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- 14 Aug, 2018 5 commits
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Greg Kroah-Hartman authored
BugLink: https://bugs.launchpad.net/bugs/1784382Signed-off-by:
Kleber Sacilotto de Souza <kleber.souza@canonical.com> Signed-off-by:
Khalid Elmously <khalid.elmously@canonical.com>
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Greg Kroah-Hartman authored
BugLink: https://bugs.launchpad.net/bugs/1777389Signed-off-by:
Juerg Haefliger <juergh@canonical.com> Signed-off-by:
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Greg Kroah-Hartman authored
BugLink: https://bugs.launchpad.net/bugs/1777063Signed-off-by:
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Greg Kroah-Hartman authored
BugLink: https://bugs.launchpad.net/bugs/1776177Signed-off-by:
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Greg Kroah-Hartman authored
BugLink: https://bugs.launchpad.net/bugs/1776158Signed-off-by:
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- 08 Jun, 2018 1 commit
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Greg Kroah-Hartman authored
BugLink: https://bugs.launchpad.net/bugs/1775771Signed-off-by:
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- 07 Jun, 2018 2 commits
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Greg Kroah-Hartman authored
BugLink: https://bugs.launchpad.net/bugs/1775477Signed-off-by:
Stefan Bader <stefan.bader@canonical.com> Acked-by:
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Greg Kroah-Hartman authored
BugLink: http://bugs.launchpad.net/bugs/1774173Signed-off-by:
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- 23 May, 2018 3 commits
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Greg Kroah-Hartman authored
BugLink: http://bugs.launchpad.net/bugs/1768825Signed-off-by:
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Greg Kroah-Hartman authored
BugLink: http://bugs.launchpad.net/bugs/1768474Signed-off-by:
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Greg Kroah-Hartman authored
BugLink: http://bugs.launchpad.net/bugs/1768429Signed-off-by:
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- 09 May, 2018 13 commits
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Greg Kroah-Hartman authored
BugLink: http://bugs.launchpad.net/bugs/1765010Signed-off-by:
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Greg Kroah-Hartman authored
BugLink: http://bugs.launchpad.net/bugs/1765007Signed-off-by:
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Greg Kroah-Hartman authored
BugLink: http://bugs.launchpad.net/bugs/1764999Signed-off-by:
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Greg Kroah-Hartman authored
BugLink: http://bugs.launchpad.net/bugs/1764973Signed-off-by:
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Daniel Borkmann authored
BugLink: http://bugs.launchpad.net/bugs/1764973 commit 87e0d4f0 upstream. Prasad reported that he has seen crashes in BPF subsystem with netd on Android with arm64 in the form of (note, the taint is unrelated): [ 4134.721483] Unable to handle kernel paging request at virtual address 800000001 [ 4134.820925] Mem abort info: [ 4134.901283] Exception class = DABT (current EL), IL = 32 bits [ 4135.016736] SET = 0, FnV = 0 [ 4135.119820] EA = 0, S1PTW = 0 [ 4135.201431] Data abort info: [ 4135.301388] ISV = 0, ISS = 0x00000021 [ 4135.359599] CM = 0, WnR = 0 [ 4135.470873] user pgtable: 4k pages, 39-bit VAs, pgd = ffffffe39b946000 [ 4135.499757] [0000000800000001] *pgd=0000000000000000, *pud=0000000000000000 [ 4135.660725] Internal error: Oops: 96000021 [#1] PREEMPT SMP [ 4135.674610] Modules linked in: [ 4135.682883] CPU: 5 PID: 1260 Comm: netd Tainted: G S W 4.14.19+ #1 [ 4135.716188] task: ffffffe39f4aa380 task.stack: ffffff801d4e0000 [ 4135.731599] PC is at bpf_prog_add+0x20/0x68 [ 4135.741746] LR is at bpf_prog_inc+0x20/0x2c [ 4135.751788] pc : [<ffffff94ab7ad584>] lr : [<ffffff94ab7ad638>] pstate: 60400145 [ 4135.769062] sp : ffffff801d4e3ce0 [...] [ 4136.258315] Process netd (pid: 1260, stack limit = 0xffffff801d4e0000) [ 4136.273746] Call trace: [...] [ 4136.442494] 3ca0: ffffff94ab7ad584 0000000060400145 ffffffe3a01bf8f8 0000000000000006 [ 4136.460936] 3cc0: 0000008000000000 ffffff94ab844204 ffffff801d4e3cf0 ffffff94ab7ad584 [ 4136.479241] [<ffffff94ab7ad584>] bpf_prog_add+0x20/0x68 [ 4136.491767] [<ffffff94ab7ad638>] bpf_prog_inc+0x20/0x2c [ 4136.504536] [<ffffff94ab7b5d08>] bpf_obj_get_user+0x204/0x22c [ 