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* elf: Clean up GLIBC_PRIVATE exports of internal libdl symbolsFlorian Weimer2021-07-079-243/+4
| | | | | | | | They are no longer needed after everything has been moved into libc. The _dl_vsym test has to be removed because the symbol cannot be used outside libc anymore. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* elf: Call free from base namespace on error in dl-libc.c [BZ #27646]Florian Weimer2021-07-061-1/+1
| | | | | | | | | | | | In dlerror_run, free corresponds to the local malloc in the namespace, but GLRO (dl_catch_error) uses the malloc from the base namespace. elf/tst-dlmopen-gethostbyname triggers this mismatch, but it does not crash, presumably because of a fastbin deallocation. Fixes commit c2059edce20c124d1a99f1a94cc52e83b77a917a ("elf: Use _dl_catch_error from base namespace in dl-libc.c [BZ #27646]") and commit b2964eb1d9a6b8ab1250e8a881cf406182da5875 ("dlfcn: Failures after dlmopen should not terminate process [BZ #24772]").
* Linux: Cleanups after librt moveFlorian Weimer2021-06-281-1/+3
| | | | | | | | | | | | librt.so is no longer installed for PTHREAD_IN_LIBC, and tests are not linked against it. $(librt) is introduced globally for shared tests that need to be linked for both PTHREAD_IN_LIBC and !PTHREAD_IN_LIBC. GLIBC_PRIVATE symbols that were needed during the transition are removed again. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* Install shared objects under their ABI namesFlorian Weimer2021-06-281-8/+2
| | | | | | | | | | | | | Previously, the installed objects were named like libc-2.33.so, and the ABI soname libc.so.6 was just a symbolic link. The Makefile targets to install these symbolic links are no longer needed after this, so they are removed with this commit. The more general $(make-link) command (which invokes scripts/rellns-sh) is retained because other symbolic links are still needed. Reviewed-by: Carlos O'Donell <carlos@redhat.com> Tested-by: Carlos O'Donell <carlos@rehdat.com>
* elf: Generalize name-based DSO recognition in ldconfigFlorian Weimer2021-06-284-4/+72
| | | | | | | | | This introduces <dl-is_dso.h> and the _dl_is_dso function. A test ensures that the official names of libc.so, ld.so, and their versioned names are recognized. Reviewed-by: Carlos O'Donell <carlos@redhat.com> Tested-by: Carlos O'Donell <carlos@redhat.com>
* elf: Disable most of TLS modid gaps processing [BZ #27135]Florian Weimer2021-06-253-6/+15
| | | | | | | | | | | | | Revert "elf: Fix DTV gap reuse logic [BZ #27135]" This reverts commit 572bd547d57a39b6cf0ea072545dc4048921f4c3. It turns out that the _dl_next_tls_modid in _dl_map_object_from_fd keeps returning the same modid over and over again if there is a gap and more than TLS-using module is loaded in one dlopen call. This corrupts TLS data structures. The bug is still present after a revert, but empirically it is much more difficult to trigger (because it involves a dlopen failure).
