Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-25 13:41:51 +00:00
Code Issues Packages Projects Releases Wiki Activity

driver core: Fix size calculation of symlink name for devlink_(add|remove)_symlinks()

Browse Source 
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 <quic_zijuhu@quicinc.com>
Link: https://lore.kernel.org/r/20240712-devlink_fix-v3-1-fa1c5172ffc7@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Zijun Hu 2024-07-12 19:52:31 +08:00 committed by Greg Kroah-Hartman
parent 8400291e28
commit 4ea5e9deda
1 changed files with 6 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
drivers/base/core.c
View File

@ -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");