4136.518746] [<ffffff94ab7ade68>] SyS_bpf+0x5a8/0x1a88 Android's netd was basically pinning the uid cookie BPF map in BPF fs (/sys/fs/bpf/traffic_cookie_uid_map) and later on retrieving it again resulting in above panic. Issue is that the map was wrongly identified as a prog! Above kernel was compiled with clang 4.0, and it turns out that clang decided to merge the bpf_prog_iops and bpf_map_iops into a single memory location, such that the two i_ops could then not be distinguished anymore. Reason for this miscompilation is that clang has the more aggressive -fmerge-all-constants enabled by default. In fact, clang source code has a comment about it in lib/AST/ExprConstant.cpp on why it is okay to do so: Pointers with different bases cannot represent the same object. (Note that clang defaults to -fmerge-all-constants, which can lead to inconsistent results for comparisons involving the address of a constant; this generally doesn't matter in practice.) The issue never appeared with gcc however, since gcc does not enable -fmerge-all-constants by default and even *explicitly* states in it's option description that using this flag results in non-conforming behavior, quote from man gcc: Languages like C or C++ require each variable, including multiple instances of the same variable in recursive calls, to have distinct locations, so using this option results in non-conforming behavior. There are also various clang bug reports open on that matter [1], where clang developers acknowledge the non-conforming behavior, and refer to disabling it with -fno-merge-all-constants. But even if this gets fixed in clang today, there are already users out there that triggered this. Thus, fix this issue by explicitly adding -fno-merge-all-constants to the kernel's Makefile to generically disable this optimization, since potentially other places in the kernel could subtly break as well. Note, there is also a flag called -fmerge-constants (not supported by clang), which is more conservative and only applies to strings and it's enabled in gcc's -O/-O2/-O3/-Os optimization levels. In gcc's code, the two flags -fmerge-{all-,}constants share the same variable internally, so when disabling it via -fno-merge-all-constants, then we really don't merge any const data (e.g. strings), and text size increases with gcc (14,927,214 -> 14,942,646 for vmlinux.o). $ gcc -fverbose-asm -O2 foo.c -S -o foo.S -> foo.S lists -fmerge-constants under options enabled $ gcc -fverbose-asm -O2 -fno-merge-all-constants foo.c -S -o foo.S -> foo.S doesn't list -fmerge-constants under options enabled $ gcc -fverbose-asm -O2 -fno-merge-all-constants -fmerge-constants foo.c -S -o foo.S -> foo.S lists -fmerge-constants under options enabled Thus, as a workaround we need to set both -fno-merge-all-constants *and* -fmerge-constants in the Makefile in order for text size to stay as is. [1] https://bugs.llvm.org/show_bug.cgi?id=18538Reported-by:
Prasad Sodagudi <psodagud@codeaurora.org> Signed-off-by:
Daniel Borkmann <daniel@iogearbox.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Chenbo Feng <fengc@google.com> Cc: Richard Smith <richard-llvm@metafoo.co.uk> Cc: Chandler Carruth <chandlerc@gmail.com> Cc: linux-kernel@vger.kernel.org Tested-by:
Alexei Starovoitov <ast@kernel.org> Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by:
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Greg Kroah-Hartman authored
BugLink: http://bugs.launchpad.net/bugs/1764762Signed-off-by:
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Greg Kroah-Hartman authored
BugLink: http://bugs.launchpad.net/bugs/1764666Signed-off-by:
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Greg Kroah-Hartman authored
BugLink: http://bugs.launchpad.net/bugs/1764627Signed-off-by:
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Greg Kroah-Hartman authored
BugLink: http://bugs.launchpad.net/bugs/1764367Signed-off-by:
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Greg Kroah-Hartman authored
BugLink: http://bugs.launchpad.net/bugs/1764316Signed-off-by:
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Greg Kroah-Hartman authored
BugLink: http://bugs.launchpad.net/bugs/1762453Signed-off-by:
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Greg Kroah-Hartman authored
BugLink: http://bugs.launchpad.net/bugs/1756866Signed-off-by:
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Josh Poimboeuf authored