* elf: Fix glibc-hwcaps priorities with cache flags mismatches [BZ #27046]Florian Weimer2021-06-251-64/+60
| | | | | | | | | | | | | | | | | | | | If lib->flags (in the cache) did not match GLRO (dl_correct_cache_id), searching for further glibc-hwcaps entries did not happen, and it was possible that the best glibc-hwcaps was not found. By accident, this causes a test failure for elf/tst-glibc-hwcaps-prepend-cache on armv7l. This commit changes the cache lookup logic to continue searching if (a) no match has been found, (b) a named glibc-hwcaps match has been found(), or (c) non-glibc-hwcaps match has been found and the entry flags and cache default flags do not match. _DL_CACHE_DEFAULT_ID is used instead of GLRO (dl_correct_cache_id) because the latter is only written once on i386 if loading of libc.so.5 libraries is selected, so GLRO (dl_correct_cache_id) should probably removed in a future change. Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
* Use 64 bit time_t stat internallyAdhemerval Zanella2021-06-223-8/+8
| | | | | | | | | | For the legacy ABI with supports 32-bit time_t it calls the 64-bit time directly, since the LFS symbols calls the 64-bit time_t ones internally. Checked on i686-linux-gnu and x86_64-linux-gnu. Reviewed-by: Lukasz Majewski <lukma@denx.de>
* elf: Use _dl_catch_error from base namespace in dl-libc.c [BZ #27646]Florian Weimer2021-06-174-3/+66
| | | | | | | | | | | dlerrror_run in elf/dl-libc.c needs to call GLRO (dl_catch_error) from the base namespace, just like the exported dlerror implementation. Fixes commit b2964eb1d9a6b8ab1250e8a881cf406182da5875 ("dlfcn: Failures after dlmopen should not terminate process [BZ #24772]"). Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
* Remove stale references to libdl.aFlorian Weimer2021-06-091-6/+1
| | | | | | | | Since commit 0c1c3a771eceec46e66ce1183cf988e2303bd373 ("dlfcn: Move dlopen into libc") libdl.a is empty, so linking against it is no longer necessary. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* Fix elf/tst-tls9-static after libdl cleanups.Stefan Liebler2021-06-091-2/+0
| | | | | | | | | | | | The testcase elf/tst-tls9-static sometimes fails with: cannot open 'tst-tlsmod5.so': tst-tlsmod5.so: cannot open shared object file: No such file or directory cannot open 'tst-tlsmod6.so': tst-tlsmod6.so: cannot open shared object file: No such file or directory After recent commit 6f1c701026287f6928d3bdd1aea7359308635abe "dlfcn: Cleanups after -ldl is no longer required" the libdl variable is not set anymore and thus the dependencies were missing.
* dlfcn: Rework static dlopen hooksFlorian Weimer2021-06-033-68/+24
| | | | | | | | | | | | | | Consolidate all hooks structures into a single one. There are no static dlopen ABI concerns because glibc 2.34 already comes with substantial ABI-incompatible changes in this area. (Static dlopen requires the exact same dynamic glibc version that was used for static linking.) The new approach uses a pointer to the hooks structure into _rtld_global_ro and initalizes it in __rtld_static_init. This avoids a back-and-forth with various callback functions. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* dlfcn: Cleanups after -ldl is no longer requiredFlorian Weimer2021-06-031-143/+29
| | | | | | | | | | | | This commit removes the ELF constructor and internal variables from dlfcn/dlfcn.c. The file now serves the same purpose as nptl/libpthread-compat.c, so it is renamed to dlfcn/libdl-compat.c. The use of libdl-shared-only-routines ensures that libdl.a is empty. This commit adjusts the test suite not to use $(libdl). The libdl.so symbolic link is no longer installed. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* dlfcn: Move dlvsym into libcFlorian Weimer2021-06-031-1/+1
| | | | | | The symbol was moved using scripts/move-symbol-to-libc.py. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* dlfcn: Move dlsym into libcFlorian Weimer2021-06-032-1/+1
| | | | | | | | | | The symbol was moved using scripts/move-symbol-to-libc.py. In elf/Makefile, remove the $(libdl) dependency from testobj1.so because it the unused libdl DSO now causes elf/tst-unused-deps to fail. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* elf: Use custom NODELETE DSO for tst-dlopenfail, tst-dlopenfail-2Florian Weimer2021-05-215-36/+61
| | | | | | | Once libpthread is empty and no longer marked NODELETE, it no longer can be used for testing. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* nptl: Eliminate the __static_tls_size, __static_tls_align_m1 variablesFlorian Weimer2021-05-211-2/+3
| | | | | | | | | | | | | | | | | | | Use the __nptl_tls_static_size_for_stack inline function instead, and the GLRO (dl_tls_static_align) value directly. The computation of GLRO (dl_tls_static_align) in _dl_determine_tlsoffset ensures that the alignment is at least TLS_TCB_ALIGN, which at least STACK_ALIGN (see allocate_stack). Therefore, the additional rounding-up step is removed. ALso move the initialization of the default stack size from __pthread_initialize_minimal_internal to __pthread_early_init. This introduces an extra system call during single-threaded startup, but this simplifies the initialization sequence. No locking is needed around the writes to __default_pthread_attr because the process is single-threaded at this point. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* elf: Initialize GLRO (dl_minsigstacksize) after static dlopenFlorian Weimer2021-05-201-0/+3
| | | | | | | This is another field of _rtld_global_ro that benefits from initialization in __rtld_static_init. Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
* elf: Add hook for checking HWCAP bits after auxiliary vector parsingFlorian Weimer2021-05-191-0/+3
| | | | Reviewed-by: Stefan Liebler <stli@linux.ibm.com>
* ldconfig: Avoid boolean coercion of opt_chrootSiddhesh Poyarekar2021-05-181-17/+17
| | | | Generated code is unchanged.
