kvm_pv_send_ipi in arch/x86/kvm/lapic.c in the Linux kernel through 4.19.2 allows local users to cause a denial of service (NULL pointer dereference and BUG) via crafted system calls that reach a situation where the apic map is uninitialized.

An issue was discovered in JasPer 2.0.14. There is a NULL pointer dereference in the function jp2_decode in libjasper/jp2/jp2_dec.c, leading to a denial of service.

The vcpu_scan_ioapic function in arch/x86/kvm/x86.c in the Linux kernel through 4.19.2 allows local users to cause a denial of service (NULL pointer dereference and BUG) via crafted system calls that reach a situation where ioapic is uninitialized.

An issue was discovered in LibTIFF 4.0.9. There is a NULL pointer dereference in the function LZWDecode in the file tif_lzw.c.

Multiple race conditions in fs/pipe.c in the Linux kernel before 2.6.32-rc6 allow local users to cause a denial of service (NULL pointer dereference and system crash) or gain privileges by attempting to open an anonymous pipe via a /proc/*/fd/ pathname.

chmd_read_headers in mspack/chmd.c in libmspack before 0.8alpha accepts a filename that has '\0' as its first or second character (such as the "/\0" name).

An issue was discovered in JasPer 2.0.14. There is a NULL pointer dereference in the function ras_putdatastd in ras/ras_enc.c.

NVIDIA GPU Display Driver for Linux contains a vulnerability in the kernel mode layer, where an unprivileged regular user can cause a null-pointer dereference, which may lead to denial of service.

An issue was discovered in Poppler 0.71.0. There is a NULL pointer dereference in goo/GooString.h, will lead to denial of service, as demonstrated by utils/pdfdetach.cc not validating a filename of an embedded file before constructing a save path.

The ATI Rage 128 (aka r128) driver in the Linux kernel before 2.6.31-git11 does not properly verify Concurrent Command Engine (CCE) state initialization, which allows local users to cause a denial of service (NULL pointer dereference and system crash) or possibly gain privileges via unspecified ioctl calls.

The load_flat_shared_library function in fs/binfmt_flat.c in the flat subsystem in the Linux kernel before 2.6.31-rc6 allows local users to cause a denial of service (NULL pointer dereference and system crash) or possibly have unspecified other impact by executing a shared flat binary, which triggers an access of an "uninitialized cred pointer."

A NULL pointer dereference vulnerability exists in the xpath.c:xmlXPathCompOpEval() function of libxml2 through 2.9.8 when parsing an invalid XPath expression in the XPATH_OP_AND or XPATH_OP_OR case. Applications processing untrusted XSL format inputs with the use of the libxml2 library may be vulnerable to a denial of service attack due to a crash of the application.

The udp_sendmsg function in the UDP implementation in (1) net/ipv4/udp.c and (2) net/ipv6/udp.c in the Linux kernel before 2.6.19 allows local users to gain privileges or cause a denial of service (NULL pointer dereference and system crash) via vectors involving the MSG_MORE flag and a UDP socket.

A null pointer dereference vulnerability was found in dpll_pin_parent_pin_set() in drivers/dpll/dpll_netlink.c in the Digital Phase Locked Loop (DPLL) subsystem in the Linux kernel. This issue could be exploited to trigger a denial of service.

A NULL pointer dereference in the function _TIFFmemcmp at tif_unix.c (called from TIFFWriteDirectoryTagTransferfunction) in LibTIFF 4.0.9 allows an attacker to cause a denial-of-service through a crafted tiff file. This vulnerability can be triggered by the executable tiffcp.

NVIDIA vGPU software for Linux contains a vulnerability where the software can dereference a NULL pointer. A successful exploit of this vulnerability might lead to denial of service and undefined behavior in the vGPU plugin.

