public inbox for glibc-cvs@sourceware.org help / color / mirror / Atom feed
From: DJ Delorie <dj@sourceware.org> To: glibc-cvs@sourceware.org Subject: [glibc/release/2.35/master] nss: handle stat failure in check_reload_and_get (BZ #28752) Date: Tue, 14 Jun 2022 02:59:00 +0000 (GMT) [thread overview] Message-ID: <20220614025900.F041E386DC55@sourceware.org> (raw) https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=b6aade18a7e5719c942aa2da6cf3157aca993fa4 commit b6aade18a7e5719c942aa2da6cf3157aca993fa4 Author: Sam James <sam@gentoo.org> Date: Sun Jun 5 04:57:10 2022 +0100 nss: handle stat failure in check_reload_and_get (BZ #28752) Skip the chroot test if the database isn't loaded correctly (because the chroot test uses some existing DB state). The __stat64_time64 -> fstatat call can fail if running under an (aggressive) seccomp filter, like Firefox seems to use. This manifested in a crash when using glib built with FAM support with such a Firefox build. Suggested-by: DJ Delorie <dj@redhat.com> Signed-off-by: Sam James <sam@gentoo.org> Reviewed-by: DJ Delorie <dj@redhat.com> (cherry picked from commit ace9e3edbca62d978b1e8f392d8a5d78500272d9) Diff: --- nss/nss_database.c | 39 ++++++++++++++++++++++++--------------- 1 file changed, 24 insertions(+), 15 deletions(-) diff --git a/nss/nss_database.c b/nss/nss_database.c index d56c5b798d..f2ed2f2c25 100644 --- a/nss/nss_database.c +++ b/nss/nss_database.c @@ -420,23 +420,32 @@ nss_database_check_reload_and_get (struct nss_database_state *local, return true; } - /* Before we reload, verify that "/" hasn't changed. We assume that - errors here are very unlikely, but the chance that we're entering - a container is also very unlikely, so we err on the side of both - very unlikely things not happening at the same time. */ - if (__stat64_time64 ("/", &str) != 0 - || (local->root_ino != 0 - && (str.st_ino != local->root_ino - || str.st_dev != local->root_dev))) + int stat_rv = __stat64_time64 ("/", &str); + + if (local->data.services[database_index] != NULL) { - /* Change detected; disable reloading and return current state. */ - atomic_store_release (&local->data.reload_disabled, 1); - *result = local->data.services[database_index]; - __libc_lock_unlock (local->lock); - return true; + /* Before we reload, verify that "/" hasn't changed. We assume that + errors here are very unlikely, but the chance that we're entering + a container is also very unlikely, so we err on the side of both + very unlikely things not happening at the same time. */ + if (stat_rv != 0 + || (local->root_ino != 0 + && (str.st_ino != local->root_ino + || str.st_dev != local->root_dev))) + { + /* Change detected; disable reloading and return current state. */ + atomic_store_release (&local->data.reload_disabled, 1); + *result = local->data.services[database_index]; + __libc_lock_unlock (local->lock); + return true; + } + } + if (stat_rv == 0) + { + local->root_ino = str.st_ino; + local->root_dev = str.st_dev; } - local->root_ino = str.st_ino; - local->root_dev = str.st_dev; + __libc_lock_unlock (local->lock); /* Avoid overwriting the global configuration until we have loaded
reply other threads:[~2022-06-14 2:59 UTC|newest] Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20220614025900.F041E386DC55@sourceware.org \ --to=dj@sourceware.org \ --cc=glibc-cvs@sourceware.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).