diff mbox series

linux-user: fix emulation of accept4/getpeername/getsockname/recvfrom syscalls

Message ID mvmmun7y7m0.fsf@suse.de
State New
Headers show
Series linux-user: fix emulation of accept4/getpeername/getsockname/recvfrom syscalls | expand

Commit Message

Andreas Schwab Feb. 7, 2019, 2:51 p.m. UTC 
System calls that return a socket address do so by writing the (possibly
truncated) address into the provided buffer space, but setting the addrlen
parameter to the actual size of the address.  To determine how much to
copy back to the target memory the emulation needs to remember the old
value of the addrlen parameter, so that it doesn't write past the buffer
limits.

Signed-off-by: Andreas Schwab <schwab@suse.de>
---
 linux-user/syscall.c | 38 ++++++++++++++++++++++----------------
 1 file changed, 22 insertions(+), 16 deletions(-)

Comments

no-reply@patchew.org Feb. 7, 2019, 3:22 p.m. UTC | #1 
Patchew URL: https://patchew.org/QEMU/mvmmun7y7m0.fsf@suse.de/



Hi,

This series seems to have some coding style problems. See output below for
more information:

Subject: [Qemu-devel] [PATCH] linux-user: fix emulation of accept4/getpeername/getsockname/recvfrom syscalls
Type: series
Message-id: mvmmun7y7m0.fsf@suse.de

=== TEST SCRIPT BEGIN ===
#!/bin/bash
git config --local diff.renamelimit 0
git config --local diff.renames True
git config --local diff.algorithm histogram
./scripts/checkpatch.pl --mailback base..
=== TEST SCRIPT END ===

Updating 3c8cf5a9c21ff8782164d1def7f44bd888713384
From https://github.com/patchew-project/qemu
   1dca054955..632351e0e1  master     -> master
 t [tag update]            patchew/20190207102445.71998-1-vsementsov@virtuozzo.com -> patchew/20190207102445.71998-1-vsementsov@virtuozzo.com
 * [new tag]               patchew/mvmmun7y7m0.fsf@suse.de -> patchew/mvmmun7y7m0.fsf@suse.de
Switched to a new branch 'test'
276d8b2c5d linux-user: fix emulation of accept4/getpeername/getsockname/recvfrom syscalls

=== OUTPUT BEGIN ===
ERROR: braces {} are necessary for all arms of this statement
#41: FILE: linux-user/syscall.c:2877:
+        if (put_user_u32(ret_addrlen, target_addrlen_addr))
[...]

ERROR: braces {} are necessary for all arms of this statement
#65: FILE: linux-user/syscall.c:2907:
+        if (put_user_u32(ret_addrlen, target_addrlen_addr))
[...]

ERROR: braces {} are necessary for all arms of this statement
#89: FILE: linux-user/syscall.c:2937:
+        if (put_user_u32(ret_addrlen, target_addrlen_addr))
[...]

total: 3 errors, 0 warnings, 98 lines checked

Commit 276d8b2c5d7b (linux-user: fix emulation of accept4/getpeername/getsockname/recvfrom syscalls) has style problems, please review.  If any of these errors
are false positives report them to the maintainer, see
CHECKPATCH in MAINTAINERS.
=== OUTPUT END ===

Test command exited with code: 1


The full log is available at
http://patchew.org/logs/mvmmun7y7m0.fsf@suse.de/testing.checkpatch/?type=message.
---
Email generated automatically by Patchew [http://patchew.org/].
Please send your feedback to patchew-devel@redhat.com
no-reply@patchew.org Feb. 7, 2019, 3:26 p.m. UTC | #2 
Patchew URL: https://patchew.org/QEMU/mvmmun7y7m0.fsf@suse.de/



Hi,

This series seems to have some coding style problems. See output below for
more information:

Subject: [Qemu-devel] [PATCH] linux-user: fix emulation of accept4/getpeername/getsockname/recvfrom syscalls
Message-id: mvmmun7y7m0.fsf@suse.de
Type: series

