { WARN(1, "Unable to properly free device link symlinks!\n");