From: Huang Yiwei <hyi...@codeaurora.org> In a scenario of panic, when we use DRAM to store log instead of persistant storage and during warm reset when we copy these data outside of ram. Missing check on prz->start(write position) can cause crash because it can be any value and can point outside the mapped region. So add the start check to avoid.
Signed-off-by: Huang Yiwei <hyi...@codeaurora.org> Signed-off-by: Mukesh Ojha <mo...@codeaurora.org> --- change in v2: - this is on top of first patchset. fs/pstore/ram_core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/pstore/ram_core.c b/fs/pstore/ram_core.c index 0da012f..a15748a 100644 --- a/fs/pstore/ram_core.c +++ b/fs/pstore/ram_core.c @@ -514,7 +514,7 @@ static int persistent_ram_post_init(struct persistent_ram_zone *prz, u32 sig, sig ^= PERSISTENT_RAM_SIG; if (prz->buffer->sig == sig) { - if (buffer_size(prz) == 0) { + if (buffer_size(prz) == 0 && buffer_start(prz) == 0) { pr_debug("found existing empty buffer\n"); return 0; } -- Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project