>Synopsis: pax(1) gets stuck in a loop creating intermediate directories
>Category: user
>Environment:
System : OpenBSD 5.8
Details : OpenBSD 5.8 (GENERIC.MP) #1236: Sun Aug 16 02:31:04 MDT
2015
dera...@amd64.openbsd.org:/usr/src/sys/arch/amd64/compile/GENERIC.MP
Architecture: OpenBSD.amd64
Machine : amd64
>Description:
Please note I could only test this on a -stable machine.
pax(1) gets stuck in an infinite loop when recreating intermediate
directories from a pathname ending with '/' while extracting a cpio
archive
>How-To-Repeat:
mkdir -p /tmp/foo/bar
# Note the '/' at the end of "/tmp/foo/bar/" below
find /tmp/foo/bar/ | pax -wx cpio > /tmp/foobar.cpio
# pax -r below never exits
rm -r /tmp/foo && pax -r < /tmp/foobar.cpio
>Fix:
I did some digging and it seems pax gets stuck in a loop after
calling node_creat (file_subs.c) to create /tmp/foo/bar:
1. At line 390 of file_subs.c there is a first attempt to create
/tmp/foo/bar which fails because /tmp/foo does not exist. This
happens in the function node_creat.
390 res = mkdir(nm, file_mode);
2. At line 463 chk_path is called in order to create the missing
/tmp/foo. It turns out the first argument of chk_path is
"/tmp/foo/bar/" (note the slash at the end) so chk_path creates
/tmp, /tmp/foo and /tmp/foo/bar instead of just /tmp and /tmp/foo.
463 if (nodirs || chk_path(nm,arcn->sb.st_uid,arcn->sb.st_gid)
< 0) {
464 syswarn(1, oerrno, "Could not create: %s", nm);
465 return(-1);
466 }
3. Now we're back at line 390: creating /tmp/foo/bar fails because
this time the directory already exists.
4. At line 457 /tmp/foo/bar is removed:
457 if ((ign = unlnk_exist(nm, arcn->type)) < 0)
458 return(-1);
5. And we're back at line 463 where chk_path creates /tmp/foo/bar
... it's looping ...
The first argument of chk_path seems to end with '/' because of the
cpio format. I could not reproduce the problem with the ustar
format. I did not look any further since I think it is chk_path
which is at fault here.
The diff below breaks out of the for loop when reaching the
terminating '/'. /tmp/foo/bar should be created by node_creat, not
by chk_path.
(please note this is a diff against -stable, not against -current)
Index: file_subs.c
===================================================================
RCS file: /cvs/src/bin/pax/file_subs.c,v
retrieving revision 1.47
diff -u -p -u -p -r1.47 file_subs.c
--- file_subs.c 19 Mar 2015 05:14:24 -0000 1.47
+++ file_subs.c 13 Feb 2016 21:55:34 -0000
@@ -611,7 +611,7 @@ chk_path(char *name, uid_t st_uid, gid_t
* work forward from the first / and check each part of the path
*/
spt = strchr(spt, '/');
- if (spt == NULL)
+ if (spt == NULL || (*spt == '/' && *(spt+1) == '\0'))
break;
*spt = '\0';
dmesg:
OpenBSD 5.8 (GENERIC.MP) #1236: Sun Aug 16 02:31:04 MDT 2015
dera...@amd64.openbsd.org:/usr/src/sys/arch/amd64/compile/GENERIC.MP
real mem = 2120941568 (2022MB)
avail mem = 2052829184 (1957MB)
mpath0 at root
scsibus0 at mpath0: 256 targets
mainbus0 at root
bios0 at mainbus0: SMBIOS rev. 2.6 @ 0xfc8b0 (23 entries)
bios0: vendor American Megatrends Inc. version "080015" date 05/03/2012
bios0: Standard XS35
acpi0 at bios0: rev 2
acpi0: sleep states S0 S3 S4 S5
acpi0: tables DSDT FACP APIC MCFG SLIC OEMB HPET GSCI
acpi0: wakeup devices P0P1(S4) AZAL(S3) P0P4(S4) P0P5(S4) JLAN(S3) P0P6(S4)
