From 63f637309baadf81a095f2653e3b807d4b5814b9 Mon Sep 17 00:00:00 2001 From: Jiasheng Jiang Date: Fri, 23 Jun 2023 10:27:06 +0800 Subject: [PATCH] pstore/platform: Add check for kstrdup [ Upstream commit a19d48f7c5d57c0f0405a7d4334d1d38fe9d3c1c ] Add check for the return value of kstrdup() and return the error if it fails in order to avoid NULL pointer dereference. Fixes: 563ca40ddf40 ("pstore/platform: Switch pstore_info::name to const") Signed-off-by: Jiasheng Jiang Link: https://lore.kernel.org/r/20230623022706.32125-1-jiasheng@iscas.ac.cn Signed-off-by: Kees Cook Signed-off-by: Sasha Levin --- fs/pstore/platform.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c index 0c034ea..7787fb5 100644 --- a/fs/pstore/platform.c +++ b/fs/pstore/platform.c @@ -561,6 +561,8 @@ out: */ int pstore_register(struct pstore_info *psi) { + char *new_backend; + if (backend && strcmp(backend, psi->name)) { pr_warn("ignoring unexpected backend '%s'\n", psi->name); return -EPERM; @@ -580,11 +582,16 @@ int pstore_register(struct pstore_info *psi) return -EINVAL; } + new_backend = kstrdup(psi->name, GFP_KERNEL); + if (!new_backend) + return -ENOMEM; + mutex_lock(&psinfo_lock); if (psinfo) { pr_warn("backend '%s' already loaded: ignoring '%s'\n", psinfo->name, psi->name); mutex_unlock(&psinfo_lock); + kfree(new_backend); return -EBUSY; } @@ -617,7 +624,7 @@ int pstore_register(struct pstore_info *psi) * Update the module parameter backend, so it is visible * through /sys/module/pstore/parameters/backend */ - backend = kstrdup(psi->name, GFP_KERNEL); + backend = new_backend; pr_info("Registered %s as persistent store backend\n", psi->name); -- 2.7.4