| Message ID | 87edhlwq6y.fsf@oldenburg.str.redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | ldconfig: Actually ignore dpkg-related temporarily files | expand |
Hi! On Mon, 2023-10-23 at 13:09:25 +0200, Florian Weimer wrote: > These files actually end in .dpkg-new and .dpkg-tmp, not .tmp > as I mistakenly assumed. > > Fixes commit 2aa0974d2573441bffd59 ("elf: ldconfig should skip > temporary files created by package managers"). > > --- > elf/ldconfig.c | 17 ++++++++++++++--- > 1 file changed, 14 insertions(+), 3 deletions(-) > > diff --git a/elf/ldconfig.c b/elf/ldconfig.c > index 02387a169c..4abde26e60 100644 > --- a/elf/ldconfig.c > +++ b/elf/ldconfig.c > @@ -661,6 +661,17 @@ struct dlib_entry > struct dlib_entry *next; > }; > > +/* Return true if the N bytes at NAME end with with the characters in > + the string SUFFIX. (NAME[N + 1] does not have to be a null byte.) > + Expected to be called with a string literal for SUFFIX. */ > +static inline bool > +endswithn (const char *name, size_t n, const char *suffix) > +{ > + return (n >= strlen (suffix) > + && memcmp (name + n - strlen (suffix), suffix, > + strlen (suffix)) == 0); > +} > + > /* Skip some temporary DSO files. These files may be partially written > and lead to ldconfig crashes when examined. */ > static bool > @@ -670,8 +681,7 @@ skip_dso_based_on_name (const char *name, size_t len) > names like these are never really DSOs we want to look at. */ > if (len >= sizeof (".#prelink#") - 1) > { > - if (strcmp (name + len - sizeof (".#prelink#") + 1, > - ".#prelink#") == 0) > + if (endswithn (name, len, ".#prelink#")) > return true; > if (len >= sizeof (".#prelink#.XXXXXX") - 1 > && memcmp (name + len - sizeof (".#prelink#.XXXXXX") > @@ -682,7 +692,8 @@ skip_dso_based_on_name (const char *name, size_t len) > if (memchr (name, len, ';') != NULL) > return true; > /* Skip temporary files created by dpkg. */ > - if (len > 4 && memcmp (name + len - 4, ".tmp", 4) == 0) > + if (endswithn (name, len, ".dpkg-new") > + || endswithn (name, len, ".dpkg-tmp")) > return true; > return false; > } > > base-commit: 2aa0974d2573441bffd596b07bff8698b1f2f18c Thanks, LGTM! I've tentatively queued the attached patch (will review it further for correctness later today) trying to document these files in dpkg(1), as I noticed this does not seem to be documented anywhere (except in code comments), in the hopes it will help the next person. :) Thanks, Guillem
Hi! On Tue, 2023-10-24 at 13:45:22 +0200, Guillem Jover wrote: > On Mon, 2023-10-23 at 13:09:25 +0200, Florian Weimer wrote: > > These files actually end in .dpkg-new and .dpkg-tmp, not .tmp > > as I mistakenly assumed. > > > > Fixes commit 2aa0974d2573441bffd59 ("elf: ldconfig should skip > > temporary files created by package managers"). > Thanks, LGTM! Ah, just noticed now that the NEWS entry for this change did not get updated. It reads: ,--- |* The ldconfig program now skips file names containing ';' or ending in | ".tmp", to avoid examining temporary files created by the RPM and dpkg | package managers. `--- Thanks, Guillem
diff --git a/elf/ldconfig.c b/elf/ldconfig.c index 02387a169c..4abde26e60 100644 --- a/elf/ldconfig.c +++ b/elf/ldconfig.c @@ -661,6 +661,17 @@ struct dlib_entry struct dlib_entry *next; }; +/* Return true if the N bytes at NAME end with with the characters in + the string SUFFIX. (NAME[N + 1] does not have to be a null byte.) + Expected to be called with a string literal for SUFFIX. */ +static inline bool +endswithn (const char *name, size_t n, const char *suffix) +{ + return (n >= strlen (suffix) + && memcmp (name + n - strlen (suffix), suffix, + strlen (suffix)) == 0); +} + /* Skip some temporary DSO files. These files may be partially written and lead to ldconfig crashes when examined. */ static bool @@ -670,8 +681,7 @@ skip_dso_based_on_name (const char *name, size_t len) names like these are never really DSOs we want to look at. */ if (len >= sizeof (".#prelink#") - 1) { - if (strcmp (name + len - sizeof (".#prelink#") + 1, - ".#prelink#") == 0) + if (endswithn (name, len, ".#prelink#")) return true; if (len >= sizeof (".#prelink#.XXXXXX") - 1 && memcmp (name + len - sizeof (".#prelink#.XXXXXX") @@ -682,7 +692,8 @@ skip_dso_based_on_name (const char *name, size_t len) if (memchr (name, len, ';') != NULL) return true; /* Skip temporary files created by dpkg. */ - if (len > 4 && memcmp (name + len - 4, ".tmp", 4) == 0) + if (endswithn (name, len, ".dpkg-new") + || endswithn (name, len, ".dpkg-tmp")) return true; return false; }
These files actually end in .dpkg-new and .dpkg-tmp, not .tmp as I mistakenly assumed. Fixes commit 2aa0974d2573441bffd59 ("elf: ldconfig should skip temporary files created by package managers"). --- elf/ldconfig.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) base-commit: 2aa0974d2573441bffd596b07bff8698b1f2f18c