The patch titled Subject: zram: correctly handle all next_arg() cases has been added to the -mm mm-unstable branch. Its filename is zram-correctly-handle-all-next_arg-cases.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/zram-correctly-handle-all-next_arg-cases.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx> Subject: zram: correctly handle all next_arg() cases Date: Tue, 3 Jan 2023 12:01:19 +0900 When supplied buffer does not have assignment sign next_arg() sets `val` pointer to NULL, so we cannot dereference it. Add a NULL pointer test to handle `param` case, in addition to `*val` test, which handles cases when param has no value assigned to it: `param=`. Link: https://lkml.kernel.org/r/20230103030119.1496358-1-senozhatsky@xxxxxxxxxxxx Signed-off-by: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx> Cc: Minchan Kim <minchan@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- drivers/block/zram/zram_drv.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/block/zram/zram_drv.c~zram-correctly-handle-all-next_arg-cases +++ a/drivers/block/zram/zram_drv.c @@ -1140,7 +1140,7 @@ static ssize_t recomp_algorithm_store(st while (*args) { args = next_arg(args, ¶m, &val); - if (!*val) + if (!val || !*val) return -EINVAL; if (!strcmp(param, "algo")) { @@ -1824,7 +1824,7 @@ static ssize_t recompress_store(struct d while (*args) { args = next_arg(args, ¶m, &val); - if (!*val) + if (!val || !*val) return -EINVAL; if (!strcmp(param, "type")) { _ Patches currently in -mm which might be from senozhatsky@xxxxxxxxxxxx are zram-correctly-handle-all-next_arg-cases.patch