KASAN: slab-out-of-bounds Write in sha1_finup
Subsystems (3)
syzbot
syzbotHello,
syzbot found the following crash on:
HEAD commit: 1c8c5a9d38f6 Merge git://git.kernel.org/pub/scm/linux/kern.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=16289b9f800000 kernel config: https://syzkaller.appspot.com/x/.config?x=2e1a31e8576e013a dashboard link: https://syzkaller.appspot.com/bug?extid=486f97f892efeb2075a3 compiler: gcc (GCC) 8.0.1 20180413 (experimental) userspace arch: i386
syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?x=122bb5df800000
IMPORTANT: if you fix the bug, please add the following tag to the commit:
IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready
IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): bond0: link becomes ready 8021q: adding VLAN 0 to HW filter on device team0
==================================================================
BUG: KASAN: slab-out-of-bounds in put_unaligned_be32 include/linux/unaligned/access_ok.h:60 [inline] BUG: KASAN: slab-out-of-bounds in sha1_base_finish include/crypto/sha1_base.h:102 [inline] BUG: KASAN: slab-out-of-bounds in sha1_finup+0x44e/0x4b0 arch/x86/crypto/sha1_ssse3_glue.c:70 Write of size 4 at addr ffff8801d7130ed8 by task syz-executor0/4761 CPU: 0 PID: 4761 Comm: syz-executor0 Not tainted 4.17.0+ #113 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1b9/0x294 lib/dump_stack.c:113 print_address_description+0x6c/0x20b mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412 __asan_report_store4_noabort+0x17/0x20 mm/kasan/report.c:437 put_unaligned_be32 include/linux/unaligned/access_ok.h:60 [inline] sha1_base_finish include/crypto/sha1_base.h:102 [inline] sha1_finup+0x44e/0x4b0 arch/x86/crypto/sha1_ssse3_glue.c:70 sha1_avx2_finup arch/x86/crypto/sha1_ssse3_glue.c:232 [inline] sha1_avx2_final+0x28/0x30 arch/x86/crypto/sha1_ssse3_glue.c:238 crypto_shash_final+0x104/0x260 crypto/shash.c:152 kdf_ctr security/keys/dh.c:186 [inline] keyctl_dh_compute_kdf security/keys/dh.c:217 [inline] __keyctl_dh_compute+0x1184/0x1bc0 security/keys/dh.c:389 compat_keyctl_dh_compute+0x2c8/0x3e0 security/keys/compat_dh.c:39 __do_compat_sys_keyctl security/keys/compat.c:136 [inline] __se_compat_sys_keyctl security/keys/compat.c:59 [inline] __ia32_compat_sys_keyctl+0x137/0x3b0 security/keys/compat.c:59 do_syscall_32_irqs_on arch/x86/entry/common.c:323 [inline] do_fast_syscall_32+0x345/0xf9b arch/x86/entry/common.c:394 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 RIP: 0023:0xf7fbdcb9 Code: 55 08 8b 88 64 cd ff ff 8b 98 68 cd ff ff 89 c8 85 d2 74 02 89 0a 5b 5d c3 8b 04 24 c3 8b 1c 24 c3 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 002b:00000000ffdb494c EFLAGS: 00000286 ORIG_RAX: 0000000000000120 RAX: ffffffffffffffda RBX: 0000000000000017 RCX: 0000000020000100 RDX: 0000000020a53ffb RSI: 0000000000000005 RDI: 0000000020c61fc8 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 4761: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553 __do_kmalloc mm/slab.c:3718 [inline] __kmalloc+0x14e/0x760 mm/slab.c:3727 kmalloc include/linux/slab.h:518 [inline] keyctl_dh_compute_kdf security/keys/dh.c:211 [inline] __keyctl_dh_compute+0xfe9/0x1bc0 security/keys/dh.c:389 compat_keyctl_dh_compute+0x2c8/0x3e0 security/keys/compat_dh.c:39 __do_compat_sys_keyctl security/keys/compat.c:136 [inline] __se_compat_sys_keyctl security/keys/compat.c:59 [inline] __ia32_compat_sys_keyctl+0x137/0x3b0 security/keys/compat.c:59 do_syscall_32_irqs_on arch/x86/entry/common.c:323 [inline] do_fast_syscall_32+0x345/0xf9b arch/x86/entry/common.c:394 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 Freed by task 1: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kfree+0xd9/0x260 mm/slab.c:3813 