A flaw was found in the Linux kernel's NFS implementation, all versions 3.x and all versions 4.x up to 4.20. An attacker, who is able to mount an exported NFS filesystem, is able to trigger a null pointer dereference by using an invalid NFS sequence. This can panic the machine and deny access to the NFS server. Any outstanding disk writes to the NFS server will be lost.

_set_key in agent/helpers/table_container.c in Net-SNMP before 5.8 has a NULL Pointer Exception bug that can be used by an authenticated attacker to remotely cause the instance to crash via a crafted UDP packet, resulting in Denial of Service.

ssl/s3_pkt.c in OpenSSL before 0.9.8i allows remote attackers to cause a denial of service (NULL pointer dereference and daemon crash) via a DTLS ChangeCipherSpec packet that occurs before ClientHello.

Unchecked NULL pointer usage when parsing invalid atoms in ExprResolveLhs in xkbcomp/expr.c in xkbcommon before 0.8.2 could be used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file, because lookup failures are mishandled.

In ImageMagick 7.0.7-29 and earlier, a missing NULL check in ReadOneJNGImage in coders/png.c allows an attacker to cause a denial of service (WriteBlob assertion failure and application exit) via a crafted file.

A null pointer dereference vulnerability was found in nft_dynset_init() in net/netfilter/nft_dynset.c in nf_tables in the Linux kernel. This issue may allow a local attacker with CAP_NET_ADMIN user privilege to trigger a denial of service.

Unchecked NULL pointer usage in xkbcommon before 0.8.1 could be used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file, because the XkbFile for an xkb_geometry section was mishandled.

A Null pointer dereference problem was found in ida_free in lib/idr.c in the Linux Kernel. This issue may allow an attacker using this library to cause a denial of service problem due to a missing check at a function return.

Unchecked NULL pointer usage when handling invalid aliases in CopyKeyAliasesToKeymap in xkbcomp/keycodes.c in xkbcommon before 0.8.1 could be used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file.

Unchecked NULL pointer usage in ExprResolveLhs in xkbcomp/expr.c in xkbcommon before 0.8.2 could be used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file that triggers an xkb_intern_atom failure.

Unchecked NULL pointer usage in xkbcommon before 0.8.1 could be used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file, because geometry tokens were desupported incorrectly.

In GNOME GLib 2.56.1, g_markup_parse_context_end_parse() in gmarkup.c has a NULL pointer dereference.

Unchecked NULL pointer usage in resolve_keysym in xkbcomp/parser.y in xkbcommon before 0.8.2 could be used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file, because a map access attempt can occur for a map that was never created.

Samba from version 4.0.0 and before versions 4.7.12, 4.8.7, 4.9.3 is vulnerable to a denial of service. During the processing of an LDAP search before Samba's AD DC returns the LDAP entries to the client, the entries are cached in a single memory object with a maximum size of 256MB. When this size is reached, the Samba process providing the LDAP service will follow the NULL pointer, terminating the process. There is no further vulnerability associated with this issue, merely a denial of service.

A null pointer dereference flaw was found in the nft_inner.c functionality of netfilter in the Linux kernel. This issue could allow a local user to crash the system or escalate their privileges on the system.

Unchecked NULL pointer usage in LookupModMask in xkbcomp/expr.c in xkbcommon before 0.8.2 could be used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file with invalid virtual modifiers.

The dtls1_retrieve_buffered_fragment function in ssl/d1_both.c in OpenSSL before 1.0.0 Beta 2 allows remote attackers to cause a denial of service (NULL pointer dereference and daemon crash) via an out-of-sequence DTLS handshake message, related to a "fragment bug."

A flaw was found in the Linux kernel's NVMe driver. This issue may allow an unauthenticated malicious actor to send a set of crafted TCP packages when using NVMe over TCP, leading the NVMe driver to a NULL pointer dereference in the NVMe driver, causing kernel panic and a denial of service.

