4.19-stable review patch. If anyone has any objections, please let me know.
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From: Bui Quang Minh minhquangbui99@gmail.com
[ Upstream commit 8c34096c7fdf272fd4c0c37fe411cd2e3ed0ee9f ]
Currently, we allocate a nbytes-sized kernel buffer and copy nbytes from userspace to that buffer. Later, we use sscanf on this buffer but we don't ensure that the string is terminated inside the buffer, this can lead to OOB read when using sscanf. Fix this issue by using memdup_user_nul instead of memdup_user.
Fixes: 7afc5dbde091 ("bna: Add debugfs interface.") Signed-off-by: Bui Quang Minh minhquangbui99@gmail.com Link: https://lore.kernel.org/r/20240424-fix-oob-read-v2-2-f1f1b53a10f4@gmail.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/brocade/bna/bnad_debugfs.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/brocade/bna/bnad_debugfs.c b/drivers/net/ethernet/brocade/bna/bnad_debugfs.c index 933799be0471b..d549fdb6bbe2e 100644 --- a/drivers/net/ethernet/brocade/bna/bnad_debugfs.c +++ b/drivers/net/ethernet/brocade/bna/bnad_debugfs.c @@ -320,7 +320,7 @@ bnad_debugfs_write_regrd(struct file *file, const char __user *buf, void *kern_buf;
/* Copy the user space buf */ - kern_buf = memdup_user(buf, nbytes); + kern_buf = memdup_user_nul(buf, nbytes); if (IS_ERR(kern_buf)) return PTR_ERR(kern_buf);
@@ -380,7 +380,7 @@ bnad_debugfs_write_regwr(struct file *file, const char __user *buf, void *kern_buf;
/* Copy the user space buf */ - kern_buf = memdup_user(buf, nbytes); + kern_buf = memdup_user_nul(buf, nbytes); if (IS_ERR(kern_buf)) return PTR_ERR(kern_buf);