* ldconfig: Fix memory leaksSiddhesh Poyarekar2021-05-181-6/+14
| | | | | | | Coverity discovered that paths allocated by chroot_canon are not freed in a couple of routines in ldconfig. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* elf/cache.c: Fix resource leaks identified by static analyzersSiddhesh Poyarekar2021-05-181-4/+12
| | | | | | | | | | A coverity run identified a number of resource leaks in cache.c. There are a couple of simple memory leaks where a local allocation is not freed before function return. Then there is a mmap leak and a file descriptor leak where a map is not unmapped in the error case and a file descriptor remains open respectively. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* elf: Move static TLS size and alignment into _rtld_global_roFlorian Weimer2021-05-173-14/+20
| | | | | | | This helps to clarify that the caching of these fields in libpthread (in __static_tls_size, __static_tls_align_m1) is unnecessary. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* elf: Remove DL_STATIC_INITFlorian Weimer2021-05-171-4/+0
| | | | | | All users have been converted to the __rtld_static_init mechanism. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* elf: Partially initialize ld.so after static dlopen (bug 20802)Florian Weimer2021-05-175-5/+174
| | | | | | | | | | | | | | After static dlopen, a copy of ld.so is loaded into the inner namespace, but that copy is not initialized at all. Some architectures run into serious problems as result, which is why the _dl_var_init mechanism was invented. With libpthread moving into libc and parts into ld.so, more architectures impacted, so it makes sense to switch to a generic mechanism which performs the partial initialization. As a result, getauxval now works after static dlopen (bug 20802). Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* Remove all usage of @BASH@ or ${BASH} in installed files, and hardcode ↵Romain GEISSLER2021-05-123-5/+3
| | | | | | | | | | | | | | | | | | | /bin/bash instead (FYI, this is a repost of https://sourceware.org/pipermail/libc-alpha/2019-July/105035.html now that FSF papers have been signed and confirmed on FSF side). This trivial patch attemps to fix BZ 24106. Basically the bash locally used when building glibc on the host shall not leak on the installed glibc, as the system where it is installed might be different and use another bash location. So I have looked for all occurences of @BASH@ or $(BASH) in installed files, and replaced it by /bin/bash. This was suggested by Florian Weimer in the bug report. Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
* elf: Fix DTV gap reuse logic [BZ #27135]Szabolcs Nagy2021-05-113-15/+6
| | | | | | | | | | | | | | | | | | | | | | | For some reason only dlopen failure caused dtv gaps to be reused. It is possible that the intent was to never reuse modids for a different module, but after dlopen failure all gaps are reused not just the ones caused by the unfinished dlopened. So the code has to handle reused modids already which seems to work, however the data races at thread creation and tls access (see bug 19329 and bug 27111) may be more severe if slots are reused so this is scheduled after those fixes. I think fixing the races are not simpler if reuse is disallowed and reuse has other benefits, so set GL(dl_tls_dtv_gaps) whenever entries are removed from the middle of the slotinfo list. The value does not have to be correct: incorrect true value causes the next modid query to do a slotinfo walk, incorrect false will leave gaps and new entries are added at the end. Fixes bug 27135. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* elf: Add test case for [BZ #19329]Szabolcs Nagy2021-05-113-2/+76
| | | | | | | | | | | | | Test concurrent dlopen and pthread_create when the loaded modules have TLS. This triggers dl-tls assertion failures more reliably than the nptl/tst-stack4 test. The dlopened module has 100 DT_NEEDED dependencies with TLS, they were reused from an existing TLS test. The number of created threads during dlopen depends on filesystem speed and hardware, but at most 3 threads are alive at a time to limit resource usage. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* elf: Use relaxed atomics for racy accesses [BZ #19329]Szabolcs Nagy2021-05-113-16/+40