An issue was discovered in the Linux kernel through 4.17.10. There is an invalid pointer dereference in __del_reloc_root() in fs/btrfs/relocation.c when mounting a crafted btrfs image, related to removing reloc rb_trees when reloc control has not been initialized.

A null pointer dereference flaw was found in the Linux kernel API for the cryptographic algorithm scatterwalk functionality. This issue occurs when a user constructs a malicious packet with specific socket configuration, which could allow a local user to crash the system or escalate their privileges on the system.

An issue was discovered in the Linux kernel through 4.17.10. There is a NULL pointer dereference in fscrypt_do_page_crypto() in fs/crypto/crypto.c when operating on a file in a corrupted f2fs image.

gdImageClone in gd.c in libgd 2.1.0-rc2 through 2.2.5 has a NULL pointer dereference allowing attackers to crash an application via a specific function call sequence. Only affects PHP when linked with an external libgd (not bundled).

In the Linux kernel, the following vulnerability has been resolved: media: hantro: Check whether reset op is defined before use The i.MX8MM/N/P does not define the .reset op since reset of the VPU is done by genpd. Check whether the .reset op is defined before calling it to avoid NULL pointer dereference. Note that the Fixes tag is set to the commit which removed the reset op from i.MX8M Hantro G2 implementation, this is because before this commit all the implementations did define the .reset op.

In the Linux kernel, the following vulnerability has been resolved: Add exception protection processing for vd in axi_chan_handle_err function Since there is no protection for vd, a kernel panic will be triggered here in exceptional cases. You can refer to the processing of axi_chan_block_xfer_complete function The triggered kernel panic is as follows: [ 67.848444] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000060 [ 67.848447] Mem abort info: [ 67.848449] ESR = 0x96000004 [ 67.848451] EC = 0x25: DABT (current EL), IL = 32 bits [ 67.848454] SET = 0, FnV = 0 [ 67.848456] EA = 0, S1PTW = 0 [ 67.848458] Data abort info: [ 67.848460] ISV = 0, ISS = 0x00000004 [ 67.848462] CM = 0, WnR = 0 [ 67.848465] user pgtable: 4k pages, 48-bit VAs, pgdp=00000800c4c0b000 [ 67.848468] [0000000000000060] pgd=0000000000000000, p4d=0000000000000000 [ 67.848472] Internal error: Oops: 96000004 [#1] SMP [ 67.848475] Modules linked in: dmatest [ 67.848479] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.10.100-emu_x2rc+ #11 [ 67.848483] pstate: 62000085 (nZCv daIf -PAN -UAO +TCO BTYPE=--) [ 67.848487] pc : axi_chan_handle_err+0xc4/0x230 [ 67.848491] lr : axi_chan_handle_err+0x30/0x230 [ 67.848493] sp : ffff0803fe55ae50 [ 67.848495] x29: ffff0803fe55ae50 x28: ffff800011212200 [ 67.848500] x27: ffff0800c42c0080 x26: ffff0800c097c080 [ 67.848504] x25: ffff800010d33880 x24: ffff80001139d850 [ 67.848508] x23: ffff0800c097c168 x22: 0000000000000000 [ 67.848512] x21: 0000000000000080 x20: 0000000000002000 [ 67.848517] x19: ffff0800c097c080 x18: 0000000000000000 [ 67.848521] x17: 0000000000000000 x16: 0000000000000000 [ 67.848525] x15: 0000000000000000 x14: 0000000000000000 [ 67.848529] x13: 0000000000000000 x12: 0000000000000040 [ 67.848533] x11: ffff0800c0400248 x10: ffff0800c040024a [ 67.848538] x9 : ffff800010576cd4 x8 : ffff0800c0400270 [ 67.848542] x7 : 0000000000000000 x6 : ffff0800c04003e0 [ 67.848546] x5 : ffff0800c0400248 x4 : ffff0800c4294480 [ 67.848550] x3 : dead000000000100 x2 : dead000000000122 [ 67.848555] x1 : 0000000000000100 x0 : ffff0800c097c168 [ 67.848559] Call trace: [ 67.848562] axi_chan_handle_err+0xc4/0x230 [ 67.848566] dw_axi_dma_interrupt+0xf4/0x590 [ 67.848569] __handle_irq_event_percpu+0x60/0x220 [ 67.848573] handle_irq_event+0x64/0x120 [ 67.848576] handle_fasteoi_irq+0xc4/0x220 [ 67.848580] __handle_domain_irq+0x80/0xe0 [ 67.848583] gic_handle_irq+0xc0/0x138 [ 67.848585] el1_irq+0xc8/0x180 [ 67.848588] arch_cpu_idle+0x14/0x2c [ 67.848591] default_idle_call+0x40/0x16c [ 67.848594] do_idle+0x1f0/0x250 [ 67.848597] cpu_startup_entry+0x2c/0x60 [ 67.848600] rest_init+0xc0/0xcc [ 67.848603] arch_call_rest_init+0x14/0x1c [ 67.848606] start_kernel+0x4cc/0x500 [ 67.848610] Code: eb0002ff 9a9f12d6 f2fbd5a2 f2fbd5a3 (a94602c1) [ 67.848613] ---[ end trace 585a97036f88203a ]---