acpi_os_free include/acpi/platform/aclinuxex.h:62 [inline] acpi_ns_get_node_unlocked+0x2b1/0x2ee drivers/acpi/acpica/nsutils.c:698 acpi_ns_get_node+0x4d/0x6b drivers/acpi/acpica/nsutils.c:738 acpi_get_handle+0x153/0x24b drivers/acpi/acpica/nsxfname.c:98 acpi_has_method+0x68/0xa0 drivers/acpi/utils.c:555 acpi_device_setup_files+0x393/0x820 drivers/acpi/device_sysfs.c:565 acpi_device_add+0x8af/0x1240 drivers/acpi/scan.c:700 acpi_add_single_object+0xaa5/0x1e70 drivers/acpi/scan.c:1620 acpi_bus_check_add+0x5fa/0xb40 drivers/acpi/scan.c:1860 acpi_ns_walk_namespace+0x224/0x400 drivers/acpi/acpica/nswalk.c:237 acpi_walk_namespace+0xf2/0x12c drivers/acpi/acpica/nsxfeval.c:606 acpi_bus_scan+0x138/0x160 drivers/acpi/scan.c:2041 acpi_scan_init+0x404/0x8df drivers/acpi/scan.c:2198 acpi_init+0x936/0x9fa drivers/acpi/bus.c:1284 do_one_initcall+0x127/0x913 init/main.c:884 do_initcall_level init/main.c:952 [inline] do_initcalls init/main.c:960 [inline] do_basic_setup init/main.c:978 [inline] kernel_init_freeable+0x49b/0x58e init/main.c:1135 kernel_init+0x11/0x1b3 init/main.c:1061 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412 The buggy address belongs to the object at ffff8801d7130ec0 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 24 bytes inside of 32-byte region [ffff8801d7130ec0, ffff8801d7130ee0) The buggy address belongs to the page: page:ffffea00075c4c00 count:1 mapcount:0 mapping:ffff8801d7130000 index:0xffff8801d7130fc1 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffff8801d7130000 ffff8801d7130fc1 0000000100000036 raw: ffffea00076061e0 ffffea0007633a60 ffff8801da8001c0 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801d7130d80: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc ffff8801d7130e00: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
Quoted 1 line
ffff8801d7130e80: fb fb fb fb fc fc fc fc 00 00 00 fc fc fc fc fc
^
ffff8801d7130f00: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
ffff8801d7130f80: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
---
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syzbot
syzbotsyzbot has found a reproducer for the following crash on:
syzbot has found a reproducer for the following crash on:
HEAD commit: 1c8c5a9d38f6 Merge git://git.kernel.org/pub/scm/linux/kern.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=109fbb4f800000 kernel config: https://syzkaller.appspot.com/x/.config?x=4f1acdf888c9d4e9 dashboard link: https://syzkaller.appspot.com/bug?extid=486f97f892efeb2075a3 compiler: gcc (GCC) 8.0.1 20180413 (experimental)
syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?x=11095fef800000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=175de79f800000
IMPORTANT: if you fix the bug, please add the following tag to the commit:
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
==================================================================
BUG: KASAN: slab-out-of-bounds in put_unaligned_be32 include/linux/unaligned/access_ok.h:60 [inline] BUG: KASAN: slab-out-of-bounds in sha1_base_finish include/crypto/sha1_base.h:102 [inline] BUG: KASAN: slab-out-of-bounds in sha1_finup+0x44e/0x4b0 arch/x86/crypto/sha1_ssse3_glue.c:70 Write of size 4 at addr ffff8801d97e1ad8 by task syz-executor437/4553 CPU: 0 PID: 4553 Comm: syz-executor437 Not tainted 4.17.0+ #89 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1b9/0x294 lib/dump_stack.c:113 print_address_description+0x6c/0x20b mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412 __asan_report_store4_noabort+0x17/0x20 mm/kasan/report.c:437 put_unaligned_be32 include/linux/unaligned/access_ok.h:60 [inline] sha1_base_finish include/crypto/sha1_base.h:102 [inline] sha1_finup+0x44e/0x4b0 