| | | | | | | | | | | | | | | | | | This is a follow up patch to the fix for bug 19329. This adds relaxed MO atomics to accesses that were previously data races but are now race conditions, and where relaxed MO is sufficient. The race conditions all follow the pattern that the write is behind the dlopen lock, but a read can happen concurrently (e.g. during tls access) without holding the lock. For slotinfo entries the read value only matters if it reads from a synchronized write in dlopen or dlclose, otherwise the related dtv entry is not valid to access so it is fine to leave it in an inconsistent state. The same applies for GL(dl_tls_max_dtv_idx) and GL(dl_tls_generation), but there the algorithm relies on the fact that the read of the last synchronized write is an increasing value. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* elf: Fix data races in pthread_create and TLS access [BZ #19329]Szabolcs Nagy2021-05-111-16/+47
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | DTV setup at thread creation (_dl_allocate_tls_init) is changed to take the dlopen lock, GL(dl_load_lock). Avoiding data races here without locks would require design changes: the map that is accessed for static TLS initialization here may be concurrently freed by dlclose. That use after free may be solved by only locking around static TLS setup or by ensuring dlclose does not free modules with static TLS, however currently every link map with TLS has to be accessed at least to see if it needs static TLS. And even if that's solved, still a lot of atomics would be needed to synchronize DTV related globals without a lock. So fix both bug 19329 and bug 27111 with a lock that prevents DTV setup running concurrently with dlopen or dlclose. _dl_update_slotinfo at TLS access still does not use any locks so CONCURRENCY NOTES are added to explain the synchronization. The early exit from the slotinfo walk when max_modid is reached is not strictly necessary, but does not hurt either. An incorrect acquire load was removed from _dl_resize_dtv: it did not synchronize with any release store or fence and synchronization is now handled separately at thread creation and TLS access time. There are still a number of racy read accesses to globals that will be changed to relaxed MO atomics in a followup patch. This should not introduce regressions compared to existing behaviour and avoid cluttering the main part of the fix. Not all TLS access related data races got fixed here: there are additional races at lazy tlsdesc relocations see bug 27137. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* _dl_exception_create_format: Add missing va_endSiddhesh Poyarekar2021-05-111-0/+1
| | | | Coverity discovered a missing va_end.
* nptl: Move changing of stack permissions into ld.soFlorian Weimer2021-05-103-6/+10
| | | | | | | | | All the stack lists are now in _rtld_global, so it is possible to change stack permissions directly from there, instead of calling into libpthread to do the change. Tested-by: Carlos O'Donell <carlos@redhat.com> Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* nptl: Move more stack management variables into _rtld_globalFlorian Weimer2021-05-101-0/+3
| | | | | | | | | | | | Permissions of the cached stacks may have to be updated if an object is loaded that requires executable stacks, so the dynamic loader needs to know about these cached stacks. The move of in_flight_stack and stack_cache_actsize is a requirement for merging __reclaim_stacks into the fork implementation in libc. Tested-by: Carlos O'Donell <carlos@redhat.com> Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* elf: Introduce __tls_pre_init_tpFlorian Weimer2021-05-103-38/+31
| | | | | | | | | | | This is an early variant of __tls_init_tp, primarily for initializing thread-related elements of _rtld_global/GL. Some existing initialization code not needed for NPTL is moved into the generic version of this function. Tested-by: Carlos O'Donell <carlos@redhat.com> Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* elf, nptl: Resolve recursive lock implementation earlyFlorian Weimer2021-05-103-1/+39
| | | | | | | | | | | If libpthread is included in libc, it is not necessary to delay initialization of the lock/unlock function pointers until libpthread is loaded. This eliminates two unprotected function pointers from _rtld_global and removes some initialization code from libpthread. Tested-by: Carlos O'Donell <carlos@redhat.com> Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* nptl: Consolidate async cancel enable/disable implementation in libcFlorian Weimer2021-05-051-2/+4