=== TEST SCRIPT BEGIN ===
#!/bin/bash
git config --local diff.renamelimit 0
git config --local diff.renames True
git config --local diff.algorithm histogram
./scripts/checkpatch.pl --mailback base..
=== TEST SCRIPT END ===

Updating 3c8cf5a9c21ff8782164d1def7f44bd888713384
From https://github.com/patchew-project/qemu
   1dca054..632351e  master     -> master
 - [tag update]      patchew/20190207102445.71998-1-vsementsov@virtuozzo.com -> patchew/20190207102445.71998-1-vsementsov@virtuozzo.com
 * [new tag]         patchew/mvmmun7y7m0.fsf@suse.de -> patchew/mvmmun7y7m0.fsf@suse.de
Submodule 'capstone' (https://git.qemu.org/git/capstone.git) registered for path 'capstone'
Submodule 'dtc' (https://git.qemu.org/git/dtc.git) registered for path 'dtc'
Submodule 'roms/QemuMacDrivers' (https://git.qemu.org/git/QemuMacDrivers.git) registered for path 'roms/QemuMacDrivers'
Submodule 'roms/SLOF' (https://git.qemu.org/git/SLOF.git) registered for path 'roms/SLOF'
Submodule 'roms/ipxe' (https://git.qemu.org/git/ipxe.git) registered for path 'roms/ipxe'
Submodule 'roms/openbios' (https://git.qemu.org/git/openbios.git) registered for path 'roms/openbios'
Submodule 'roms/openhackware' (https://git.qemu.org/git/openhackware.git) registered for path 'roms/openhackware'
Submodule 'roms/qemu-palcode' (https://git.qemu.org/git/qemu-palcode.git) registered for path 'roms/qemu-palcode'
Submodule 'roms/seabios' (https://git.qemu.org/git/seabios.git/) registered for path 'roms/seabios'
Submodule 'roms/seabios-hppa' (https://github.com/hdeller/seabios-hppa.git) registered for path 'roms/seabios-hppa'
Submodule 'roms/sgabios' (https://git.qemu.org/git/sgabios.git) registered for path 'roms/sgabios'
Submodule 'roms/skiboot' (https://git.qemu.org/git/skiboot.git) registered for path 'roms/skiboot'
Submodule 'roms/u-boot' (https://git.qemu.org/git/u-boot.git) registered for path 'roms/u-boot'
Submodule 'roms/u-boot-sam460ex' (https://git.qemu.org/git/u-boot-sam460ex.git) registered for path 'roms/u-boot-sam460ex'
Submodule 'tests/fp/berkeley-softfloat-3' (https://github.com/cota/berkeley-softfloat-3) registered for path 'tests/fp/berkeley-softfloat-3'
Submodule 'tests/fp/berkeley-testfloat-3' (https://github.com/cota/berkeley-testfloat-3) registered for path 'tests/fp/berkeley-testfloat-3'
Submodule 'ui/keycodemapdb' (https://git.qemu.org/git/keycodemapdb.git) registered for path 'ui/keycodemapdb'
Cloning into 'capstone'...
Submodule path 'capstone': checked out '22ead3e0bfdb87516656453336160e0a37b066bf'
Cloning into 'dtc'...
Submodule path 'dtc': checked out '88f18909db731a627456f26d779445f84e449536'
Cloning into 'roms/QemuMacDrivers'...
Submodule path 'roms/QemuMacDrivers': checked out '90c488d5f4a407342247b9ea869df1c2d9c8e266'
Cloning into 'roms/SLOF'...
Submodule path 'roms/SLOF': checked out 'a5b428e1c1eae703bdd62a3f527223c291ee3fdc'
Cloning into 'roms/ipxe'...
Submodule path 'roms/ipxe': checked out 'de4565cbe76ea9f7913a01f331be3ee901bb6e17'
Cloning into 'roms/openbios'...
Submodule path 'roms/openbios': checked out '441a84d3a642a10b948369c63f32367e8ff6395b'
Cloning into 'roms/openhackware'...
Submodule path 'roms/openhackware': checked out 'c559da7c8eec5e45ef1f67978827af6f0b9546f5'
Cloning into 'roms/qemu-palcode'...
Submodule path 'roms/qemu-palcode': checked out '51c237d7e20d05100eacadee2f61abc17e6bc097'
Cloning into 'roms/seabios'...
Submodule path 'roms/seabios': checked out 'a698c8995ffb2838296ec284fe3c4ad33dfca307'
Cloning into 'roms/seabios-hppa'...
Submodule path 'roms/seabios-hppa': checked out '1ef99a01572c2581c30e16e6fe69e9ea2ef92ce0'
Cloning into 'roms/sgabios'...
Submodule path 'roms/sgabios': checked out 'cbaee52287e5f32373181cff50a00b6c4ac9015a'
Cloning into 'roms/skiboot'...
Submodule path 'roms/skiboot': checked out 'e0ee24c27a172bcf482f6f2bc905e6211c134bcc'
Cloning into 'roms/u-boot'...
Submodule path 'roms/u-boot': checked out 'd85ca029f257b53a96da6c2fb421e78a003a9943'
Cloning into 'roms/u-boot-sam460ex'...
Submodule path 'roms/u-boot-sam460ex': checked out '60b3916f33e617a815973c5a6df77055b2e3a588'
Cloning into 'tests/fp/berkeley-softfloat-3'...
Submodule path 'tests/fp/berkeley-softfloat-3': checked out 'b64af41c3276f97f0e181920400ee056b9c88037'
Cloning into 'tests/fp/berkeley-testfloat-3'...
Submodule path 'tests/fp/berkeley-testfloat-3': checked out '5a59dcec19327396a011a17fd924aed4fec416b3'
Cloning into 'ui/keycodemapdb'...
Submodule path 'ui/keycodemapdb': checked out '6b3d716e2b6472eb7189d3220552280ef3d832ce'
Switched to a new branch 'test'
276d8b2 linux-user: fix emulation of accept4/getpeername/getsockname/recvfrom syscalls