In the Linux kernel, the following vulnerability has been resolved: vfio/mdev: Fix a null-ptr-deref bug for mdev_unregister_parent() Inject fault while probing mdpy.ko, if kstrdup() of create_dir() fails in kobject_add_internal() in kobject_init_and_add() in mdev_type_add() in parent_create_sysfs_files(), it will return 0 and probe successfully. And when rmmod mdpy.ko, the mdpy_dev_exit() will call mdev_unregister_parent(), the mdev_type_remove() may traverse uninitialized parent->types[i] in parent_remove_sysfs_files(), and it will cause below null-ptr-deref. If mdev_type_add() fails, return the error code and kset_unregister() to fix the issue. general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] CPU: 2 PID: 10215 Comm: rmmod Tainted: G W N 6.6.0-rc2+ #20 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 RIP: 0010:__kobject_del+0x62/0x1c0 Code: 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 51 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 6b 28 48 8d 7d 10 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 24 01 00 00 48 8b 75 10 48 89 df 48 8d 6b 3c e8 RSP: 0018:ffff88810695fd30 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: ffffffffa0270268 RCX: 0000000000000000 RDX: 0000000000000002 RSI: 0000000000000004 RDI: 0000000000000010 RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed10233a4ef1 R10: ffff888119d2778b R11: 0000000063666572 R12: 0000000000000000 R13: fffffbfff404e2d4 R14: dffffc0000000000 R15: ffffffffa0271660 FS: 00007fbc81981540(0000) GS:ffff888119d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc14a142dc0 CR3: 0000000110a62003 CR4: 0000000000770ee0 DR0: ffffffff8fb0bce8 DR1: ffffffff8fb0bce9 DR2: ffffffff8fb0bcea DR3: ffffffff8fb0bceb DR6: 00000000fffe0ff0 DR7: 0000000000000600 PKRU: 55555554 Call Trace: <TASK> ? die_addr+0x3d/0xa0 ? exc_general_protection+0x144/0x220 ? asm_exc_general_protection+0x22/0x30 ? __kobject_del+0x62/0x1c0 kobject_del+0x32/0x50 parent_remove_sysfs_files+0xd6/0x170 [mdev] mdev_unregister_parent+0xfb/0x190 [mdev] ? mdev_register_parent+0x270/0x270 [mdev] ? find_module_all+0x9d/0xe0 mdpy_dev_exit+0x17/0x63 [mdpy] __do_sys_delete_module.constprop.0+0x2fa/0x4b0 ? module_flags+0x300/0x300 ? __fput+0x4e7/0xa00 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 RIP: 0033:0x7fbc813221b7 Code: 73 01 c3 48 8b 0d d1 8c 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 b0 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d a1 8c 2c 00 f7 d8 64 89 01 48 RSP: 002b:00007ffe780e0648 EFLAGS: 00000206 ORIG_RAX: 00000000000000b0 RAX: ffffffffffffffda RBX: 00007ffe780e06a8 RCX: 00007fbc813221b7 RDX: 000000000000000a RSI: 0000000000000800 RDI: 000055e214df9b58 RBP: 000055e214df9af0 R08: 00007ffe780df5c1 R09: 0000000000000000 R10: 00007fbc8139ecc0 R11: 0000000000000206 R12: 00007ffe780e0870 R13: 00007ffe780e0ed0 R14: 000055e214df9260 R15: 000055e214df9af0 </TASK> Modules linked in: mdpy(-) mdev vfio_iommu_type1 vfio [last unloaded: mdpy] Dumping ftrace buffer: (ftrace buffer empty) ---[ end trace 0000000000000000 ]--- RIP: 0010:__kobject_del+0x62/0x1c0 Code: 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 51 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 6b 28 48 8d 7d 10 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 24 01 00 00 48 8b 75 10 48 89 df 48 8d 6b 3c e8 RSP: 0018:ffff88810695fd30 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: ffffffffa0270268 RCX: 0000000000000000 RDX: 0000000000000002 RSI: 0000000000000004 RDI: 0000000000000010 RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed10233a4ef1 R10: ffff888119d2778b R11: 0000000063666572 R12: 0000000000000000 R13: fffffbfff404e2d4 R14: dffffc0000000000 R15: ffffffffa0271660 FS: 00007fbc81981540(0000) GS:ffff888119d00000(000 ---truncated---