| | | | | | | | | | | | | | Previously, the source file nptl/cancellation.c was compiled multiple times, for libc, libpthread, librt. This commit switches to a single implementation, with new __pthread_enable_asynccancel@@GLIBC_PRIVATE, __pthread_disable_asynccancel@@GLIBC_PRIVATE exports. The almost-unused CANCEL_ASYNC and CANCEL_RESET macros are replaced by LIBC_CANCEL_ASYNC and LIBC_CANCEL_ASYNC macros. They call the __pthread_* functions unconditionally now. The macros are still needed because shared code uses them; Hurd has different definitions. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* elf, nptl: Initialize static TLS directly in ld.soFlorian Weimer2021-05-055-5/+46
| | | | | | | | | | The stack list is available in ld.so since commit 1daccf403b1bd86370eb94edca794dc106d02039 ("nptl: Move stack list variables into _rtld_global"), so it's possible to walk the stack list directly in ld.so and perform the initialization there. This eliminates an unprotected function pointer from _rtld_global and reduces the libpthread initialization code.
* pthread: Introduce __pthread_early_initFlorian Weimer2021-04-211-0/+3
| | | | | | | This function is called from __libc_early_init to initialize the pthread subsystem. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* elf: Introduce __tls_init_tp for second-phase TCB initializationFlorian Weimer2021-04-213-13/+27
| | | | | | | | | | TLS_INIT_TP is processor-specific, so it is not a good place to put thread library initialization code (it would have to be repeated for all CPUs). Introduce __tls_init_tp as a separate function, to be called immediately after TLS_INIT_TP. Move the existing stack list setup code for NPTL to this function. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* dlfcn: dlerror needs to call free from the base namespace [BZ #24773]Florian Weimer2021-04-214-11/+52
| | | | | | | | | | | | Calling free directly may end up freeing a pointer allocated by the dynamic loader using malloc from libc.so in the base namespace using the allocator from libc.so in a secondary namespace, which results in crashes. This commit redirects the free call through GLRO and the dynamic linker, to reach the correct namespace. It also cleans up the dlerror handling along the way, so that pthread_setspecific is no longer needed (which avoids triggering bug 24774).
* dlfcn: Failures after dlmopen should not terminate process [BZ #24772]Florian Weimer2021-04-215-2/+97
| | | | | | | | | | | | | | | | | | | Commit 9e78f6f6e7134a5f299cc8de77370218f8019237 ("Implement _dl_catch_error, _dl_signal_error in libc.so [BZ #16628]") has the side effect that distinct namespaces, as created by dlmopen, now have separate implementations of the rtld exception mechanism. This means that the call to _dl_catch_error from libdl in a secondary namespace does not actually install an exception handler because the thread-local variable catch_hook in the libc.so copy in the secondary namespace is distinct from that of the base namepace. As a result, a dlsym/dlopen/... failure in a secondary namespace terminates the process with a dynamic linker error because it looks to the exception handler mechanism as if no handler has been installed. This commit restores GLRO (dl_catch_error) and uses it to set the handler in the base namespace. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* nptl: Move __pthread_unwind_next into libcFlorian Weimer2021-04-211-0/+2
| | | | | | | | | | | | | | | | | | | It's necessary to stub out __libc_disable_asynccancel and __libc_enable_asynccancel via rtld-stubbed-symbols because the new direct references to the unwinder result in symbol conflicts when the rtld exception handling from libc is linked in during the construction of librtld.map. unwind-forcedunwind.c is merged into unwind-resume.c. libc now needs the functions that were previously only used in libpthread. The GLIBC_PRIVATE exports of __libc_longjmp and __libc_siglongjmp are no longer needed, so switch them to hidden symbols. The symbol __pthread_unwind_next has been moved using scripts/move-symbol-to-libc.py. Reviewed-by: Adhemerva Zanella <adhemerval.zanella@linaro.org>
* elf: Remove lazy tlsdesc relocation related codeSzabolcs Nagy2021-04-211-47/+6