arch/x86/crypto/sha1_ssse3_glue.c:70 sha1_avx2_finup arch/x86/crypto/sha1_ssse3_glue.c:232 [inline] sha1_avx2_final+0x28/0x30 arch/x86/crypto/sha1_ssse3_glue.c:238 crypto_shash_final+0x104/0x260 crypto/shash.c:152 kdf_ctr security/keys/dh.c:186 [inline] keyctl_dh_compute_kdf security/keys/dh.c:217 [inline] __keyctl_dh_compute+0x1184/0x1bc0 security/keys/dh.c:389 keyctl_dh_compute+0xb9/0x100 security/keys/dh.c:425 __do_sys_keyctl security/keys/keyctl.c:1741 [inline] __se_sys_keyctl security/keys/keyctl.c:1637 [inline] __x64_sys_keyctl+0x12a/0x3b0 security/keys/keyctl.c:1637 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x43ffb9 Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 6b 45 00 00 c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffce5fe4808 EFLAGS: 00000217 ORIG_RAX: 00000000000000fa RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043ffb9 RDX: 0000000020a53ffb RSI: 0000000020000100 RDI: 0000000000000017 RBP: 00000000006ca018 R08: 0000000020c61fc8 R09: 00000000004002c8 R10: 0000000000000005 R11: 0000000000000217 R12: 00000000004018e0 R13: 0000000000401970 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 4553: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553 __do_kmalloc mm/slab.c:3718 [inline] __kmalloc+0x14e/0x760 mm/slab.c:3727 kmalloc include/linux/slab.h:518 [inline] keyctl_dh_compute_kdf security/keys/dh.c:211 [inline] __keyctl_dh_compute+0xfe9/0x1bc0 security/keys/dh.c:389 keyctl_dh_compute+0xb9/0x100 security/keys/dh.c:425 __do_sys_keyctl security/keys/keyctl.c:1741 [inline] __se_sys_keyctl security/keys/keyctl.c:1637 [inline] __x64_sys_keyctl+0x12a/0x3b0 security/keys/keyctl.c:1637 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 2877: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kfree+0xd9/0x260 mm/slab.c:3813 single_release+0x8f/0xb0 fs/seq_file.c:609 __fput+0x353/0x890 fs/file_table.c:209 ____fput+0x15/0x20 fs/file_table.c:243 task_work_run+0x1e4/0x290 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:192 [inline] exit_to_usermode_loop+0x2bd/0x310 arch/x86/entry/common.c:166 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline] syscall_return_slowpath arch/x86/entry/common.c:265 [inline] do_syscall_64+0x6ac/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8801d97e1ac0 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 24 bytes inside of 32-byte region [ffff8801d97e1ac0, ffff8801d97e1ae0) The buggy address belongs to the page: page:ffffea000765f840 count:1 mapcount:0 mapping:ffff8801d97e1000 index:0xffff8801d97e1fc1 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffff8801d97e1000 ffff8801d97e1fc1 0000000100000016 raw: ffffea00076540e0 ffffea000736cda0 ffff8801da8001c0 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801d97e1980: 00 00 00 00 fc fc fc fc 00 fc fc fc fc fc fc fc ffff8801d97e1a00: 00 00 00 00 fc fc fc fc fb fb fb fb fc fc fc fc
Quoted 1 line
ffff8801d97e1a80: fb fb fb fb fc fc fc fc 00 00 00 fc fc fc fc fc
^
ffff8801d97e1b00: fb fb fb fb fc fc fc fc 00 fc fc fc fc fc fc fc
ffff8801d97e1b80: 00 fc fc fc fc fc fc fc 00 fc fc fc fc fc fc fc
==================================================================
PATCH 1/1 dh key: fix rounding up KDF output length
In reply to syzbotFrom: Eric Biggers <[email protected]>
Commit 383203eff718 ("dh key: get rid of stack allocated array") changed kdf_ctr() to assume that the length of key material to derive is a multiple of the digest size. The length was supposed to be rounded up accordingly. However, the round_up() macro was used which only gives the correct result on power-of-2 arguments, whereas not all hash algorithms have power-of-2 digest sizes. In some cases this resulted in a write past the end of the 'outbuf' buffer.