In the Linux kernel, the following vulnerability has been resolved: clk: mediatek: clk-mt6765: Add check for mtk_alloc_clk_data Add the check for the return value of mtk_alloc_clk_data() in order to avoid NULL pointer dereference.

In the Linux kernel, the following vulnerability has been resolved: clk: mediatek: clk-mt6797: Add check for mtk_alloc_clk_data Add the check for the return value of mtk_alloc_clk_data() in order to avoid NULL pointer dereference.

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: btusb: Add date->evt_skb is NULL check fix crash because of null pointers [ 6104.969662] BUG: kernel NULL pointer dereference, address: 00000000000000c8 [ 6104.969667] #PF: supervisor read access in kernel mode [ 6104.969668] #PF: error_code(0x0000) - not-present page [ 6104.969670] PGD 0 P4D 0 [ 6104.969673] Oops: 0000 [#1] SMP NOPTI [ 6104.969684] RIP: 0010:btusb_mtk_hci_wmt_sync+0x144/0x220 [btusb] [ 6104.969688] RSP: 0018:ffffb8d681533d48 EFLAGS: 00010246 [ 6104.969689] RAX: 0000000000000000 RBX: ffff8ad560bb2000 RCX: 0000000000000006 [ 6104.969691] RDX: 0000000000000000 RSI: ffffb8d681533d08 RDI: 0000000000000000 [ 6104.969692] RBP: ffffb8d681533d70 R08: 0000000000000001 R09: 0000000000000001 [ 6104.969694] R10: 0000000000000001 R11: 00000000fa83b2da R12: ffff8ad461d1d7c0 [ 6104.969695] R13: 0000000000000000 R14: ffff8ad459618c18 R15: ffffb8d681533d90 [ 6104.969697] FS: 00007f5a1cab9d40(0000) GS:ffff8ad578200000(0000) knlGS:00000 [ 6104.969699] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 6104.969700] CR2: 00000000000000c8 CR3: 000000018620c001 CR4: 0000000000760ef0 [ 6104.969701] PKRU: 55555554 [ 6104.969702] Call Trace: [ 6104.969708] btusb_mtk_shutdown+0x44/0x80 [btusb] [ 6104.969732] hci_dev_do_close+0x470/0x5c0 [bluetooth] [ 6104.969748] hci_rfkill_set_block+0x56/0xa0 [bluetooth] [ 6104.969753] rfkill_set_block+0x92/0x160 [ 6104.969755] rfkill_fop_write+0x136/0x1e0 [ 6104.969759] __vfs_write+0x18/0x40 [ 6104.969761] vfs_write+0xdf/0x1c0 [ 6104.969763] ksys_write+0xb1/0xe0 [ 6104.969765] __x64_sys_write+0x1a/0x20 [ 6104.969769] do_syscall_64+0x51/0x180 [ 6104.969771] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 6104.969773] RIP: 0033:0x7f5a21f18fef [ 6104.9] RSP: 002b:00007ffeefe39010 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 [ 6104.969780] RAX: ffffffffffffffda RBX: 000055c10a7560a0 RCX: 00007f5a21f18fef [ 6104.969781] RDX: 0000000000000008 RSI: 00007ffeefe39060 RDI: 0000000000000012 [ 6104.969782] RBP: 00007ffeefe39060 R08: 0000000000000000 R09: 0000000000000017 [ 6104.969784] R10: 00007ffeefe38d97 R11: 0000000000000293 R12: 0000000000000002 [ 6104.969785] R13: 00007ffeefe39220 R14: 00007ffeefe391a0 R15: 000055c10a72acf0

