From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from firstgate.proxmox.com (firstgate.proxmox.com [IPv6:2a01:7e0:0:424::9]) by lore.proxmox.com (Postfix) with ESMTPS id 78C1C1FF13F for ; Thu, 26 Mar 2026 09:50:35 +0100 (CET) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id D38888852; Thu, 26 Mar 2026 09:50:56 +0100 (CET) Message-ID: Date: Thu, 26 Mar 2026 09:50:49 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH proxmox-backup] fix #5247: relative paths in exclude patterns. To: Christian Ebner , pbs-devel@lists.proxmox.com References: <20260323153202.76874-1-m.federanko@proxmox.com> <21976801-5b8e-4690-b1a7-b8d769e445cf@proxmox.com> Content-Language: en-US From: Manuel Federanko In-Reply-To: <21976801-5b8e-4690-b1a7-b8d769e445cf@proxmox.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Bm-Milter-Handled: 55990f41-d878-4baa-be0a-ee34c49e34d2 X-Bm-Transport-Timestamp: 1774515001807 X-SPAM-LEVEL: Spam detection results: 0 AWL 0.901 Adjusted score from AWL reputation of From: address BAYES_00 -1.9 Bayes spam probability is 0 to 1% DMARC_MISSING 0.1 Missing DMARC policy KAM_DMARC_STATUS 0.01 Test Rule for DKIM or SPF Failure with Strict Alignment RCVD_IN_VALIDITY_CERTIFIED_BLOCKED 0.001 ADMINISTRATOR NOTICE: The query to Validity was blocked. See https://knowledge.validity.com/hc/en-us/articles/20961730681243 for more information. RCVD_IN_VALIDITY_RPBL_BLOCKED 0.001 ADMINISTRATOR NOTICE: The query to Validity was blocked. See https://knowledge.validity.com/hc/en-us/articles/20961730681243 for more information. RCVD_IN_VALIDITY_SAFE_BLOCKED 0.001 ADMINISTRATOR NOTICE: The query to Validity was blocked. See https://knowledge.validity.com/hc/en-us/articles/20961730681243 for more information. SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record Message-ID-Hash: JPOYMNP2BKAI2VUQGHAIKI6FGL2JS63J X-Message-ID-Hash: JPOYMNP2BKAI2VUQGHAIKI6FGL2JS63J X-MailFrom: m.federanko@proxmox.com X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; loop; banned-address; emergency; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header X-Mailman-Version: 3.3.10 Precedence: list List-Id: Proxmox Backup Server development discussion List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: Hi! thanks for your input, I will incorporate the changes in v2. On 2026-03-25 6:04 PM, Christian Ebner wrote: > Hi, thanks for the patch! A few high level comments, no full in detail > review yet. > > On 3/23/26 4:31 PM, Manuel Federanko wrote: >> Patterns which start with ./ or for that matter contain /../ or similar >> constructs will never match, since they get compared to sanitized paths >> from directory traversal, sanitize those patterns too. > > May also state that the user is now warned if such patterns are encountered. > >> Tested by creating a .pxarexclude file and via the --exclude command >> line option. > > Would not include explicitly that you tested this in the commit message, > it should rather state that this has effect for both cases. Don't get me > wrong, it can make sense to include such information as well, e.g. as > future references for more complex command invocations, just a bit to > much for this trivial test case IMHO. > >> > > your comment from here ... > >> I'm unsure if we should accept those silently, currently I added a >> warning for patterns supplied via the cli option, since that feels most >> susceptible to wrong usage. >> >> It might also make sense to base the patterns for the cli arg on the >> cwd, but that would be a breaking change. > > ... to here should not be part of the commit message (which will be > applied), but rather be additional notes which go below the `---` > separator (where it does not get applied). See marking below. > >> >> Signed-off-by: Manuel Federanko >> Fixes: https://bugzilla.proxmox.com/show_bug.cgi?id=5247 >> --- > > -> additional notes and comments here > >> pbs-client/src/pxar/create.rs | 7 ++++++- >> pbs-client/src/pxar/tools.rs | 32 +++++++++++++++++++++++++++++++ >> proxmox-backup-client/src/main.rs | 16 ++++++++++++++-- >> 3 files changed, 52 insertions(+), 3 deletions(-) >> >> diff --git a/pbs-client/src/pxar/create.rs b/pbs-client/src/pxar/create.rs >> index e42bcc87..1c878cb7 100644 >> --- a/pbs-client/src/pxar/create.rs >> +++ b/pbs-client/src/pxar/create.rs >> @@ -560,7 +560,12 @@ impl Archiver { >> (line, MatchType::Exclude, false) >> }; >> >> - match MatchEntry::parse_pattern(line, PatternFlag::PATH_NAME, mode) { >> + let line_normalized = crate::pxar::tools::normalize_lexically(OsStr::from_bytes(line)); >> + match MatchEntry::parse_pattern( >> + line_normalized.as_path().as_os_str().as_bytes(), >> + PatternFlag::PATH_NAME, >> + mode, >> + ) { >> Ok(pattern) => { >> if anchored { >> self.patterns.push(pattern.add_flags(MatchFlag::ANCHORED)); >> diff --git a/pbs-client/src/pxar/tools.rs b/pbs-client/src/pxar/tools.rs >> index 475c08ad..71a38b29 100644 >> --- a/pbs-client/src/pxar/tools.rs >> +++ b/pbs-client/src/pxar/tools.rs >> @@ -76,6 +76,38 @@ fn assert_single_path_component_do(path: &Path) -> Result<(), Error> { >> Ok(()) >> } >> >> +pub fn normalize_lexically + ?Sized>(path: &S) -> PathBuf { >> + normalize_lexically_do(Path::new(path)) > > comment: `path` could be wrapped here and the function in-lined: > > let path = Path::new(path); > [...] > > >> +} >> +fn normalize_lexically_do(path: &Path) -> PathBuf { >> + // Once std::path::normalize_lexically is stabilized we can switch >> + // to that > > comment: This comment warrants a FIXME: prefix. > >> + use std::path::Component; >> + let has_trailing_slash = path >> + .as_os_str() >> + .as_encoded_bytes() >> + .last() >> + .copied() >> + .is_some_and(|c: u8| c == std::path::MAIN_SEPARATOR_STR.bytes().last().unwrap()); >> + let mut new = PathBuf::new(); >> + let iter = path.components(); >> + for component in iter { >> + match component { >> + Component::RootDir => new.push(Component::RootDir), >> + Component::Prefix(p) => new.push(Component::Prefix(p)), >> + Component::CurDir => continue, >> + Component::ParentDir => { >> + new.pop(); >> + } >> + Component::Normal(n) => new.push(n), >> + }; >> + } >> + if has_trailing_slash { >> + new.push(""); >> + } >> + new >> +} >> + >> #[rustfmt::skip] >> fn symbolic_mode(c: u64, special: bool, special_x: u8, special_no_x: u8) -> [u8; 3] { >> [ >> diff --git a/proxmox-backup-client/src/main.rs b/proxmox-backup-client/src/main.rs >> index 2ada87bd..4ed23d6e 100644 >> --- a/proxmox-backup-client/src/main.rs >> +++ b/proxmox-backup-client/src/main.rs >> @@ -826,9 +826,21 @@ async fn create_backup( >> let entry = entry >> .as_str() >> .ok_or_else(|| format_err!("Invalid pattern string slice"))?; >> + let entry_normalized = pbs_client::pxar::tools::normalize_lexically(entry); >> + if entry_normalized.as_os_str() != entry { >> + log::info!( > > nit: better escalate this to a log::warn! > After all it has proven to behave unexpectedly to some users. > >> + "Sanitized exclude pattern. Exclude patterns are relative to backup root, \ >> + not the current working directory and should not contain '.' or '..' as path \ >> + segments" >> + ); >> + } >> pattern_list.push( >> - MatchEntry::parse_pattern(entry, PatternFlag::PATH_NAME, MatchType::Exclude) >> - .map_err(|err| format_err!("invalid exclude pattern entry: {}", err))?, >> + MatchEntry::parse_pattern( >> + entry_normalized.as_os_str().as_encoded_bytes(), >> + PatternFlag::PATH_NAME, >> + MatchType::Exclude, >> + ) >> + .map_err(|err| format_err!("invalid exclude pattern entry: {}", err))?, >> ); >> } >> >