Fix it by switching to roundup(), which works for non-power-of-2 inputs.
--- security/keys/dh.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
security/keys/dh.c +4 -2
@@ -142,6 +142,8 @@ static void kdf_dealloc(struct kdf_sdesc *sdesc)* The src pointer is defined as Z || other info where Z is the shared secret * from DH and other info is an arbitrary string (see SP800-56A section * 5.8.1.2). +* +* 'dlen' must be a multiple of the digest size. */ static int kdf_ctr (struct kdf_sdesc *sdesc,const u8 *src,unsigned int slen,u8 *dst,unsigned int dlen,unsigned int zlen)
@@ -205,8 +207,8 @@ static int keyctl_dh_compute_kdf(struct kdf_sdesc *sdesc, {uint8_t *outbuf =NULL ;int ret; -size_t outbuf_len =round_up (buflen, -crypto_shash_digestsize (sdesc->shash.tfm)); +size_t outbuf_len =roundup (buflen, +crypto_shash_digestsize (sdesc->shash.tfm)); outbuf =kmalloc (outbuf_len,GFP_KERNEL );if (!outbuf) {
Signature · 1 line
2.17.1.1185.g55be947832-goog
Re: [PATCH] dh key: fix rounding up KDF output length
Quoted 11 lines · Eric Biggers
From: Eric Biggers <[email protected]>
Commit
383203eff718("dh key: get rid of stack allocated array") changedkdf_ctr()to assume that the length of key material to derive is a multiple of the digest size. The length was supposed to be rounded up accordingly. However, theround_up()macro was used which only gives the correct result on power-of-2 arguments, whereas not all hash algorithms have power-of-2 digest sizes. In some cases this resulted in a write past the end of the 'outbuf' buffer.Fix it by switching to
roundup(), which works for non-power-of-2 inputs.
round_up() vs roundup(). Wow, that's not confusing. :( I wonder if we should rename the former to roundup_pow2() or something?
Quoted 6 lines
Reported-by [email protected]Reported-by [email protected]Reported-by [email protected]Reported-by [email protected]Fixes 383203eff718 ("dh key: get rid of stack allocated array")Signed-off-by Eric Biggers <[email protected]>
Regardless:
-Kees
Quoted 31 lines
--- security/keys/dh.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)security/keys/dh.c +4
-3@@ -142,6 +142,8 @@ static void kdf_dealloc(struct kdf_sdesc *sdesc)* The src pointer is defined as Z || other info where Z is the shared secret * from DH and other info is an arbitrary string (see SP800-56A section * 5.8.1.2). +* +* 'dlen' must be a multiple of the digest size. */ static int kdf_ctr (struct kdf_sdesc *sdesc,const u8 *src,unsigned int slen,u8 *dst,unsigned int dlen,unsigned int zlen)@@ -205,8 +207,8 @@ static int keyctl_dh_compute_kdf(struct kdf_sdesc *sdesc, {uint8_t *outbuf =NULL ;int ret; -size_t outbuf_len =round_up (buflen, -crypto_shash_digestsize (sdesc->shash.tfm)); +size_t outbuf_len =roundup (buflen, +crypto_shash_digestsize (sdesc->shash.tfm)); outbuf =kmalloc (outbuf_len,GFP_KERNEL );if (!outbuf) { --2.17.1.1185.g55be947832-goog
Signature · 2 lines
Kees Cook Pixel Security
James Morris
maintainerRe: [PATCH] dh key: fix rounding up KDF output length
Quoted 11 lines · Kees Cook
Quoted 10 lines · Eric Biggers
From: Eric Biggers <[email protected]>
Commit
383203eff718("dh key: get rid of stack allocated array") changedkdf_ctr()to assume that the length of key material to derive is a multiple of the digest size. The length was supposed to be rounded up accordingly. However, theround_up()macro was used which only gives the correct result on power-of-2 arguments, whereas not all hash algorithms have power-of-2 digest sizes. In some cases this resulted in a write past the end of the 'outbuf' buffer.