In the Linux kernel, the following vulnerability has been resolved: apparmor: avoid crash when parsed profile name is empty When processing a packed profile in unpack_profile() described like "profile :ns::samba-dcerpcd /usr/lib*/samba/{,samba/}samba-dcerpcd {...}" a string ":samba-dcerpcd" is unpacked as a fully-qualified name and then passed to aa_splitn_fqname(). aa_splitn_fqname() treats ":samba-dcerpcd" as only containing a namespace. Thus it returns NULL for tmpname, meanwhile tmpns is non-NULL. Later aa_alloc_profile() crashes as the new profile name is NULL now. general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 6 PID: 1657 Comm: apparmor_parser Not tainted 6.7.0-rc2-dirty #16 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-3-gd478f380-rebuilt.opensuse.org 04/01/2014 RIP: 0010:strlen+0x1e/0xa0 Call Trace: <TASK> ? strlen+0x1e/0xa0 aa_policy_init+0x1bb/0x230 aa_alloc_profile+0xb1/0x480 unpack_profile+0x3bc/0x4960 aa_unpack+0x309/0x15e0 aa_replace_profiles+0x213/0x33c0 policy_update+0x261/0x370 profile_replace+0x20e/0x2a0 vfs_write+0x2af/0xe00 ksys_write+0x126/0x250 do_syscall_64+0x46/0xf0 entry_SYSCALL_64_after_hwframe+0x6e/0x76 </TASK> ---[ end trace 0000000000000000 ]--- RIP: 0010:strlen+0x1e/0xa0 It seems such behaviour of aa_splitn_fqname() is expected and checked in other places where it is called (e.g. aa_remove_profiles). Well, there is an explicit comment "a ns name without a following profile is allowed" inside. AFAICS, nothing can prevent unpacked "name" to be in form like ":samba-dcerpcd" - it is passed from userspace. Deny the whole profile set replacement in such case and inform user with EPROTO and an explaining message. Found by Linux Verification Center (linuxtesting.org).