| | | | | | | | | | | Remove generic tlsdesc code related to lazy tlsdesc processing since lazy tlsdesc relocation is no longer supported. This includes removing GL(dl_load_lock) from _dl_make_tlsdesc_dynamic which is only called at load time when that lock is already held. Added a documentation comment too. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* elf: Fix missing include in test case [BZ #27136]Szabolcs Nagy2021-04-151-0/+1
| | | | | | | Broken test was introduced in commit 8f85075a2e9c26ff7486d4bbaf358999807d215c elf: Add a DTV setup test [BZ #27136]
* elf: Refactor _dl_update_slotinfo to avoid use after freeSzabolcs Nagy2021-04-151-16/+5
| | | | | | | | | | | | map is not valid to access here because it can be freed by a concurrent dlclose: during tls access (via __tls_get_addr) _dl_update_slotinfo is called without holding dlopen locks. So don't check the modid of map. The map == 0 and map != 0 code paths can be shared (avoiding the dtv resize in case of map == 0 is just an optimization: larger dtv than necessary would be fine too). Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* elf: Fix comments and logic in _dl_add_to_slotinfoSzabolcs Nagy2021-04-151-10/+1
| | | | | | | | | | | | | | | Since commit a509eb117fac1d764b15eba64993f4bdb63d7f3c Avoid late dlopen failure due to scope, TLS slotinfo updates [BZ #25112] the generation counter update is not needed in the failure path. That commit ensures allocation in _dl_add_to_slotinfo happens before the demarcation point in dlopen (it is called twice, first time is for allocation only where dlopen can still be reverted on failure, then second time actual dtv updates are done which then cannot fail). Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* elf: Add a DTV setup test [BZ #27136]Szabolcs Nagy2021-04-153-1/+109
| | | | | | | | | | | The test dlopens a large number of modules with TLS, they are reused from an existing test. The test relies on the reuse of slotinfo entries after dlclose, without bug 27135 fixed this needs a failing dlopen. With a slotinfo list that has non-monotone increasing generation counters, bug 27136 can trigger. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* elf: Fix a DTV setup issue [BZ #27136]Szabolcs Nagy2021-04-151-1/+1
| | | | | | | | | | | The max modid is a valid index in the dtv, it should not be skipped. The bug is observable if the last module has modid == 64 and its generation is same or less than the max generation of the previous modules. Then dtv[0].counter implies dtv[64] is initialized but it isn't. Fixes bug 27136. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* Fix SXID_ERASE behavior in setuid programs (BZ #27471)Siddhesh Poyarekar2021-04-122-30/+52
| | | | | | | | | | | | | | | | | | | | | | | | | When parse_tunables tries to erase a tunable marked as SXID_ERASE for setuid programs, it ends up setting the envvar string iterator incorrectly, because of which it may parse the next tunable incorrectly. Given that currently the implementation allows malformed and unrecognized tunables pass through, it may even allow SXID_ERASE tunables to go through. This change revamps the SXID_ERASE implementation so that: - Only valid tunables are written back to the tunestr string, because of which children of SXID programs will only inherit a clean list of identified tunables that are not SXID_ERASE. - Unrecognized tunables get scrubbed off from the environment and subsequently from the child environment. - This has the side-effect that a tunable that is not identified by the setxid binary, will not be passed on to a non-setxid child even if the child could have identified that tunable. This may break applications that expect this behaviour but expecting such tunables to cross the SXID boundary is wrong. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* Enhance setuid-tunables testSiddhesh Poyarekar2021-04-122-23/+69
| | | | | | | | | | Instead of passing GLIBC_TUNABLES via the environment, pass the environment variable from parent to child. This allows us to test multiple variables to ensure better coverage. The test list currently only includes the case that's already being tested. More tests will be added later. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
generated by cgit-pink 1.4.1 (git 2.36.1) at 2024-11-23 18:54:32 +0000