Hey Jeff, This patch fixes the oops, and the remote DFS link is readable. Great! Thanks! Robbert Op 6-12-2010 20:34, Jeff Layton schreef: > On Mon, 06 Dec 2010 20:12:34 +0100 > Robbert Kouprie <robbert@xxxxxx> wrote: > >> Hi Jeff, >> >> Op 6-12-2010 13:15, Jeff Layton schreef: >>> It's possible that cifs_mount will call cifs_build_path_to_root on a >>> newly instantiated cifs_sb. In that case, it's likely that the >>> master_tlink pointer has not yet been instantiated. >>> >>> Fix this by having cifs_build_path_to_root take a cifsTconInfo pointer >>> as well, and have the caller pass that in. >> >> I still get an oops on 2.6.37-rc4-git5 with the patch applied: >> >> BUG: unable to handle kernel NULL pointer dereference at 0000001c >> IP: [<f8fd533b>] cifs_sb_master_tcon+0x3/0x7 [cifs] >> *pde = 00000000 >> Oops: 0000 [#1] SMP >> last sysfs file: /sys/devices/virtual/bdi/cifs-2/uevent >> Modules linked in: hmac nls_utf8 cifs nls_base xfs exportfs loop >> snd_pcm parport_pc parport tpm_tis tpm tpm_bios snd_timer snd soundcore >> snd_page_alloc psmouse evdev pcspkr serio_raw i2c_piix4 i2c_core shpchp >> container pci_hotplug processor thermal_sys ac button ext3 jbd mbcache >> sd_mod crc_t10dif ide_cd_mod cdrom ata_generic ata_piix libata floppy >> e1000 mptspi mptscsih mptbase scsi_transport_spi scsi_mod piix ide_core >> [last unloaded: scsi_wait_scan] >> >> Pid: 1362, comm: ls Not tainted 2.6.37-rc4-git5 #2 440BX Desktop >> Reference Platform/VMware Virtual Platform >> EIP: 0060:[<f8fd533b>] EFLAGS: 00010286 CPU: 0 >> EIP is at cifs_sb_master_tcon+0x3/0x7 [cifs] >> EAX: 00000000 EBX: f7156800 ECX: 40000040 EDX: 00000002 >> ESI: f7156800 EDI: f7156a00 EBP: 00000000 ESP: f72fddb0 >> DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 >> Process ls (pid: 1362, ti=f72fc000 task=f71379e0 task.ti=f72fc000) >> Stack: >> f8fe14f3 002c80d0 00000000 f7156a00 f7156800 00000000 00000000 f8fcc96b >> 0000007f f7156838 f5073d80 f50ac840 f8ff9f30 f8fcc7fd f522b000 c10b8301 >> f50ac900 f5073d80 00000000 f50ac900 f50ac900 f72fded4 00000000 f8febc6f >> Call Trace: >> [<f8fe14f3>] ? cifs_root_iget+0x1e/0x13f [cifs] >> [<f8fcc96b>] ? cifs_do_mount+0x16e/0x247 [cifs] >> [<f8fcc7fd>] ? cifs_do_mount+0x0/0x247 [cifs] >> [<c10b8301>] ? vfs_kern_mount+0x9f/0x185 >> [<f8febc6f>] ? cifs_dfs_follow_mountpoint+0x233/0x3cc [cifs] >> [<c10bec73>] ? do_follow_link+0xb6/0x1b1 >> [<c10bf000>] ? link_path_walk+0x292/0x372 >> [<c10bf1a2>] ? path_walk+0x4f/0xae >> [<c10bf2d3>] ? do_path_lookup+0x1f/0x69 >> [<c10bfb70>] ? user_path_at+0x37/0x5f >> [<c1098af9>] ? vma_prio_tree_insert+0x17/0x2d >> [<c10b9981>] ? vfs_fstatat+0x2a/0x50 >> [<c10b99e8>] ? vfs_lstat+0x13/0x15 >> [<c10b99f9>] ? sys_lstat64+0xf/0x23 >> [<c1052a04>] ? sys_futex+0xfe/0x112 >> [<c10b500c>] ? filp_close+0x4e/0x54 >> [<c127f54f>] ? do_page_fault+0x0/0x36b >> [<c1002f9f>] ? sysenter_do_call+0x12/0x28 >> Code: c8 59 5f 39 ee 0f 8c 49 ff ff ff 8b 44 24 60 65 33 05 14 00 00 00 >> 74 05 e8 ef 9b 05 c8 83 c4 64 5b 5e 5f 5d c3 90 90 90 8b 40 08 <8b> 40 >> 1c c3 55 89 c5 83 3d a4 47 3b c1 00 57 89 d7 56 89 ce 53 >> EIP: [<f8fd533b>] cifs_sb_master_tcon+0x3/0x7 [cifs] SS:ESP 0068:f72fddb0 >> CR2: 000000000000001c >> ---[ end trace 61b6103d05293c43 ]--- >> >> Regards, >> Robbert >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-cifs" in >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> More majordomo info at http://vger.kernel.org/majordomo-info.html > > Interesting...does this (untested) patch fix it? It may have to be "wiggled" into > place depending on your tree. If so, I'm surprised no one has tripped > over this before... > > ----------------[snip]-------------------- > > cifs: fix check of error return from is_path_accessable > > This function will return 0 if everything went ok. > > Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx> > --- > fs/cifs/connect.c | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c > index bee397f..9fbe7c5 100644 > --- a/fs/cifs/connect.c > +++ b/fs/cifs/connect.c > @@ -2836,7 +2836,7 @@ remote_path_check: > goto mount_fail_check; > } > rc = is_path_accessible(xid, tcon, cifs_sb, full_path); > - if (rc != -EREMOTE) { > + if (rc != 0 && rc != -EREMOTE) { > kfree(full_path); > goto mount_fail_check; > } -- To unsubscribe from this list: send the line "unsubscribe linux-cifs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