=== OUTPUT BEGIN ===
ERROR: braces {} are necessary for all arms of this statement
#41: FILE: linux-user/syscall.c:2877:
+        if (put_user_u32(ret_addrlen, target_addrlen_addr))
[...]

ERROR: braces {} are necessary for all arms of this statement
#65: FILE: linux-user/syscall.c:2907:
+        if (put_user_u32(ret_addrlen, target_addrlen_addr))
[...]

ERROR: braces {} are necessary for all arms of this statement
#89: FILE: linux-user/syscall.c:2937:
+        if (put_user_u32(ret_addrlen, target_addrlen_addr))
[...]

total: 3 errors, 0 warnings, 98 lines checked

Commit 276d8b2c5d7b (linux-user: fix emulation of accept4/getpeername/getsockname/recvfrom syscalls) has style problems, please review.  If any of these errors
are false positives report them to the maintainer, see
CHECKPATCH in MAINTAINERS.
=== OUTPUT END ===

Test command exited with code: 1


The full log is available at
http://patchew.org/logs/mvmmun7y7m0.fsf@suse.de/testing.checkpatch/?type=message.
---
Email generated automatically by Patchew [http://patchew.org/].
Please send your feedback to patchew-devel@redhat.com
Laurent Vivier Feb. 14, 2019, 9:17 a.m. UTC | #3 
On 07/02/2019 15:51, Andreas Schwab wrote:
> System calls that return a socket address do so by writing the (possibly
> truncated) address into the provided buffer space, but setting the addrlen
> parameter to the actual size of the address.  To determine how much to
> copy back to the target memory the emulation needs to remember the old
> value of the addrlen parameter, so that it doesn't write past the buffer
> limits.
> 
> Signed-off-by: Andreas Schwab <schwab@suse.de>

Andreas,

could you fix the coding style errors reported by patchew?