Quoted 4 lines
Quoted 1 line
Fix it by switching to
roundup(), which works for non-power-of-2 inputs.
round_up()vsroundup(). Wow, that's not confusing. :( I wonder if we should rename the former toroundup_pow2()or something?
Good idea, in a separate patch(set).
Signature · 2 lines
James Morris <[email protected]>
Re: [PATCH] dh key: fix rounding up KDF output length
In reply to Kees CookQuoted 11 lines · Kees Cook
Quoted 10 lines · Eric Biggers
From: Eric Biggers <[email protected]>
Commit
383203eff718("dh key: get rid of stack allocated array") changedkdf_ctr()to assume that the length of key material to derive is a multiple of the digest size. The length was supposed to be rounded up accordingly. However, theround_up()macro was used which only gives the correct result on power-of-2 arguments, whereas not all hash algorithms have power-of-2 digest sizes. In some cases this resulted in a write past the end of the 'outbuf' buffer.
Quoted 4 lines
Quoted 1 line
Fix it by switching to
roundup(), which works for non-power-of-2 inputs.
round_up()vsroundup(). Wow, that's not confusing. :( I wonder if we should rename the former toroundup_pow2()or something?
Yes, it's very confusing, and I wish the names were clearer, or that there was one macro that just did the right thing (but then the power-of-2 optimization could only be done for constants, where it might not be necessary anyway). roundup_pow2() would still be confused with roundup_pow_of_two(), unfortunately.
Eric
Re: [PATCH] dh key: fix rounding up KDF output length
In reply to Eric BiggersQuoted 10 lines · Eric Biggers
From: Eric Biggers <[email protected]>
Commit
383203eff718("dh key: get rid of stack allocated array") changedkdf_ctr()to assume that the length of key material to derive is a multiple of the digest size. The length was supposed to be rounded up accordingly. However, theround_up()macro was used which only gives the correct result on power-of-2 arguments, whereas not all hash algorithms have power-of-2 digest sizes. In some cases this resulted in a write past the end of the 'outbuf' buffer.
Quoted 8 lines
Fix it by switching to
roundup(), which works for non-power-of-2 inputs.Reported-by [email protected]Reported-by [email protected]Reported-by [email protected]Reported-by [email protected]Fixes 383203eff718 ("dh key: get rid of stack allocated array")Signed-off-by Eric Biggers <[email protected]>
Arg, thanks.
Re: [PATCH] dh key: fix rounding up KDF output length
In reply to Eric BiggersQuoted 9 lines · Eric Biggers
Commit
383203eff718("dh key: get rid of stack allocated array") changedkdf_ctr()to assume that the length of key material to derive is a multiple of the digest size. The length was supposed to be rounded up accordingly. However, theround_up()macro was used which only gives the correct result on power-of-2 arguments, whereas not all hash algorithms have power-of-2 digest sizes. In some cases this resulted in a write past the end of the 'outbuf' buffer.Fix it by switching to
roundup(), which works for non-power-of-2 inputs.
Applied.
Eric Biggers
AppliedRe: [PATCH] dh key: fix rounding up KDF output length
Hi David,
Quoted 10 lines · David Howells
Quoted 8 lines · Eric Biggers
Commit
383203eff718("dh key: get rid of stack allocated array") changedkdf_ctr()to assume that the length of key material to derive is a multiple of the digest size. The length was supposed to be rounded up accordingly. However, theround_up()macro was used which only gives the correct result on power-of-2 arguments, whereas not all hash algorithms have power-of-2 digest sizes. In some cases this resulted in a write past the end of the 'outbuf' buffer.
Quoted 3 lines
Quoted 1 line
Fix it by switching to
roundup(), which works for non-power-of-2 inputs.Applied.
Applied to where? When are you planning to send this to Linus? Note that this was a regression from v4.17 to v4.18-rc1.
Thanks,
- Eric