In the Linux kernel, the following vulnerability has been resolved: net: fix NULL pointer in skb_segment_list Commit 3a1296a38d0c ("net: Support GRO/GSO fraglist chaining.") introduced UDP listifyed GRO. The segmentation relies on frag_list being untouched when passing through the network stack. This assumption can be broken sometimes, where frag_list itself gets pulled into linear area, leaving frag_list being NULL. When this happens it can trigger following NULL pointer dereference, and panic the kernel. Reverse the test condition should fix it. [19185.577801][ C1] BUG: kernel NULL pointer dereference, address: ... [19185.663775][ C1] RIP: 0010:skb_segment_list+0x1cc/0x390 ... [19185.834644][ C1] Call Trace: [19185.841730][ C1] <TASK> [19185.848563][ C1] __udp_gso_segment+0x33e/0x510 [19185.857370][ C1] inet_gso_segment+0x15b/0x3e0 [19185.866059][ C1] skb_mac_gso_segment+0x97/0x110 [19185.874939][ C1] __skb_gso_segment+0xb2/0x160 [19185.883646][ C1] udp_queue_rcv_skb+0xc3/0x1d0 [19185.892319][ C1] udp_unicast_rcv_skb+0x75/0x90 [19185.900979][ C1] ip_protocol_deliver_rcu+0xd2/0x200 [19185.910003][ C1] ip_local_deliver_finish+0x44/0x60 [19185.918757][ C1] __netif_receive_skb_one_core+0x8b/0xa0 [19185.927834][ C1] process_backlog+0x88/0x130 [19185.935840][ C1] __napi_poll+0x27/0x150 [19185.943447][ C1] net_rx_action+0x27e/0x5f0 [19185.951331][ C1] ? mlx5_cq_tasklet_cb+0x70/0x160 [mlx5_core] [19185.960848][ C1] __do_softirq+0xbc/0x25d [19185.968607][ C1] irq_exit_rcu+0x83/0xb0 [19185.976247][ C1] common_interrupt+0x43/0xa0 [19185.984235][ C1] asm_common_interrupt+0x22/0x40 ... [19186.094106][ C1] </TASK>

In the Linux kernel, the following vulnerability has been resolved: bpf: support non-r10 register spill/fill to/from stack in precision tracking Use instruction (jump) history to record instructions that performed register spill/fill to/from stack, regardless if this was done through read-only r10 register, or any other register after copying r10 into it *and* potentially adjusting offset. To make this work reliably, we push extra per-instruction flags into instruction history, encoding stack slot index (spi) and stack frame number in extra 10 bit flags we take away from prev_idx in instruction history. We don't touch idx field for maximum performance, as it's checked most frequently during backtracking. This change removes basically the last remaining practical limitation of precision backtracking logic in BPF verifier. It fixes known deficiencies, but also opens up new opportunities to reduce number of verified states, explored in the subsequent patches. There are only three differences in selftests' BPF object files according to veristat, all in the positive direction (less states). File Program Insns (A) Insns (B) Insns (DIFF) States (A) States (B) States (DIFF) -------------------------------------- ------------- --------- --------- ------------- ---------- ---------- ------------- test_cls_redirect_dynptr.bpf.linked3.o cls_redirect 2987 2864 -123 (-4.12%) 240 231 -9 (-3.75%) xdp_synproxy_kern.bpf.linked3.o syncookie_tc 82848 82661 -187 (-0.23%) 5107 5073 -34 (-0.67%) xdp_synproxy_kern.bpf.linked3.o syncookie_xdp 85116 84964 -152 (-0.18%) 5162 5130 -32 (-0.62%) Note, I avoided renaming jmp_history to more generic insn_hist to minimize number of lines changed and potential merge conflicts between bpf and bpf-next trees. Notice also cur_hist_entry pointer reset to NULL at the beginning of instruction verification loop. This pointer avoids the problem of relying on last jump history entry's insn_idx to determine whether we already have entry for current instruction or not. It can happen that we added jump history entry because current instruction is_jmp_point(), but also we need to add instruction flags for stack access. In this case, we don't want to entries, so we need to reuse last added entry, if it is present. Relying on insn_idx comparison has the same ambiguity problem as the one that was fixed recently in [0], so we avoid that. [0] https://patchwork.kernel.org/project/netdevbpf/patch/20231110002638.4168352-3-andrii@kernel.org/