Thanks,
Laurent

> ---
>  linux-user/syscall.c | 38 ++++++++++++++++++++++----------------
>  1 file changed, 22 insertions(+), 16 deletions(-)
> 
> diff --git a/linux-user/syscall.c b/linux-user/syscall.c
> index 55fa235a56..90bfda3563 100644
> --- a/linux-user/syscall.c
> +++ b/linux-user/syscall.c
> @@ -2884,7 +2884,7 @@ static abi_long do_sendrecvmmsg(int fd, abi_ulong target_msgvec,
>  static abi_long do_accept4(int fd, abi_ulong target_addr,
>                             abi_ulong target_addrlen_addr, int flags)
>  {
> -    socklen_t addrlen;
> +    socklen_t addrlen, ret_addrlen;
>      void *addr;
>      abi_long ret;
>      int host_flags;
> @@ -2908,10 +2908,11 @@ static abi_long do_accept4(int fd, abi_ulong target_addr,
>  
>      addr = alloca(addrlen);
>  
> -    ret = get_errno(safe_accept4(fd, addr, &addrlen, host_flags));
> +    ret_addrlen = addrlen;
> +    ret = get_errno(safe_accept4(fd, addr, &ret_addrlen, host_flags));
>      if (!is_error(ret)) {
> -        host_to_target_sockaddr(target_addr, addr, addrlen);
> -        if (put_user_u32(addrlen, target_addrlen_addr))
> +        host_to_target_sockaddr(target_addr, addr, MIN(addrlen, ret_addrlen));
> +        if (put_user_u32(ret_addrlen, target_addrlen_addr))
>              ret = -TARGET_EFAULT;
>      }
>      return ret;
> @@ -2921,7 +2922,7 @@ static abi_long do_accept4(int fd, abi_ulong target_addr,
>  static abi_long do_getpeername(int fd, abi_ulong target_addr,
>                                 abi_ulong target_addrlen_addr)
>  {
> -    socklen_t addrlen;
> +    socklen_t addrlen, ret_addrlen;
>      void *addr;
>      abi_long ret;
>  
> @@ -2937,10 +2938,11 @@ static abi_long do_getpeername(int fd, abi_ulong target_addr,
>  
>      addr = alloca(addrlen);
>  
> -    ret = get_errno(getpeername(fd, addr, &addrlen));
> +    ret_addrlen = addrlen;
> +    ret = get_errno(getpeername(fd, addr, &ret_addrlen));
>      if (!is_error(ret)) {
> -        host_to_target_sockaddr(target_addr, addr, addrlen);
> -        if (put_user_u32(addrlen, target_addrlen_addr))
> +        host_to_target_sockaddr(target_addr, addr, MIN(addrlen, ret_addrlen));
> +        if (put_user_u32(ret_addrlen, target_addrlen_addr))
>              ret = -TARGET_EFAULT;
>      }
>      return ret;
> @@ -2950,7 +2952,7 @@ static abi_long do_getpeername(int fd, abi_ulong target_addr,
>  static abi_long do_getsockname(int fd, abi_ulong target_addr,
>                                 abi_ulong target_addrlen_addr)
>  {
> -    socklen_t addrlen;
> +    socklen_t addrlen, ret_addrlen;
>      void *addr;
>      abi_long ret;
>  
> @@ -2966,10 +2968,11 @@ static abi_long do_getsockname(int fd, abi_ulong target_addr,
>  
>      addr = alloca(addrlen);
>  
> -    ret = get_errno(getsockname(fd, addr, &addrlen));
> +    ret_addrlen = addrlen;
> +    ret = get_errno(getsockname(fd, addr, &ret_addrlen));
>      if (!is_error(ret)) {
> -        host_to_target_sockaddr(target_addr, addr, addrlen);
> -        if (put_user_u32(addrlen, target_addrlen_addr))
> +        host_to_target_sockaddr(target_addr, addr, MIN(addrlen, ret_addrlen));
> +        if (put_user_u32(ret_addrlen, target_addrlen_addr))
>              ret = -TARGET_EFAULT;
>      }
>      return ret;
> @@ -3042,7 +3045,7 @@ static abi_long do_recvfrom(int fd, abi_ulong msg, size_t len, int flags,
>                              abi_ulong target_addr,
>                              abi_ulong target_addrlen)
>  {
> -    socklen_t addrlen;
> +    socklen_t addrlen, ret_addrlen;
>      void *addr;
>      void *host_msg;
>      abi_long ret;
> @@ -3060,10 +3063,12 @@ static abi_long do_recvfrom(int fd, abi_ulong msg, size_t len, int flags,
>              goto fail;
>          }
>          addr = alloca(addrlen);
> +        ret_addrlen = addrlen;
>          ret = get_errno(safe_recvfrom(fd, host_msg, len, flags,
> -                                      addr, &addrlen));
> +                                      addr, &ret_addrlen));
>      } else {
>          addr = NULL; /* To keep compiler quiet.  */
> +        addrlen = 0; /* To keep compiler quiet.  */
>          ret = get_errno(safe_recvfrom(fd, host_msg, len, flags, NULL, 0));
>      }
>      if (!is_error(ret)) {
> @@ -3076,8 +3081,9 @@ static abi_long do_recvfrom(int fd, abi_ulong msg, size_t len, int flags,
>              }
>          }
>          if (target_addr) {
> -            host_to_target_sockaddr(target_addr, addr, addrlen);
> -            if (put_user_u32(addrlen, target_addrlen)) {
> +            host_to_target_sockaddr(target_addr, addr,
> +                                    MIN(addrlen, ret_addrlen));
> +            if (put_user_u32(ret_addrlen, target_addrlen)) {
>                  ret = -TARGET_EFAULT;
>                  goto fail;
>              }
>
Laurent Vivier Feb. 14, 2019, 1:25 p.m. UTC | #4 
On 07/02/2019 15:51, Andreas Schwab wrote:
> System calls that return a socket address do so by writing the (possibly
> truncated) address into the provided buffer space, but setting the addrlen
> parameter to the actual size of the address.  To determine how much to
> copy back to the target memory the emulation needs to remember the old
> value of the addrlen parameter, so that it doesn't write past the buffer
> limits.
> 
> Signed-off-by: Andreas Schwab <schwab@suse.de>
> ---
>  linux-user/syscall.c | 38 ++++++++++++++++++++++----------------
>  1 file changed, 22 insertions(+), 16 deletions(-)

