lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Fri, 14 Oct 2022 16:46:58 +0200 From: Ard Biesheuvel <ardb@...nel.org> To: "Guilherme G. Piccoli" <gpiccoli@...lia.com> Cc: linux-kernel@...r.kernel.org, linux-hardening@...r.kernel.org, linux-fsdevel@...r.kernel.org, linux-efi@...r.kernel.org, kernel-dev@...lia.com, kernel@...ccoli.net, keescook@...omium.org, anton@...msg.org, ccross@...roid.com, tony.luck@...el.com Subject: Re: [PATCH V2 1/3] pstore: Alert on backend write error On Thu, 13 Oct 2022 at 23:11, Guilherme G. Piccoli <gpiccoli@...lia.com> wrote: > > The pstore dump function doesn't alert at all on errors - despite > pstore is usually a last resource and if it fails users won't be > able to read the kernel log, this is not the case for server users > with serial access, for example. > > So, let's at least attempt to inform such advanced users on the first > backend writing error detected during the kmsg dump - this is also > very useful for pstore debugging purposes. > > Signed-off-by: Guilherme G. Piccoli <gpiccoli@...lia.com> Acked-by: Ard Biesheuvel <ardb@...nel.org> > --- > > > V2: > - Show error message late, outside of the critical region > (thanks Kees for the idea!). > > > fs/pstore/platform.c | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c > index 06c2c66af332..cbc0b468c1ab 100644 > --- a/fs/pstore/platform.c > +++ b/fs/pstore/platform.c > @@ -393,6 +393,7 @@ static void pstore_dump(struct kmsg_dumper *dumper, > const char *why; > unsigned int part = 1; > unsigned long flags = 0; > + int saved_ret = 0; > int ret; > > why = kmsg_dump_reason_str(reason); > @@ -463,12 +464,21 @@ static void pstore_dump(struct kmsg_dumper *dumper, > if (ret == 0 && reason == KMSG_DUMP_OOPS) { > pstore_new_entry = 1; > pstore_timer_kick(); > + } else { > + /* Preserve only the first non-zero returned value. */ > + if (!saved_ret) > + saved_ret = ret; > } > > total += record.size; > part++; > } > spin_unlock_irqrestore(&psinfo->buf_lock, flags); > + > + if (saved_ret) { > + pr_err_once("backend (%s) writing error (%d)\n", psinfo->name, > + saved_ret); > + } > } > > static struct kmsg_dumper pstore_dumper = { > -- > 2.38.0 >
Powered by blists - more mailing lists