P0P7(S4) P0P8(S4) P0P9(S4) USB0(S3) USB1(S3) USB2(S3) USB3(S3) EUSB(S3)
acpitimer0 at acpi0: 3579545 Hz, 24 bits
acpimadt0 at acpi0 addr 0xfee00000: PC-AT compat
cpu0 at mainbus0: apid 0 (boot processor)
cpu0: Intel(R) Atom(TM) CPU D525 @ 1.80GHz, 1795.77 MHz
cpu0:
FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CFLUSH,DS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE,SSE3,DTES64,MWAIT,DS-CPL,TM2,SSSE3,CX16,xTPR,PDCM,MOVBE,NXE,LONG,LAHF,PERF,SENSOR
cpu0: 512KB 64b/line 8-way L2 cache
cpu0: smt 0, core 0, package 0
mtrr: Pentium Pro MTRR support, 8 var ranges, 88 fixed ranges
cpu0: apic clock running at 199MHz
cpu0: mwait min=64, max=64, C-substates=0.1, IBE
cpu1 at mainbus0: apid 2 (application processor)
cpu1: Intel(R) Atom(TM) CPU D525 @ 1.80GHz, 1797.40 MHz
cpu1:
FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CFLUSH,DS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE,SSE3,DTES64,MWAIT,DS-CPL,TM2,SSSE3,CX16,xTPR,PDCM,MOVBE,NXE,LONG,LAHF,PERF,SENSOR
cpu1: 512KB 64b/line 8-way L2 cache
cpu1: smt 0, core 1, package 0
cpu2 at mainbus0: apid 1 (application processor)
cpu2: Intel(R) Atom(TM) CPU D525 @ 1.80GHz, 1797.40 MHz
cpu2:
FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CFLUSH,DS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE,SSE3,DTES64,MWAIT,DS-CPL,TM2,SSSE3,CX16,xTPR,PDCM,MOVBE,NXE,LONG,LAHF,PERF,SENSOR
cpu2: 512KB 64b/line 8-way L2 cache
cpu2: smt 1, core 0, package 0
cpu3 at mainbus0: apid 3 (application processor)
cpu3: Intel(R) Atom(TM) CPU D525 @ 1.80GHz, 1797.40 MHz
cpu3:
FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CFLUSH,DS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE,SSE3,DTES64,MWAIT,DS-CPL,TM2,SSSE3,CX16,xTPR,PDCM,MOVBE,NXE,LONG,LAHF,PERF,SENSOR
cpu3: 512KB 64b/line 8-way L2 cache
cpu3: smt 1, core 1, package 0
ioapic0 at mainbus0: apid 4 pa 0xfec00000, version 20, 24 pins
ioapic0: misconfigured as apic 3, remapped to apid 4
acpimcfg0 at acpi0 addr 0xe0000000, bus 0-255
acpihpet0 at acpi0: 14318179 Hz
acpiprt0 at acpi0: bus 0 (PCI0)
acpiprt1 at acpi0: bus 4 (P0P1)
acpiprt2 at acpi0: bus 1 (P0P4)
acpiprt3 at acpi0: bus 2 (P0P5)
acpiprt4 at acpi0: bus -1 (P0P6)
acpiprt5 at acpi0: bus 3 (P0P7)
acpiprt6 at acpi0: bus -1 (P0P8)
acpiprt7 at acpi0: bus -1 (P0P9)
acpiec0 at acpi0
acpicpu0 at acpi0: C1(@1 halt!)
acpicpu1 at acpi0: C1(@1 halt!)
acpicpu2 at acpi0: C1(@1 halt!)
acpicpu3 at acpi0: C1(@1 halt!)
acpitz0 at acpi0: critical temperature is 104 degC
acpibtn0 at acpi0: SLPB
acpibtn1 at acpi0: PWRB
acpivideo0 at acpi0: GFX0
acpivout0 at acpivideo0: LCD_
pci0 at mainbus0 bus 0
0:31:2: mem address conflict 0xfc00/0x400
pchb0 at pci0 dev 0 function 0 "Intel Pineview DMI" rev 0x02
vga1 at pci0 dev 2 function 0 "Intel Pineview Video" rev 0x02
intagp0 at vga1
agp0 at intagp0: aperture at 0xd0000000, size 0x10000000
inteldrm0 at vga1
drm0 at inteldrm0
drm: fixme: max PWM is zero
inteldrm0: 1024x768
wsdisplay0 at vga1 mux 1: console (std, vt100 emulation)
wsdisplay0: screen 1-5 added (std, vt100 emulation)
"Intel Pineview Video" rev 0x02 at pci0 dev 2 function 1 not configured
azalia0 at pci0 dev 27 function 0 "Intel 82801GB HD Audio" rev 0x02: msi
azalia0: codecs: IDT 92HD81B1X
audio0 at azalia0
ppb0 at pci0 dev 28 function 0 "Intel 82801GB PCIE" rev 0x02: msi
pci1 at ppb0 bus 1