Reviewed-by: Laurent Vivier <laurent@vivier.eu>
diff mbox series

Patch

diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 55fa235a56..90bfda3563 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -2884,7 +2884,7 @@  static abi_long do_sendrecvmmsg(int fd, abi_ulong target_msgvec,
 static abi_long do_accept4(int fd, abi_ulong target_addr,
                            abi_ulong target_addrlen_addr, int flags)
 {
-    socklen_t addrlen;
+    socklen_t addrlen, ret_addrlen;
     void *addr;
     abi_long ret;
     int host_flags;
@@ -2908,10 +2908,11 @@  static abi_long do_accept4(int fd, abi_ulong target_addr,
 
     addr = alloca(addrlen);
 
-    ret = get_errno(safe_accept4(fd, addr, &addrlen, host_flags));
+    ret_addrlen = addrlen;
+    ret = get_errno(safe_accept4(fd, addr, &ret_addrlen, host_flags));
     if (!is_error(ret)) {
-        host_to_target_sockaddr(target_addr, addr, addrlen);
-        if (put_user_u32(addrlen, target_addrlen_addr))
+        host_to_target_sockaddr(target_addr, addr, MIN(addrlen, ret_addrlen));
+        if (put_user_u32(ret_addrlen, target_addrlen_addr))
             ret = -TARGET_EFAULT;
     }
     return ret;
@@ -2921,7 +2922,7 @@  static abi_long do_accept4(int fd, abi_ulong target_addr,
 static abi_long do_getpeername(int fd, abi_ulong target_addr,
                                abi_ulong target_addrlen_addr)
 {
-    socklen_t addrlen;
+    socklen_t addrlen, ret_addrlen;
     void *addr;
     abi_long ret;
 
