From: Liu ShuoX <shuox.liu@xxxxxxxxx> 3.12-stable review patch. If anyone has any objections, please let me know. =============== commit b0aa931fb84431394d995472d0af2a6c2b61064d upstream. ramoops_get_next_prz get the prz according the paramters. If it get a uninitialized prz, access its members by following persistent_ram_old_size(prz) will cause a NULL pointer crash. Ex: if ftrace_size is 0, fprz will be NULL. Fix it by return NULL in advance. Signed-off-by: Liu ShuoX <shuox.liu@xxxxxxxxx> Acked-by: Kees Cook <keescook@xxxxxxxxxxxx> Signed-off-by: Tony Luck <tony.luck@xxxxxxxxx> Cc: HuKeping <hukeping@xxxxxxxxxx> Signed-off-by: Jiri Slaby <jslaby@xxxxxxx> --- fs/pstore/ram.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c index 808435a9e2e1..fe68d8ac4d3d 100644 --- a/fs/pstore/ram.c +++ b/fs/pstore/ram.c @@ -125,6 +125,8 @@ ramoops_get_next_prz(struct persistent_ram_zone *przs[], uint *c, uint max, return NULL; prz = przs[i]; + if (!prz) + return NULL; /* Update old/shadowed buffer. */ if (update) -- 2.2.2 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html