ppb1 at pci0 dev 28 function 1 "Intel 82801GB PCIE" rev 0x02: msi
pci2 at ppb1 bus 2
"JMicron SD/MMC" rev 0x80 at pci2 dev 0 function 0 not configured
sdhc0 at pci2 dev 0 function 2 "JMicron SD Host Controller" rev 0x80: apic 4
int 18
sdmmc0 at sdhc0
"JMicron Memory Stick" rev 0x80 at pci2 dev 0 function 3 not configured
jme0 at pci2 dev 0 function 5 "JMicron JMC250" rev 0x03: msi, address
80:ee:73:3d:3c:eb
jmphy0 at jme0 phy 1: JMP211 10/100/1000 PHY, rev. 1
ppb2 at pci0 dev 28 function 3 "Intel 82801GB PCIE" rev 0x02: msi
pci3 at ppb2 bus 3
rtwn0 at pci3 dev 0 function 0 "Realtek 8188CE" rev 0x01: msi
rtwn0: MAC/BB RTL8188CE, RF 6052 1T1R, address e0:91:53:73:58:ab
uhci0 at pci0 dev 29 function 0 "Intel 82801GB USB" rev 0x02: apic 4 int 23
uhci1 at pci0 dev 29 function 1 "Intel 82801GB USB" rev 0x02: apic 4 int 19
uhci2 at pci0 dev 29 function 2 "Intel 82801GB USB" rev 0x02: apic 4 int 18
uhci3 at pci0 dev 29 function 3 "Intel 82801GB USB" rev 0x02: apic 4 int 16
ehci0 at pci0 dev 29 function 7 "Intel 82801GB USB" rev 0x02: apic 4 int 23
usb0 at ehci0: USB revision 2.0
uhub0 at usb0 "Intel EHCI root hub" rev 2.00/1.00 addr 1
ppb3 at pci0 dev 30 function 0 "Intel 82801BAM Hub-to-PCI" rev 0xe2
pci4 at ppb3 bus 4
pcib0 at pci0 dev 31 function 0 "Intel NM10 LPC" rev 0x02
pciide0 at pci0 dev 31 function 2 "Intel 82801GB SATA" rev 0x02: DMA, channel 0
configured to native-PCI, channel 1 configured to native-PCI
pciide0: using apic 4 int 19 for native-PCI interrupt
wd0 at pciide0 channel 0 drive 0: <WDC WD1600BPVT-22JJ5T0>
wd0: 16-sector PIO, LBA48, 152627MB, 312581808 sectors
wd0(pciide0:0:0): using PIO mode 4, Ultra-DMA mode 6
ichiic0 at pci0 dev 31 function 3 "Intel 82801GB SMBus" rev 0x02: apic 4 int 19
iic0 at ichiic0
spdmem0 at iic0 addr 0x50: 2GB DDR3 SDRAM PC3-10600 SO-DIMM
usb1 at uhci0: USB revision 1.0
uhub1 at usb1 "Intel UHCI root hub" rev 1.00/1.00 addr 1
usb2 at uhci1: USB revision 1.0
uhub2 at usb2 "Intel UHCI root hub" rev 1.00/1.00 addr 1
usb3 at uhci2: USB revision 1.0
uhub3 at usb3 "Intel UHCI root hub" rev 1.00/1.00 addr 1
usb4 at uhci3: USB revision 1.0
uhub4 at usb4 "Intel UHCI root hub" rev 1.00/1.00 addr 1
isa0 at pcib0
isadma0 at isa0
pckbc0 at isa0 port 0x60/5 irq 1 irq 12
pckbd0 at pckbc0 (kbd slot)
wskbd0 at pckbd0: console keyboard, using wsdisplay0
pcppi0 at isa0 port 0x61
spkr0 at pcppi0
vscsi0 at root
scsibus1 at vscsi0: 256 targets
softraid0 at root
scsibus2 at softraid0: 256 targets
root on wd0a (17932b8d58a6d0f1.a) swap on wd0b dump on wd0b
usbdevs:
Controller /dev/usb0:
addr 1: high speed, self powered, config 1, EHCI root hub(0x0000),
Intel(0x8086), rev 1.00
port 1 powered
port 2 powered
port 3 powered
port 4 powered
port 5 powered
port 6 powered
port 7 powered
port 8 powered
Controller /dev/usb1:
addr 1: full speed, self powered, config 1, UHCI root hub(0x0000),
Intel(0x8086), rev 1.00
port 1 powered
port 2 powered
Controller /dev/usb2:
addr 1: full speed, self powered, config 1, UHCI root hub(0x0000),
Intel(0x8086), rev 1.00
port 1 powered
port 2 powered
Controller /dev/usb3:
addr 1: full speed, self powered, config 1, UHCI root hub(0x0000),
Intel(0x8086), rev 1.00
port 1 powered
port 2 powered
Controller /dev/usb4:
addr 1: full speed, self powered, config 1, UHCI root hub(0x0000),
Intel(0x8086), rev 1.00
port 1 powered
port 2 powered
