This is a note to let you know that I've just added the patch titled pstore/platform: Add check for kstrdup to the 6.5-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: pstore-platform-add-check-for-kstrdup.patch and it can be found in the queue-6.5 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit c8c32bbc20d669914aedef72df1b01b6c3118e4b Author: Jiasheng Jiang <jiasheng@xxxxxxxxxxx> Date: Fri Jun 23 10:27:06 2023 +0800 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 <jiasheng@xxxxxxxxxxx> Link: https://lore.kernel.org/r/20230623022706.32125-1-jiasheng@xxxxxxxxxxx Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c index cbc0b468c1ab6..15cefe268ffd8 100644 --- a/fs/pstore/platform.c +++ b/fs/pstore/platform.c @@ -573,6 +573,8 @@ static int pstore_write_user_compat(struct pstore_record *record, */ int pstore_register(struct pstore_info *psi) { + char *new_backend; + if (backend && strcmp(backend, psi->name)) { pr_warn("backend '%s' already in use: ignoring '%s'\n", backend, psi->name); @@ -593,11 +595,16 @@ 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; } @@ -630,7 +637,7 @@ 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);