BugLink: http://bugs.launchpad.net/bugs/1756866 commit e572d088 upstream. When doing a kernel build with 'make -s', everything is silenced except the objtool build. That's because the tools tree support for silent builds is some combination of missing and broken. Three changes are needed to fix it: - Makefile: propagate '-s' to the sub-make's MAKEFLAGS variable so the tools Makefiles can see it. - tools/scripts/Makefile.include: fix the tools Makefiles' ability to recognize '-s'. The MAKE_VERSION and MAKEFLAGS checks are copied from the top-level Makefile. This silences the "DESCEND objtool" message. - tools/build/Makefile.build: add support to the tools Build files for recognizing '-s'. Again the MAKE_VERSION and MAKEFLAGS checks are copied from the top-level Makefile. This silences all the object compile/link messages. Reported-and-Tested-by:
Peter Zijlstra <peterz@infradead.org> Signed-off-by:
Josh Poimboeuf <jpoimboe@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Michal Marek <mmarek@suse.com> Link: http://lkml.kernel.org/r/e8967562ef640c3ae9a76da4ae0f4e47df737c34.1484799200.git.jpoimboe@redhat.comSigned-off-by:
Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by:
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- 04 Apr, 2018 1 commit
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Greg Kroah-Hartman authored
BugLink: http://bugs.launchpad.net/bugs/1756860Signed-off-by:
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- 03 Apr, 2018 2 commits
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Greg Kroah-Hartman authored
BugLink: http://bugs.launchpad.net/bugs/1756121Signed-off-by:
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Greg Kroah-Hartman authored
BugLink: http://bugs.launchpad.net/bugs/1755509Signed-off-by:
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- 13 Mar, 2018 13 commits
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Greg Kroah-Hartman authored
BugLink: http://bugs.launchpad.net/bugs/1754592Signed-off-by:
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Greg Kroah-Hartman authored
BugLink: http://bugs.launchpad.net/bugs/1754375Signed-off-by:
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Greg Kroah-Hartman authored
BugLink: http://bugs.launchpad.net/bugs/1745266Signed-off-by:
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Greg Kroah-Hartman authored
BugLink: http://bugs.launchpad.net/bugs/1745263Signed-off-by:
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Greg Kroah-Hartman authored
BugLink: http://bugs.launchpad.net/bugs/1745071Signed-off-by:
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Greg Kroah-Hartman authored
BugLink: http://bugs.launchpad.net/bugs/1745069Signed-off-by:
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Linus Torvalds authored
BugLink: http://bugs.launchpad.net/bugs/1745069 commit 3ce120b1 upstream. It appears that hardened gentoo enables "-fstack-check" by default for gcc. That doesn't work _at_all_ for the kernel, because the kernel stack doesn't act like a user stack at all: it's much smaller, and it doesn't auto-expand on use. So the extra "probe one page below the stack" code generated by -fstack-check just breaks the kernel in horrible ways, causing infinite double faults etc. [ I have to say, that the particular code gcc generates looks very stupid even for user space where it works, but that's a separate issue. ] Reported-and-tested-by:
Alexander Tsoy <alexander@tsoy.me> Reported-and-tested-by:
Toralf Förster <toralf.foerster@gmx.de> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Jiri Kosina <jikos@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by:
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Greg Kroah-Hartman authored
BugLink: http://bugs.launchpad.net/bugs/1745054Signed-off-by:
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Greg Kroah-Hartman authored
BugLink: http://bugs.launchpad.net/bugs/1745052Signed-off-by:
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Greg Kroah-Hartman authored
BugLink: http://bugs.launchpad.net/bugs/1745047Signed-off-by:
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Greg Kroah-Hartman authored
BugLink: http://bugs.launchpad.net/bugs/1745046Signed-off-by:
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Greg Kroah-Hartman authored
BugLink: http://bugs.launchpad.net/bugs/1745043Signed-off-by:
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Greg Kroah-Hartman authored
BugLink: http://bugs.launchpad.net/bugs/1744873Signed-off-by:
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