@@ -2937,10 +2938,11 @@  static abi_long do_getpeername(int fd, abi_ulong target_addr,
 
     addr = alloca(addrlen);
 
-    ret = get_errno(getpeername(fd, addr, &addrlen));
+    ret_addrlen = addrlen;
+    ret = get_errno(getpeername(fd, addr, &ret_addrlen));
     if (!is_error(ret)) {
-        host_to_target_sockaddr(target_addr, addr, addrlen);
-        if (put_user_u32(addrlen, target_addrlen_addr))
+        host_to_target_sockaddr(target_addr, addr, MIN(addrlen, ret_addrlen));
+        if (put_user_u32(ret_addrlen, target_addrlen_addr))
             ret = -TARGET_EFAULT;
     }
     return ret;
@@ -2950,7 +2952,7 @@  static abi_long do_getpeername(int fd, abi_ulong target_addr,
 static abi_long do_getsockname(int fd, abi_ulong target_addr,
                                abi_ulong target_addrlen_addr)
 {
-    socklen_t addrlen;
+    socklen_t addrlen, ret_addrlen;
     void *addr;
     abi_long ret;
 
@@ -2966,10 +2968,11 @@  static abi_long do_getsockname(int fd, abi_ulong target_addr,
 
     addr = alloca(addrlen);
 
-    ret = get_errno(getsockname(fd, addr, &addrlen));
+    ret_addrlen = addrlen;
+    ret = get_errno(getsockname(fd, addr, &ret_addrlen));
     if (!is_error(ret)) {
-        host_to_target_sockaddr(target_addr, addr, addrlen);
-        if (put_user_u32(addrlen, target_addrlen_addr))
+        host_to_target_sockaddr(target_addr, addr, MIN(addrlen, ret_addrlen));
+        if (put_user_u32(ret_addrlen, target_addrlen_addr))
             ret = -TARGET_EFAULT;
     }
     return ret;
@@ -3042,7 +3045,7 @@  static abi_long do_recvfrom(int fd, abi_ulong msg, size_t len, int flags,
                             abi_ulong target_addr,
                             abi_ulong target_addrlen)
 {
-    socklen_t addrlen;
+    socklen_t addrlen, ret_addrlen;
     void *addr;
     void *host_msg;
     abi_long ret;
@@ -3060,10 +3063,12 @@  static abi_long do_recvfrom(int fd, abi_ulong msg, size_t len, int flags,
             goto fail;
         }
         addr = alloca(addrlen);
+        ret_addrlen = addrlen;
         ret = get_errno(safe_recvfrom(fd, host_msg, len, flags,
-                                      addr, &addrlen));
+                                      addr, &ret_addrlen));
     } else {
         addr = NULL; /* To keep compiler quiet.  */
+        addrlen = 0; /* To keep compiler quiet.  */
         ret = get_errno(safe_recvfrom(fd, host_msg, len, flags, NULL, 0));
     }
     if (!is_error(ret)) {
@@ -3076,8 +3081,9 @@  static abi_long do_recvfrom(int fd, abi_ulong msg, size_t len, int flags,
             }
         }
         if (target_addr) {
-            host_to_target_sockaddr(target_addr, addr, addrlen);
-            if (put_user_u32(addrlen, target_addrlen)) {
+            host_to_target_sockaddr(target_addr, addr,
+                                    MIN(addrlen, ret_addrlen));
+            if (put_user_u32(ret_addrlen, target_addrlen)) {
                 ret = -TARGET_EFAULT;
                 goto fail;
             }