From: Yue Hu Date: Thu, 31 Jan 2019 10:12:46 +0000 (+0800) Subject: pstore: Avoid writing records with zero size X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=4c6c4d34536744f2c9e171ef5bb548a06a525501;p=linux.git pstore: Avoid writing records with zero size Sometimes pstore_console_write() will write records with zero size to persistent ram zone, which is unnecessary. It will only increase resource consumption. Also adjust ramoops_write_kmsg_hdr() to have same logic if memory allocation fails. Signed-off-by: Yue Hu Signed-off-by: Kees Cook --- diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c index 2d1066ed3c28e..75887a269b642 100644 --- a/fs/pstore/platform.c +++ b/fs/pstore/platform.c @@ -501,6 +501,9 @@ static void pstore_console_write(struct console *con, const char *s, unsigned c) { struct pstore_record record; + if (!c) + return; + pstore_record_init(&record, psinfo); record.type = PSTORE_TYPE_CONSOLE; diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c index 1adb5e35c004c..b2471d430048a 100644 --- a/fs/pstore/ram.c +++ b/fs/pstore/ram.c @@ -352,8 +352,10 @@ static size_t ramoops_write_kmsg_hdr(struct persistent_ram_zone *prz, (time64_t)record->time.tv_sec, record->time.tv_nsec / 1000, record->compressed ? 'C' : 'D'); - WARN_ON_ONCE(!hdr); - len = hdr ? strlen(hdr) : 0; + if (WARN_ON_ONCE(!hdr)) + return 0; + + len = strlen(hdr); persistent_ram_write(prz, hdr, len); kfree(hdr);