user/sven/linux.git, branch v4.19.133

Linux 4.19.133

2020-07-16T06:17:28Z

s390/mm: fix huge pte soft dirty copying

2020-07-16T06:17:28Z

commit 528a9539348a0234375dfaa1ca5dbbb2f8f8e8d2 upstream. If the pmd is soft dirty we must mark the pte as soft dirty (and not dirty). This fixes some cases for guest migration with huge page backings. Cc: # 4.8 Fixes: bc29b7ac1d9f ("s390/mm: clean up pte/pmd encoding") Reviewed-by: Christian Borntraeger Reviewed-by: Gerald Schaefer Signed-off-by: Janosch Frank Signed-off-by: Heiko Carstens Signed-off-by: Greg Kroah-Hartman

ARC: elf: use right ELF_ARCH

2020-07-16T06:17:27Z

commit b7faf971081a4e56147f082234bfff55135305cb upstream. Cc: Signed-off-by: Vineet Gupta Signed-off-by: Greg Kroah-Hartman

ARC: entry: fix potential EFA clobber when TIF_SYSCALL_TRACE

2020-07-16T06:17:27Z

commit 00fdec98d9881bf5173af09aebd353ab3b9ac729 upstream. Trap handler for syscall tracing reads EFA (Exception Fault Address), in case strace wants PC of trap instruction (EFA is not part of pt_regs as of current code). However this EFA read is racy as it happens after dropping to pure kernel mode (re-enabling interrupts). A taken interrupt could context-switch, trigger a different task's trap, clobbering EFA for this execution context. Fix this by reading EFA early, before re-enabling interrupts. A slight side benefit is de-duplication of FAKE_RET_FROM_EXCPN in trap handler. The trap handler is common to both ARCompact and ARCv2 builds too. This just came out of code rework/review and no real problem was reported but is clearly a potential problem specially for strace. Cc: Signed-off-by: Vineet Gupta Signed-off-by: Greg Kroah-Hartman

dm: use noio when sending kobject event

2020-07-16T06:17:27Z

commit 6958c1c640af8c3f40fa8a2eee3b5b905d95b677 upstream. kobject_uevent may allocate memory and it may be called while there are dm devices suspended. The allocation may recurse into a suspended device, causing a deadlock. We must set the noio flag when sending a uevent. The observed deadlock was reported here: https://www.redhat.com/archives/dm-devel/2020-March/msg00025.html Reported-by: Khazhismel Kumykov Reported-by: Tahsin Erdogan Reported-by: Gabriel Krisman Bertazi Signed-off-by: Mikulas Patocka Cc: stable@vger.kernel.org Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman

drm/radeon: fix double free

2020-07-16T06:17:27Z

commit 41855a898650803e24b284173354cc3e44d07725 upstream. clang static analysis flags this error drivers/gpu/drm/radeon/ci_dpm.c:5652:9: warning: Use of memory after it is freed [unix.Malloc] kfree(rdev->pm.dpm.ps[i].ps_priv); ^~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/gpu/drm/radeon/ci_dpm.c:5654:2: warning: Attempt to free released memory [unix.Malloc] kfree(rdev->pm.dpm.ps); ^~~~~~~~~~~~~~~~~~~~~~ problem is reported in ci_dpm_fini, with these code blocks. for (i = 0; i < rdev->pm.dpm.num_ps; i++) { kfree(rdev->pm.dpm.ps[i].ps_priv); } kfree(rdev->pm.dpm.ps); The first free happens in ci_parse_power_table where it cleans up locally on a failure. ci_dpm_fini also does a cleanup. ret = ci_parse_power_table(rdev); if (ret) { ci_dpm_fini(rdev); return ret; } So remove the cleanup in ci_parse_power_table and move the num_ps calculation to inside the loop so ci_dpm_fini will know how many array elements to free. Fixes: cc8dbbb4f62a ("drm/radeon: add dpm support for CI dGPUs (v2)") Signed-off-by: Tom Rix Signed-off-by: Alex Deucher Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman

btrfs: fix fatal extent_buffer readahead vs releasepage race

2020-07-16T06:17:27Z

commit 6bf9cd2eed9aee6d742bb9296c994a91f5316949 upstream. Under somewhat convoluted conditions, it is possible to attempt to release an extent_buffer that is under io, which triggers a BUG_ON in btrfs_release_extent_buffer_pages. This relies on a few different factors. First, extent_buffer reads done as readahead for searching use WAIT_NONE, so they free the local extent buffer reference while the io is outstanding. However, they should still be protected by TREE_REF. However, if the system is doing signficant reclaim, and simultaneously heavily accessing the extent_buffers, it is possible for releasepage to race with two concurrent readahead attempts in a way that leaves TREE_REF unset when the readahead extent buffer is released. Essentially, if two tasks race to allocate a new extent_buffer, but the winner who attempts the first io is rebuffed by a page being locked (likely by the reclaim itself) then the loser will still go ahead with issuing the readahead. The loser's call to find_extent_buffer must also race with the reclaim task reading the extent_buffer's refcount as 1 in a way that allows the reclaim to re-clear the TREE_REF checked by find_extent_buffer. The following represents an example execution demonstrating the race: CPU0 CPU1 CPU2 reada_for_search reada_for_search readahead_tree_block readahead_tree_block find_create_tree_block find_create_tree_block alloc_extent_buffer alloc_extent_buffer find_extent_buffer // not found allocates eb lock pages associate pages to eb insert eb into radix tree set TREE_REF, refs == 2 unlock pages read_extent_buffer_pages // WAIT_NONE not uptodate (brand new eb) lock_page if !trylock_page goto unlock_exit // not an error free_extent_buffer release_extent_buffer atomic_dec_and_test refs to 1 find_extent_buffer // found try_release_extent_buffer take refs_lock reads refs == 1; no io atomic_inc_not_zero refs to 2 mark_buffer_accessed check_buffer_tree_ref // not STALE, won't take refs_lock refs == 2; TREE_REF set // no action read_extent_buffer_pages // WAIT_NONE clear TREE_REF release_extent_buffer atomic_dec_and_test refs to 1 unlock_page still not uptodate (CPU1 read failed on trylock_page) locks pages set io_pages > 0 submit io return free_extent_buffer release_extent_buffer dec refs to 0 delete from radix tree btrfs_release_extent_buffer_pages BUG_ON(io_pages > 0)!!! We observe this at a very low rate in production and were also able to reproduce it in a test environment by introducing some spurious delays and by introducing probabilistic trylock_page failures. To fix it, we apply check_tree_ref at a point where it could not possibly be unset by a competing task: after io_pages has been incremented. All the codepaths that clear TREE_REF check for io, so they would not be able to clear it after this point until the io is done. Stack trace, for reference: [1417839.424739] ------------[ cut here ]------------ [1417839.435328] kernel BUG at fs/btrfs/extent_io.c:4841! [1417839.447024] invalid opcode: 0000 [#1] SMP [1417839.502972] RIP: 0010:btrfs_release_extent_buffer_pages+0x20/0x1f0 [1417839.517008] Code: ed e9 ... [1417839.558895] RSP: 0018:ffffc90020bcf798 EFLAGS: 00010202 [1417839.570816] RAX: 0000000000000002 RBX: ffff888102d6def0 RCX: 0000000000000028 [1417839.586962] RDX: 0000000000000002 RSI: ffff8887f0296482 RDI: ffff888102d6def0 [1417839.603108] RBP: ffff88885664a000 R08: 0000000000000046 R09: 0000000000000238 [1417839.619255] R10: 0000000000000028 R11: ffff88885664af68 R12: 0000000000000000 [1417839.635402] R13: 0000000000000000 R14: ffff88875f573ad0 R15: ffff888797aafd90 [1417839.651549] FS: 00007f5a844fa700(0000) GS:ffff88885f680000(0000) knlGS:0000000000000000 [1417839.669810] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [1417839.682887] CR2: 00007f7884541fe0 CR3: 000000049f609002 CR4: 00000000003606e0 [1417839.699037] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [1417839.715187] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [1417839.731320] Call Trace: [1417839.737103] release_extent_buffer+0x39/0x90 [1417839.746913] read_block_for_search.isra.38+0x2a3/0x370 [1417839.758645] btrfs_search_slot+0x260/0x9b0 [1417839.768054] btrfs_lookup_file_extent+0x4a/0x70 [1417839.778427] btrfs_get_extent+0x15f/0x830 [1417839.787665] ? submit_extent_page+0xc4/0x1c0 [1417839.797474] ? __do_readpage+0x299/0x7a0 [1417839.806515] __do_readpage+0x33b/0x7a0 [1417839.815171] ? btrfs_releasepage+0x70/0x70 [1417839.824597] extent_readpages+0x28f/0x400 [1417839.833836] read_pages+0x6a/0x1c0 [1417839.841729] ? startup_64+0x2/0x30 [1417839.849624] __do_page_cache_readahead+0x13c/0x1a0 [1417839.860590] filemap_fault+0x6c7/0x990 [1417839.869252] ? xas_load+0x8/0x80 [1417839.876756] ? xas_find+0x150/0x190 [1417839.884839] ? filemap_map_pages+0x295/0x3b0 [1417839.894652] __do_fault+0x32/0x110 [1417839.902540] __handle_mm_fault+0xacd/0x1000 [1417839.912156] handle_mm_fault+0xaa/0x1c0 [1417839.921004] __do_page_fault+0x242/0x4b0 [1417839.930044] ? page_fault+0x8/0x30 [1417839.937933] page_fault+0x1e/0x30 [1417839.945631] RIP: 0033:0x33c4bae [1417839.952927] Code: Bad RIP value. [1417839.960411] RSP: 002b:00007f5a844f7350 EFLAGS: 00010206 [1417839.972331] RAX: 000000000000006e RBX: 1614b3ff6a50398a RCX: 0000000000000000 [1417839.988477] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000002 [1417840.004626] RBP: 00007f5a844f7420 R08: 000000000000006e R09: 00007f5a94aeccb8 [1417840.020784] R10: 00007f5a844f7350 R11: 0000000000000000 R12: 00007f5a94aecc79 [1417840.036932] R13: 00007f5a94aecc78 R14: 00007f5a94aecc90 R15: 00007f5a94aecc40 CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Filipe Manana Signed-off-by: Boris Burkov Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman

Revert "ath9k: Fix general protection fault in ath9k_hif_usb_rx_cb"

2020-07-16T06:17:27Z

This reverts commit bdf4d37b03dc410b91f318c8e097a41e732d1038 which is commit 2bbcaaee1fcbd83272e29f31e2bb7e70d8c49e05 upstream. It is being reverted upstream, just hasn't made it there yet and is causing lots of problems. Reported-by: Hans de Goede Cc: Qiujun Huang Cc: Kalle Valo Signed-off-by: Greg Kroah-Hartman

bpf: Check correct cred for CAP_SYSLOG in bpf_dump_raw_ok()

2020-07-16T06:17:27Z

commit 63960260457a02af2a6cb35d75e6bdb17299c882 upstream. When evaluating access control over kallsyms visibility, credentials at open() time need to be used, not the "current" creds (though in BPF's case, this has likely always been the same). Plumb access to associated file->f_cred down through bpf_dump_raw_ok() and its callers now that kallsysm_show_value() has been refactored to take struct cred. Cc: Alexei Starovoitov Cc: Daniel Borkmann Cc: bpf@vger.kernel.org Cc: stable@vger.kernel.org Fixes: 7105e828c087 ("bpf: allow for correlation of maps and helpers in dump") Signed-off-by: Kees Cook Signed-off-by: Greg Kroah-Hartman

kprobes: Do not expose probe addresses to non-CAP_SYSLOG

2020-07-16T06:17:27Z

commit 60f7bb66b88b649433bf700acfc60c3f24953871 upstream. The kprobe show() functions were using "current"'s creds instead of the file opener's creds for kallsyms visibility. Fix to use seq_file->file->f_cred. Cc: Masami Hiramatsu Cc: stable@vger.kernel.org Fixes: 81365a947de4 ("kprobes: Show address of kprobes if kallsyms does") Fixes: ffb9bd68ebdb ("kprobes: Show blacklist addresses as same as kallsyms does") Signed-off-by: Kees Cook Signed-off-by: Greg Kroah-Hartman